Staff directory Kostas Kostarelos

Kostas Kostarelos

ICREA Professor & Severo Ochoa Distinguished Professor
kostas.kostarelos(ELIMINAR)@icn2.cat
Nanomedicine

ORCID: 0000-0002-2224-6672

Publications

2024

Clinical translation of graphene-based medical technology
Kostas Kostarelos; Carolina Aguilar; José A. Garrido Nature Reviews Electrical Engineering; 1 (2): 75 - 76. 2024. 10.1038/s44287-024-00020-1.
First-in-human controlled inhalation of thin graphene oxide nanosheets to study acute cardiorespiratory responses
Andrews, Jack P M; Joshi, Shruti S; Tzolos, Evangelos; Syed, Maaz B; Cuthbert, Hayley; Crica, Livia E; Lozano, Neus; Okwelogu, Emmanuel; Raftis, Jennifer B; Bruce, Lorraine; Poland, Craig A; Duffin, Rodger; Fokkens, Paul H B; Boere, A John F; Leseman, Daan L A C; Megson, Ian L; Whitfield, Phil D; Ziegler, Kerstin; Tammireddy, Seshu; Hadjidemetriou, Marilena; Bussy, Cyrill; Cassee, Flemming R; Newby, David E; Kostarelos, Kostas; Miller, Mark R Nature Nanotechnology; 19 (3): 271 - 272. 2024. 10.1038/s41565-023-01572-3.
Graphene oxide activates canonical TGFβ signalling in a human chondrocyte cell line via increased plasma membrane tension
Ogene, Leona; Woods, Steven; Hetmanski, Joseph; Lozano, Neus; Karakasidi, Angeliki; Caswell, Patrick T; Kostarelos, Kostas; Domingos, Marco A N; Vranic, Sandra; Kimber, Susan J Nanoscale; 16 (11): 5653 - 5664. 2024. 10.1039/d3nr06033k.
In vivo biomolecule corona and the transformation of a foe into an ally for nanomedicine
Hadjidemetriou, Marilena; Mahmoudi, Morteza; Kostarelos, Kostas Nature Reviews Materials; 9 (4): 219 - 222. 2024. 10.1038/s41578-024-00658-1.
Nanoporous graphene-based thin-film microelectrodes for in vivo high-resolution neural recording and stimulation
Viana, Damia; Walston, Steven T; Masvidal-Codina, Eduard; Illa, Xavi; Rodriguez-Meana, Bruno; del Valle, Jaume; Hayward, Andrew; Dodd, Abbie; Loret, Thomas; Prats-Alfonso, Elisabet; de la Oliva, Natalia; Palma, Marie; del Corro, Elena; Bernicola, Maria del Pilar; Rodriguez-Lucas, Elisa; Gener, Thomas; de la Cruz, Jose Manuel; Torres-Miranda, Miguel; Duvan, Fikret Taygun; Ria, Nicola; Sperling, Justin; Marti-Sanchez, Sara; Spadaro, Maria Chiara; Hebert, Clement; Savage, Sinead; Arbiol, Jordi; Guimera-Brunet, Anton; Puig, M Victoria; Yvert, Blaise; Navarro, Xavier; Kostarelos, Kostas; Garrido, Jose A Nature Nanotechnology; 2024. 10.1038/s41565-023-01570-5.

2023

Correlative radioimaging and mass spectrometry imaging: a powerful combination to study C-14-graphene oxide in vivo biodistribution
Cazier, H; Malgorn, C; Georgin, D; Fresneau, N; Beau, F; Kostarelos, K; Bussy, C; Campidelli, S; Pinault, M; Mayne-L'Hermite, M; Taran, F; Junot, C; Fenaille, F; Sallustrau, A; Colsch, B Nanoscale; 15 (11): 5510 - 5518. 2023. 10.1039/d2nr06753f. IF: 6.700
Defect-free graphene enhances enzyme delivery to fibroblasts derived from patients with lysosomal storage disorders
Chen, YX; Taufiq, T; Zeng, NT; Lozano, N; Karakasidi, A; Church, H; Jovanovic, A; Jones, SA; Panigrahi, A; Larrosa, I; Kostarelos, K; Casiraghi, C; Vranic, S Nanoscale; 15 (21): 9348 - 9364. 2023. 10.1039/d2nr04971f. IF: 6.700
Delivery of graphene oxide nanosheets modulates glutamate release and normalizes amygdala synaptic plasticity to improve anxiety-related behavior
Pati, E; Biagioni, AF; Casani, R; Lozano, N; Kostarelos, K; Cellot, G; Ballerini, L Nanoscale; 15 (46): 18581 - 18591. 2023. 10.1039/d3nr04490d. IF: 6.700
Graphene oxide elicits microbiome-dependent type 2 immune responses via the aryl hydrocarbon receptor
Peng, GT; Sinkko, HM; Alenius, H; Lozano, N; Kostarelos, K; Bräutigam, L; Fadeel, B Nature Nanotechnology; 18 (1): 42 - +. 2023. 10.1038/s41565-022-01260-8. IF: 38.300
Graphene Oxide Nanoscale Platform Enhances the Anti-Cancer Properties of Bortezomib in Glioblastoma Models
Sharp, PS; Stylianou, M; Arellano, LM; Neves, JC; Gravagnuolo, AM; Dodd, A; Barr, K; Lozano, N; Kisby, T; Kostarelos, K Advanced Healthcare Materials; 12 (3): e2201968. 2023. 10.1002/adhm.202201968. IF: 10.000
Graphene Oxide Nanosheets Hamper Glutamate Mediated Excitotoxicity and Protect Neuronal Survival In An In vitro Stroke Model
Tortella, L; Santini, I; Lozano, N; Kostarelos, K; Cellot, G; Ballerini, L Chemistry-A European Journal; 29 (67): e202301762. 2023. 10.1002/chem.202301762. IF: 4.300
Graphene Oxide Nanosheets Reduce Astrocyte Reactivity to Inflammation and Ameliorate Experimental Autoimmune Encephalomyelitis
Di Mauro, G; Amoriello, R; Lozano, N; Carnasciali, A; Guasti, D; Becucci, M; Cellot, G; Kostarelos, K; Ballerini, C; Ballerini, L Acs Nano; 17 (3): 1965 - 1978. 2023. 10.1021/acsnano.2c06609. IF: 17.100
Human lung organoids predict response to carbon-based nanomaterials and model pulmonary fibrosis
Issa, R; Lozano, N; Kostarelos, K; Vranic, S Tissue Engineering Part a; 29 (13-14) 2023. . IF: 4.100
Lung Persistence, Biodegradation, and Elimination of Graphene-Based Materials are Predominantly Size-Dependent and Mediated by Alveolar Phagocytes
Loret, T; de Luna, LAV; Lucherelli, MA; Fordham, A; Lozano, N; Bianco, A; Kostarelos, K; Bussy, C Small; 19 (39): e2301201. 2023. 10.1002/smll.202301201. IF: 13.300
Pulmonary Toxicity of Boron Nitride Nanomaterials Is Aspect Ratio Dependent
de Luna, LAV; Loret, T; He, YL; Legnani, M; Lin, HZ; Galibert, AM; Fordham, A; Holme, S; Castillo, AED; Bonaccorso, F; Bianco, A; Flahaut, E; Kostarelos, K; Bussy, C Acs Nano; 17 (24): 24919 - 24935. 2023. 10.1021/acsnano.3c06599. IF: 17.100

2022

Author Correction: Reasons for success and lessons learnt from nanoscale vaccines against COVID-19
Kisby T; Yilmazer A; Kostarelos K Nature Nanotechnology; 17 (6): 671 - 671. 2022. 10.1038/s41565-022-01141-0. IF: 40.523
Converging Mechanisms of Epileptogenesis and Their Insight in Glioblastoma
Hills K.E., Kostarelos K., Wykes R.C. Frontiers in Molecular Neuroscience; 15 (903115) 2022. 10.3389/fnmol.2022.903115.

Glioblastoma (GBM) is the most common and advanced form of primary malignant tumor occurring in the adult central nervous system, and it is frequently associated with epilepsy, a debilitating comorbidity. Seizures are observed both pre- and post-surgical resection, indicating that several pathophysiological mechanisms are shared but also prompting questions about how the process of epileptogenesis evolves throughout GBM progression. Molecular mutations commonly seen in primary GBM, i.e., in PTEN and p53, and their associated downstream effects are known to influence seizure likelihood. Similarly, various intratumoral mechanisms, such as GBM-induced blood-brain barrier breakdown and glioma-immune cell interactions within the tumor microenvironment are also cited as contributing to network hyperexcitability. Substantial alterations to peri-tumoral glutamate and chloride transporter expressions, as well as widespread dysregulation of GABAergic signaling are known to confer increased epileptogenicity and excitotoxicity. The abnormal characteristics of GBM alter neuronal network function to result in metabolically vulnerable and hyperexcitable peri-tumoral tissue, properties the tumor then exploits to favor its own growth even post-resection. It is evident that there is a complex, dynamic interplay between GBM and epilepsy that promotes the progression of both pathologies. This interaction is only more complicated by the concomitant presence of spreading depolarization (SD). The spontaneous, high-frequency nature of GBM-associated epileptiform activity and SD-associated direct current (DC) shifts require technologies capable of recording brain signals over a wide bandwidth, presenting major challenges for comprehensive electrophysiological investigations. This review will initially provide a detailed examination of the underlying mechanisms that promote network hyperexcitability in GBM. We will then discuss how an investigation of these pathologies from a network level, and utilization of novel electrophysiological tools, will yield a more-effective, clinically-relevant understanding of GBM-related epileptogenesis. Further to this, we will evaluate the clinical relevance of current preclinical research and consider how future therapeutic advancements may impact the bidirectional relationship between GBM, SDs, and seizures. Copyright © 2022 Hills, Kostarelos and Wykes.

View abstract
Effects of Lateral Size, Thickness, and Stabilizer Concentration on the Cytotoxicity of Defect-Free Graphene Nanosheets: Implications for Biological Applications
Hu C.-X., Read O., Shin Y., Chen Y., Wang J., Boyes M., Zeng N., Panigrahi A., Kostarelos K., Larrosa I., Vranic S., Casiraghi C. ACS Applied Nano Materials; 5 (9): 12626 - 12636. 2022. 10.1021/acsanm.2c02403.

In this work, we apply liquid cascade centrifugation to highly concentrated graphene dispersions produced by liquid-phase exfoliation in water with an insoluble bis-pyrene stabilizer to obtain fractions containing nanosheets with different lateral size distributions. The concentration, stability, size, thickness, and the cytotoxicity profile are studied as a function of the initial stabilizer concentration for each fraction. Our results show that there is a critical initial amount of stabilizer (0.4 mg/mL) above which the dispersions show reduced concentration, stability, and biocompatibility, no matter the lateral size of the flakes. © 2022 The Authors. Published by American Chemical Society.

View abstract
Full-bandwidth electrophysiology of seizures and epileptiform activity enabled by flexible graphene microtransistor depth neural probes
Bonaccini Calia A., Masvidal-Codina E., Smith T.M., Schäfer N., Rathore D., Rodríguez-Lucas E., Illa X., De la Cruz J.M., Del Corro E., Prats-Alfonso E., Viana D., Bousquet J., Hébert C., Martínez-Aguilar J., Sperling J.R., Drummond M., Halder A., Dodd A., Barr K., Savage S., Fornell J., Sort J., Guger C., Villa R., Kostarelos K., Wykes R.C., Guimerà-Brunet A., Garrido J.A. Nature Nanotechnology; 17 (3): 301 - 309. 2022. 10.1038/s41565-021-01041-9. IF: 39.213

Mapping the entire frequency bandwidth of brain electrophysiological signals is of paramount importance for understanding physiological and pathological states. The ability to record simultaneously DC-shifts, infraslow oscillations (<0.1 Hz), typical local field potentials (0.1–80 Hz) and higher frequencies (80–600 Hz) using the same recording site would particularly benefit preclinical epilepsy research and could provide clinical biomarkers for improved seizure onset zone delineation. However, commonly used metal microelectrode technology suffers from instabilities that hamper the high fidelity of DC-coupled recordings, which are needed to access signals of very low frequency. In this study we used flexible graphene depth neural probes (gDNPs), consisting of a linear array of graphene microtransistors, to concurrently record DC-shifts and high-frequency neuronal activity in awake rodents. We show here that gDNPs can reliably record and map with high spatial resolution seizures, pre-ictal DC-shifts and seizure-associated spreading depolarizations together with higher frequencies through the cortical laminae to the hippocampus in a mouse model of chemically induced seizures. Moreover, we demonstrate the functionality of chronically implanted devices over 10 weeks by recording with high fidelity spontaneous spike-wave discharges and associated infraslow oscillations in a rat model of absence epilepsy. Altogether, our work highlights the suitability of this technology for in vivo electrophysiology research, and in particular epilepsy research, by allowing stable and chronic DC-coupled recordings. © 2021, The Author(s), under exclusive licence to Springer Nature Limited.

View abstract
Graphene oxide modulates dendritic cell ability to promote T cell activation and cytokine production
Parker, H; Gravagnuolo, AM; Vranic, S; Crica, LE; Newman, L; Carnell, O; Bussy, C; Dookie, RS; Prestat, E; Haigh, SJ; Lozano, N; Kostarelos, K; MacDonald, AS Nanoscale; 14 (46): 17297 - 17314. 2022. 10.1039/d2nr02169b. IF: 8.307
Hazard assessment of abraded thermoplastic composites reinforced with reduced graphene oxide
Chortarea S., Kuru O.C., Netkueakul W., Pelin M., Keshavan S., Song Z., Ma B., Gómes J., Abalos E.V., Luna L.A.V.D., Loret T., Fordham A., Drummond M., Kontis N., Anagnostopoulos G., Paterakis G., Cataldi P., Tubaro A., Galiotis C., Kinloch I., Fadeel B., Bussy C., Kostarelos K., Buerki-Thurnherr T., Prato M., Bianco A., Wick P. Journal of Hazardous Materials; 435 (129053) 2022. 10.1016/j.jhazmat.2022.129053.

Graphene-related materials (GRMs) are subject to intensive investigations and considerable progress has been made in recent years in terms of safety assessment. However, limited information is available concerning the hazard potential of GRM-containing products such as graphene-reinforced composites. In the present study, we conducted a comprehensive investigation of the potential biological effects of particles released through an abrasion process from reduced graphene oxide (rGO)-reinforced composites of polyamide 6 (PA6), a widely used engineered thermoplastic polymer, in comparison to as-produced rGO. First, a panel of well-established in vitro models, representative of the immune system and possible target organs such as the lungs, the gut, and the skin, was applied. Limited responses to PA6-rGO exposure were found in the different in vitro models. Only as-produced rGO induced substantial adverse effects, in particular in macrophages. Since inhalation of airborne materials is a key occupational concern, we then sought to test whether the in vitro responses noted for these materials would translate into adverse effects in vivo. To this end, the response at 1, 7 and 28 days after a single pulmonary exposure was evaluated in mice. In agreement with the in vitro data, PA6-rGO induced a modest and transient pulmonary inflammation, resolved by day 28. In contrast, rGO induced a longer-lasting, albeit moderate inflammation that did not lead to tissue remodeling within 28 days. Taken together, the present study suggests a negligible impact on human health under acute exposure conditions of GRM fillers such as rGO when released from composites at doses expected at the workplace. © 2022 The Authors

View abstract
Innate but Not Adaptive Immunity Regulates Lung Recovery from Chronic Exposure to Graphene Oxide Nanosheets
Loret T., de Luna L.A.V., Fordham A., Arshad A., Barr K., Lozano N., Kostarelos K., Bussy C. Advanced Science; 9 (11, 2104559) 2022. 10.1002/advs.202104559. IF: 16.806

Graphene has drawn a lot of interest in the material community due to unique physicochemical properties. Owing to a high surface area to volume ratio and free oxygen groups, the oxidized derivative, graphene oxide (GO) has promising potential as a drug delivery system. Here, the lung tolerability of two distinct GO varying in lateral dimensions is investigated, to reveal the most suitable candidate platform for pulmonary drug delivery. Following repeated chronic pulmonary exposure of mice to GO sheet suspensions, the innate and adaptive immune responses are studied. An acute and transient influx of neutrophils and eosinophils in the alveolar space, together with the replacement of alveolar macrophages by interstitial ones and a significant activation toward anti-inflammatory subsets, are found for both GO materials. Micrometric GO give rise to persistent multinucleated macrophages and granulomas. However, neither adaptive immune response nor lung tissue remodeling are induced after exposure to micrometric GO. Concurrently, milder effects and faster tissue recovery, both associated to a faster clearance from the respiratory tract, are found for nanometric GO, suggesting a greater lung tolerability. Taken together, these results highlight the importance of dimensions in the design of biocompatible 2D materials for pulmonary drug delivery system. © 2022 The Authors. Advanced Science published by Wiley-VCH GmbH.

View abstract
Lung recovery from DNA damage induced by graphene oxide is dependent on size, dose and inflammation profile
de Luna, LAV; Loret, T; Fordham, A; Arshad, A; Drummond, M; Dodd, A; Lozano, N; Kostarelos, K; Bussy, C Particle And Fibre Toxicology; 19 (1) 2022. 10.1186/s12989-022-00502-w. IF: 9.112
Nano-omics: nanotechnology-based multidimensional harvesting of the blood-circulating cancerome
Gardner L., Kostarelos K., Mallick P., Dive C., Hadjidemetriou M. Nature Reviews Clinical Oncology; 19 (8): 551 - 561. 2022. 10.1038/s41571-022-00645-x.

Over the past decade, the development of ‘simple’ blood tests that enable cancer screening, diagnosis or monitoring and facilitate the design of personalized therapies without the need for invasive tumour biopsy sampling has been a core ambition in cancer research. Data emerging from ongoing biomarker development efforts indicate that multiple markers, used individually or as part of a multimodal panel, are required to enhance the sensitivity and specificity of assays for early stage cancer detection. The discovery of cancer-associated molecular alterations that are reflected in blood at multiple dimensions (genome, epigenome, transcriptome, proteome and metabolome) and integration of the resultant multi-omics data have the potential to uncover novel biomarkers as well as to further elucidate the underlying molecular pathways. Herein, we review key advances in multi-omics liquid biopsy approaches and introduce the ‘nano-omics’ paradigm: the development and utilization of nanotechnology tools for the enrichment and subsequent omics analysis of the blood-circulating cancerome. © 2022, Springer Nature Limited.

View abstract
Selective brain entry of lipid nanoparticles in haemorrhagic stroke is linked to biphasic blood-brain barrier disruption
Al-Ahmady Z.S., Dickie B.R., Aldred I., Jasim D.A., Barrington J., Haley M., Lemarchand E., Coutts G., Kaur S., Bates J., Curran S., Goddard R., Walker M., Parry-Jones A., Kostarelos K., Allan S.M. Theranostics; 12 (10): 4477 - 4497. 2022. 10.7150/thno.72167.

Haemorrhagic stroke represents a significant public health burden, yet our knowledge and ability to treat this type of stroke are lacking. Previously we showed that we can target ischaemic-stroke lesions by selective translocation of lipid nanoparticles through the site of blood-brain barrier (BBB) disruption. The data we presented in this study provide compelling evidence that haemorrhagic stroke in mice induces BBB injury that mimics key features of the human pathology and, more importantly, provides a gate for entry of lipid nanoparticles-based therapeutics selectively to the bleeding site. Methods: Haemorrhagic stroke was induced in mice by intra-striatal collagenase injection. lipid nanoparticles were injected intravenously at 3 h, 24 h & 48 h post-haemorrhagic stroke and accumulation in the brain studied using in-vivo optical imaging and histology. BBB integrity, brain water content and iron accumulation were characterised using dynamic contrast-enhanced MRI, quantitative T1 mapping, and gradient echo MRI. Results: Using in-vivo SPECT/CT imaging and optical imaging revealed biphasic lipid nanoparticles entry into the bleeding site, with an early phase of increased uptake at 3-24 h post-haemorrhagic stroke, followed by a second phase at 48-72 h. Lipid nanoparticles entry into the brain post-haemorrhage showed an identical entry pattern to the trans-BBB leakage rate (Ktrans [min-1]) of Gd-DOTA, a biomarker for BBB disruption, measured using dynamic contrast-enhanced MRI. Discussion: Our findings suggest that selective accumulation of liposomes into the lesion site is linked to a biphasic pattern of BBB hyper-permeability. This approach provides a unique opportunity to selectively and efficiently deliver therapeutic molecules across the BBB, an approach that has not been utilised for haemorrhagic stroke therapy and is not achievable using free small drug molecules. © The author(s).

View abstract

2021

A method for the measurement of mass and number of graphene oxide sheets in suspension based on non-spherical approximations
Crica L.E., Dennison T.J., Guerini E.A., Kostarelos K. 2D Materials; 8 (3, 035044) 2021. 10.1088/2053-1583/abfe01. IF: 7.103

Currently, particle analysis of 2D materials in suspension is commonly restricted to microscopic techniques in the dry state, and thus does not permit an accurate investigation of colloidal suspensions. Colloids in bulk can be assessed by light scattering and diffraction to investigate features such as their hydrodynamic size, charge and concentration. However, the main drawback of such techniques lies in the application of analytical and computational methods based on models assuming particle sphericity which are not representative for 2D materials. Resonance mass measurement (RMM) is a technique which can enable the analysis of 2D materials in suspension without the assumptions of spherical models. Here, we report the application of RMM to measure particle mass and concentration for three types of graphene oxide (GO) aqueous dispersions. Using micro- and nano-suspended resonating sensors, we were able to decipher gravimetric differences between GO and graphitic materials. Our results support the urge for proper definitions and standardisations of graphene based materials, and offer a new method of characterisation for 2D material colloids in liquid suspension. © 2021 The Author(s). Published by IOP Publishing Ltd.

View abstract
Adenoviral Mediated Delivery of OSKM Factors Induces Partial Reprogramming of Mouse Cardiac Cells In Vivo
Kisby T., de Lázaro I., Fisch S., Cartwright E.J., Cossu G., Kostarelos K. Advanced Therapeutics; 4 (2, 2000141) 2021. 10.1002/adtp.202000141. IF: 0.000

The induction of in vivo reprogramming toward pluripotency has been demonstrated in several tissues utilizing either transgenic inducible mice or gene delivery approaches. However, the effects of exogenous reprogramming factor expression in the mammalian heart have not been previously reported. The present study aims to investigate the response of cardiac cells to ectopic Oct3/4, Sox2, Klf4, and cMyc (OSKM) expression in vivo using a non-integrating adenoviral vector. Direct intramyocardial injection of this vector achieves effective and transient OSKM overexpression in the healthy heart and after myocardial infarction. The expression of these factors induces transient upregulation of a number of endogenous pluripotency (endo-Oct3/4, Gdf3) and reprogramming related (Cdh1, Fut4) genes, confirming the induction of cell reprogramming. Despite the initiation of reprogramming, markers of fully de-differentiated cells including Nanog remain silenced, consistent with a partially reprogrammed state. Furthermore, no indications of tumorigenesis or teratoma formation are observed. Overall, these data suggest that adenoviral mediated OSKM delivery can be utilized to induce partial in vivo reprogramming. However, the absence of any clear regenerative effects after myocardial infarction indicates that further optimization of vector mediated reprogramming strategies is essential to overcome barriers to therapeutic efficacy. © 2020 The Authors. Advanced Therapeutics published by Wiley-VCH GmbH

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Author Correction: Graphene active sensor arrays for long-term and wireless mapping of wide frequency band epicortical brain activity
Garcia-Cortadella, R.; Schwesig, G.; Jeschke, C.; Illa, X.; Gray, Anna L.; Savage, S.; Stamatidou, E.; Schiessl, I.; Masvidal-Codina, E.; Kostarelos, K.; Guimerà-Brunet, A.; Sirota, A.; Garrido, JA. Nature Communications; 12 (1) 2021. 10.1038/s41467-021-23078-z. IF: 14.919
Deep Tissue Translocation of Graphene Oxide Sheets in Human Glioblastoma 3D Spheroids and an Orthotopic Xenograft Model
de Lázaro I., Sharp P., Gurcan C., Ceylan A., Stylianou M., Kisby T., Chen Y., Vranic S., Barr K., Taheri H., Ozen A., Bussy C., Yilmazer A., Kostarelos K. Advanced Therapeutics; 4 (1, 2000109) 2021. 10.1002/adtp.202000109. IF: 0.000

Its anatomical localization, a highly heterogeneous and drug-resistant tumor cell population and a “cold” immune microenvironment, all challenge the treatment of glioblastoma. Nanoscale drug delivery systems, including graphene oxide (GO) flakes, may circumvent some of these issues bypassing biological barriers, delivering multiple cargoes to impact several pathways simultaneously, or targeting the immune compartment. Here, the interactions of GO flakes with in vitro (U-87 MG three-dimensional spheroids, without stromal or immune compartments) and in vivo (U-87 MG orthotopic xenograft) models of glioblastoma are investigated. In vitro, GO flakes translocated deeply into the spheroids with little internalization in tumor cells. In vivo, intracranially administered GO also show extensive distribution throughout the tumor and demonstrate no impact on tumor growth and progression for the duration of the study. Internalization within tumor cells is also scarce, with the majority of flakes preferentially taken up by microglia/macrophages. The results indicate that GO flakes could offer deep and homogenous distribution throughout glioblastoma tumors and a means to target their myeloid compartment. Further studies are warranted to investigate the mechanisms of GO flakes transport within the tumor mass and their capacity to deliver bioactive cargoes but, ultimately, this information could inform the development of immunotherapies against glioblastoma. © 2020 The Authors. Published by Wiley-VCH GmbH

View abstract
Graphene active sensor arrays for long-term and wireless mapping of wide frequency band epicortical brain activity
Garcia-Cortadella R., Schwesig G., Jeschke C., Illa X., Gray A.L., Savage S., Stamatidou E., Schiessl I., Masvidal-Codina E., Kostarelos K., Guimerà-Brunet A., Sirota A., Garrido J.A. Nature Communications; 12 (1, 211) 2021. 10.1038/s41467-020-20546-w. IF: 14.919

Graphene active sensors have demonstrated promising capabilities for the detection of electrophysiological signals in the brain. Their functional properties, together with their flexibility as well as their expected stability and biocompatibility have raised them as a promising building block for large-scale sensing neural interfaces. However, in order to provide reliable tools for neuroscience and biomedical engineering applications, the maturity of this technology must be thoroughly studied. Here, we evaluate the performance of 64-channel graphene sensor arrays in terms of homogeneity, sensitivity and stability using a wireless, quasi-commercial headstage and demonstrate the biocompatibility of epicortical graphene chronic implants. Furthermore, to illustrate the potential of the technology to detect cortical signals from infra-slow to high-gamma frequency bands, we perform proof-of-concept long-term wireless recording in a freely behaving rodent. Our work demonstrates the maturity of the graphene-based technology, which represents a promising candidate for chronic, wide frequency band neural sensing interfaces. © 2021, The Author(s).

View abstract
Graphene Oxide Nanosheets Interact and Interfere with SARS-CoV-2 Surface Proteins and Cell Receptors to Inhibit Infectivity
Unal M.A., Bayrakdar F., Nazir H., Besbinar O., Gurcan C., Lozano N., Arellano L.M., Yalcin S., Panatli O., Celik D., Alkaya D., Agan A., Fusco L., Suzuk Yildiz S., Delogu L.G., Akcali K.C., Kostarelos K., Yilmazer A. Small; 17 (25, 2101483) 2021. 10.1002/smll.202101483. IF: 13.281

Nanotechnology can offer a number of options against coronavirus disease 2019 (COVID-19) acting both extracellularly and intracellularly to the host cells. Here, the aim is to explore graphene oxide (GO), the most studied 2D nanomaterial in biomedical applications, as a nanoscale platform for interaction with SARS-CoV-2. Molecular docking analyses of GO sheets on interaction with three different structures: SARS-CoV-2 viral spike (open state – 6VYB or closed state – 6VXX), ACE2 (1R42), and the ACE2-bound spike complex (6M0J) are performed. GO shows high affinity for the surface of all three structures (6M0J, 6VYB and 6VXX). When binding affinities and involved bonding types are compared, GO interacts more strongly with the spike or ACE2, compared to 6M0J. Infection experiments using infectious viral particles from four different clades as classified by Global Initiative on Sharing all Influenza Data (GISAID), are performed for validation purposes. Thin, biological-grade GO nanoscale (few hundred nanometers in lateral dimension) sheets are able to significantly reduce copies for three different viral clades. This data has demonstrated that GO sheets have the capacity to interact with SARS-CoV-2 surface components and disrupt infectivity even in the presence of any mutations on the viral spike. GO nanosheets are proposed to be further explored as a nanoscale platform for development of antiviral strategies against COVID-19. © 2021 The Authors. Small published by Wiley-VCH GmbH

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Graphene oxide prevents lateral amygdala dysfunctional synaptic plasticity and reverts long lasting anxiety behavior in rats
Franceschi Biagioni A., Cellot G., Pati E., Lozano N., Ballesteros B., Casani R., Coimbra N.C., Kostarelos K., Ballerini L. Biomaterials; 271 (120749) 2021. 10.1016/j.biomaterials.2021.120749. IF: 12.479

Engineered small graphene oxide (s-GO) sheets were previously shown to reversibly down-regulate glutamatergic synapses in the hippocampus of juvenile rats, disclosing an unexpected translational potential of these nanomaterials to target selective synapses in vivo. Synapses are anatomical specializations acting in the Central Nervous System (CNS) as functional interfaces among neurons. Dynamic changes in synaptic function, named synaptic plasticity, are crucial to learning and memory. More recently, pathological mechanisms involving dysfunctional synaptic plasticity were implicated in several brain diseases, from dementia to anxiety disorders. Hyper-excitability of glutamatergic neurons in the lateral nucleus of the amygdala complex (LA) is substantially involved in the storage of aversive memory induced by stressful events enabling post-traumatic stress disorder (PTSD). Here we translated in PTSD animal model the ability of s-GO, when stereotaxically administered to hamper LA glutamatergic transmission and to prevent the behavioral response featured in long-term aversive memory. We propose that s-GO, by interference with glutamatergic plasticity, impair LA-dependent memory retrieval related to PTSD. © 2021 The Authors

View abstract
Nanotools for Sepsis Diagnosis and Treatment
Papafilippou L., Claxton A., Dark P., Kostarelos K., Hadjidemetriou M. Advanced Healthcare Materials; 10 (1, 2001378) 2021. 10.1002/adhm.202001378. IF: 9.933

Sepsis is one of the leading causes of death worldwide with high mortality rates and a pathological complexity hindering early and accurate diagnosis. Today, laboratory culture tests are the epitome of pathogen recognition in sepsis. However, their consistency remains an issue of controversy with false negative results often observed. Clinically used blood markers, C reactive protein (CRP) and procalcitonin (PCT) are indicators of an acute-phase response and thus lack specificity, offering limited diagnostic efficacy. In addition to poor diagnosis, inefficient drug delivery and the increasing prevalence of antibiotic-resistant microorganisms constitute significant barriers in antibiotic stewardship and impede effective therapy. These challenges have prompted the exploration for alternative strategies that pursue accurate diagnosis and effective treatment. Nanomaterials are examined for both diagnostic and therapeutic purposes in sepsis. The nanoparticle (NP)-enabled capture of sepsis causative agents and/or sepsis biomarkers in biofluids can revolutionize sepsis diagnosis. From the therapeutic point of view, currently existing nanoscale drug delivery systems have proven to be excellent allies in targeted therapy, while many other nanotherapeutic applications are envisioned. Herein, the most relevant applications of nanomedicine for the diagnosis, prognosis, and treatment of sepsis is reviewed, providing a critical assessment of their potentiality for clinical translation. © 2020 The Authors. Advanced Healthcare Materials published by Wiley-VCH GmbH

View abstract
Reasons for success and lessons learnt from nanoscale vaccines against COVID-19
Kisby T., Yilmazer A., Kostarelos K. Nature Nanotechnology; 16 (8): 843 - 850. 2021. 10.1038/s41565-021-00946-9. IF: 39.213

[No abstract available]

View abstract
Shedding plasma membrane vesicles induced by graphene oxide nanoflakes in brain cultured astrocytes
Musto M., Parisse P., Pachetti M., Memo C., Di Mauro G., Ballesteros B., Lozano N., Kostarelos K., Casalis L., Ballerini L. Carbon; 176: 458 - 469. 2021. 10.1016/j.carbon.2021.01.142. IF: 9.594

Microvesicles (MVs) generated and released by astrocytes, the brain prevalent cells, crucially contribute to intercellular communication, representing key vectorized systems able to spread and actively transfer signaling molecules from astrocytes to neurons, ultimately modulating target cell functions. The increasing clinical relevance of these signaling systems requires a deeper understanding of MV features, currently limited by both their nanoscale dimensions and the low rate of their constituent release. Hence, to investigate the features of such glial signals, nanotechnology-based approaches and the applications of unconventional, cost-effective tools in generating MVs are needed. Here, small graphene oxide (s-GO) nanoflakes are used to boost MVs shedding from astrocytes in cultures and s-GO generated MVs are compared with those generated by a natural stimulant, namely ATP, by atomic force microscopy, light scattering, attenuated total reflection–fourier transform infra-red and ultraviolet resonance Raman spectroscopy. We also report the ability of both types of MVs, upon acute and transient exposure of patch clamped cultured neurons, to modulate basal synaptic transmission, inducing a stable increase in synaptic activity accompanied by changes in neuronal plasma membrane elastic features. © 2021 The Author(s)

View abstract
The impact of graphene oxide sheet lateral dimensions on their pharmacokinetic and tissue distribution profiles in mice
Jasim D.A., Newman L., Rodrigues A.F., Vacchi I.A., Lucherelli M.A., Lozano N., Ménard-Moyon C., Bianco A., Kostarelos K. Journal of Controlled Release; 338: 330 - 340. 2021. 10.1016/j.jconrel.2021.08.028. IF: 9.776

Although the use of graphene and 2-dimensional (2D) materials in biomedicine has been explored for over a decade now, there are still significant knowledge gaps regarding the fate of these materials upon interaction with living systems. Here, the pharmacokinetic profile of graphene oxide (GO) sheets of three different lateral dimensions was studied. The GO materials were functionalized with a PEGylated DOTA (1,4,7,10-tetraazacyclododecane-1,4,7,10-tetraacetic acid), a radiometal chelating agent for radioisotope attachment for single photon emission computed tomography (SPECT/CT) imaging. Our results revealed that GO materials with three distinct size distributions, large (l-GO-DOTA), small (s-GO-DOTA) and ultra-small (us-GO-DOTA), were sequestered by the spleen and liver. Significant accumulation of the large material (l-GO-DOTA) in the lungs was also observed, unlike the other two materials. Interestingly, there was extensive urinary excretion of all three GO nanomaterials indicating that urinary excretion of these structures was not affected by lateral dimensions. Comparing with previous studies, we believe that the thickness of layered nanomaterials is the predominant factor that governs their excretion rather than lateral size. However, the rate of urinary excretion was affected by lateral size, with large GO excreting at slower rates. This study provides better understanding of 2D materials in vivo behaviour with varying structural features. © 2021

View abstract
Transient reprogramming of postnatal cardiomyocytes to a dedifferentiated state
Kisby T., de Lázaro I., Stylianou M., Cossu G., Kostarelos K. PLoS ONE; 16 (5 May, e0251054) 2021. 10.1371/journal.pone.0251054. IF: 3.240

In contrast to mammals, lower vertebrates are capable of extraordinary myocardial regeneration thanks to the ability of their cardiomyocytes to undergo transient dedifferentiation and proliferation. Somatic cells can be temporarily reprogrammed to a proliferative, dedifferentiated state through forced expression of Oct3/4, Sox2, Klf4 and c-Myc (OSKM). Here, we aimed to induce transient reprogramming of mammalian cardiomyocytes in vitro utilising an OSKM-encoding non-integrating vector. Reprogramming factor expression in postnatal rat and mouse cardiomyocytes triggered rapid but limited cell dedifferentiation. Concomitantly, a significant increase in cell viability, cell cycle related gene expression and Ki67 positive cells was observed consistent with an enhanced cell cycle activation. The transient nature of this partial reprogramming was confirmed as cardiomyocyte-specific cell morphology, gene expression and contractile activity were spontaneously recovered by day 15 after viral transduction. This study provides the first evidence that adenoviral OSKM delivery can induce partial reprogramming of postnatal cardiomyocytes. Therefore, adenoviral mediated transient reprogramming could be a novel and feasible strategy to recapitulate the regenerative mechanisms of lower vertebrates. Copyright: © 2021 Kisby et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.

View abstract
Trends in Micro-/Nanorobotics: Materials Development, Actuation, Localization, and System Integration for Biomedical Applications
Wang B., Kostarelos K., Nelson B.J., Zhang L. Advanced Materials; 33 (4, 2002047) 2021. 10.1002/adma.202002047. IF: 30.849

Micro-/nanorobots (m-bots) have attracted significant interest due to their suitability for applications in biomedical engineering and environmental remediation. Particularly, their applications in in vivo diagnosis and intervention have been the focus of extensive research in recent years with various clinical imaging techniques being applied for localization and tracking. The successful integration of well-designed m-bots with surface functionalization, remote actuation systems, and imaging techniques becomes the crucial step toward biomedical applications, especially for the in vivo uses. This review thus addresses four different aspects of biomedical m-bots: design/fabrication, functionalization, actuation, and localization. The biomedical applications of the m-bots in diagnosis, sensing, microsurgery, targeted drug/cell delivery, thrombus ablation, and wound healing are reviewed from these viewpoints. The developed biomedical m-bot systems are comprehensively compared and evaluated based on their characteristics. The current challenges and the directions of future research in this field are summarized. © 2020 Wiley-VCH GmbH

View abstract

2020

Banning carbon nanotubes would be scientifically unjustified and damaging to innovation
Heller D.A., Jena P.V., Pasquali M., Kostarelos K., Delogu L.G., Meidl R.E., Rotkin S.V., Scheinberg D.A., Schwartz R.E., Terrones M., Wang Y.H., Bianco A., Boghossian A.A., Cambré S., Cognet L., Corrie S.R., Demokritou P., Giordani S., Hertel T., Ignatova T., Islam M.F., Iverson N.M., Jagota A., Janas D., Kono J., Kruss S., Landry M.P., Li Y., Martel R., Maruyama S., Naumov A.V., Prato M., Quinn S.J., Roxbury D., Strano M.S., Tour J.M., Weisman R.B., Wenseleers W., Yudasaka M. Nature Nanotechnology; 15 (3): 164 - 166. 2020. 10.1038/s41565-020-0656-y. IF: 31.538

[No abstract available]

View abstract
Graphene, other carbon nanomaterials and the immune system: toward nanoimmunity-by-design
Arianna Gazzi, Laura Fusco, Marco Orecchioni, Silvia Ferrari, Giulia Franzoni, J Stephen Yan, Matthias Rieckher, Guotao Peng, Matteo Andrea Lucherelli, Isabella Anna Vacchi, Ngoc Do Quyen Chau, Alejandro Criado, Akcan Istif, Donato Mancino, Antonio Dominguez, Hagen Eckert, Ester Vázquez, Tatiana Da Ros, Paola Nicolussi, Vincenzo Palermo, Björn Schumacher, Gianaurelio Cuniberti, Yiyong Mai, Cecilia Clementi, Matteo Pasquali, Xinliang Feng, Kostas Kostarelos, Acelya Yilmazer, Davide BedognettI, Bengt Fadeel, Maurizio Prato, Alberto Bianco and Lucia Gemma Delogu Journal of Physics: Materials; 3 (34009) 2020. 10.1088/2515-7639/ab9317. IF: 0.000
Grouping all carbon nanotubes into a single substance category is scientifically unjustified
Fadeel B., Kostarelos K. Nature Nanotechnology; 15 (3): 164. 2020. 10.1038/s41565-020-0654-0. IF: 31.538

[No abstract available]

View abstract
Intracerebral Injection of Graphene Oxide Nanosheets Mitigates Microglial Activation Without Inducing Acute Neurotoxicity: A Pilot Comparison to Other Nanomaterials
Portioli C., Bussy C., Mazza M., Lozano N., Jasim D.A., Prato M., Bianco A., Bentivoglio M., Kostarelos K. Small; 16 (48, 2004029) 2020. 10.1002/smll.202004029. IF: 11.459

Carbon-based nanomaterials (CNMs) are being explored for neurological applications. However, systematic in vivo studies investigating the effects of CNM nanocarriers in the brain and how brain cells respond to such nanomaterials are scarce. To address this, functionalized multiwalled carbon nanotubes and graphene oxide (GO) sheets are injected in mice brain and compared with charged liposomes. The induction of acute neuroinflammatory and neurotoxic effects locally and in brain structures distant from the injection site are assessed up to 1 week postadministration. While significant neuronal cell loss and sustained microglial cell activation are observed after injection of cationic liposomes, none of the tested CNMs induces either neurodegeneration or microglial activation. Among the candidate nanocarriers tested, GO sheets appear to elicit the least deleterious neuroinflammatory profile. At molecular level, GO induces moderate activation of proinflammatory markers compared to vehicle control. At histological level, brain response to GO is lower than after vehicle control injection, suggesting some capacity for GO to reduce the impact of stereotactic injection on brain. While these findings are encouraging and valuable in the selection and design of nanomaterial-based brain delivery systems, they warrant further investigations to better understand the mechanisms underlying GO immunomodulatory properties in brain. © 2020 Wiley-VCH GmbH

View abstract
Multiparametric Profiling of Engineered Nanomaterials: Unmasking the Surface Coating Effect
Gallud A., Delaval M., Kinaret P., Marwah V.S., Fortino V., Ytterberg J., Zubarev R., Skoog T., Kere J., Correia M., Loeschner K., Al-Ahmady Z., Kostarelos K., Ruiz J., Astruc D., Monopoli M., Handy R., Moya S., Savolainen K., Alenius H., Greco D., Fadeel B. Advanced Science; 7 (22, 2002221) 2020. 10.1002/advs.202002221. IF: 15.840

Despite considerable efforts, the properties that drive the cytotoxicity of engineered nanomaterials (ENMs) remain poorly understood. Here, the authors inverstigate a panel of 31 ENMs with different core chemistries and a variety of surface modifications using conventional in vitro assays coupled with omics-based approaches. Cytotoxicity screening and multiplex-based cytokine profiling reveals a good concordance between primary human monocyte-derived macrophages and the human monocyte-like cell line THP-1. Proteomics analysis following a low-dose exposure of cells suggests a nonspecific stress response to ENMs, while microarray-based profiling reveals significant changes in gene expression as a function of both surface modification and core chemistry. Pathway analysis highlights that the ENMs with cationic surfaces that are shown to elicit cytotoxicity downregulated DNA replication and cell cycle responses, while inflammatory responses are upregulated. These findings are validated using cell-based assays. Notably, certain small, PEGylated ENMs are found to be noncytotoxic yet they induce transcriptional responses reminiscent of viruses. In sum, using a multiparametric approach, it is shown that surface chemistry is a key determinant of cellular responses to ENMs. The data also reveal that cytotoxicity, determined by conventional in vitro assays, does not necessarily correlate with transcriptional effects of ENMs. © 2020 The Authors. Published by Wiley-VCH GmbH

View abstract
Nano-scavengers for blood biomarker discovery in ovarian carcinoma
Hadjidemetriou M., Papafilippou L., Unwin R.D., Rogan J., Clamp A., Kostarelos K. Nano Today; 34 (100901) 2020. 10.1016/j.nantod.2020.100901. IF: 16.907

The development and implementation of biomarker-based screening tools for ovarian cancer require novel analytical platforms to enable the discovery of biomarker panels that will overcome the limitations associated with the clinically used CA-125.The systematic discovery of protein biomarkers directly from human plasma using proteomics remains extremely challenging, due to the wide concentration range of plasma proteins. Here, we describe the use of lipid-based nanoparticles (NPs) as an ‘omics’ enrichment tool to amplify cancer signals in the blood and to uncover disease specific signatures. We aimed to exploit the spontaneous interaction of clinically-used liposomes (Caelyx®) with plasma proteins, also known as’ protein corona’ formation, in order to facilitate the discovery of previously unreported differentially abundant molecules. Caelyx® liposomes were incubated with plasma samples obtained from advanced ovarian carcinoma patients and healthy donors and corona-coated liposomes were subsequently recovered. Comprehensive comparison between ‘healthy’ and ‘diseased’ corona samples by label-free proteomics resulted in the identification of multiple differentially abundant proteins. Moreover, immunoassay-based validation of selected proteins demonstrated the potential of nanoparticle-platform proposed to discover novel molecules with great diagnostic potential. This study proposes a nanoparticle-enabled workflow for plasma proteomic analysis in healthy and diseased states and paves the way for further work needed to discover and validate panels of novel biomarkers for disease diagnosis and monitoring. © 2020

View abstract
Nanoscale nights of COVID-19
Kostarelos K. Nature Nanotechnology; 15 (5): 343 - 344. 2020. 10.1038/s41565-020-0687-4. IF: 31.538

[No abstract available]

View abstract
Nitric oxide-dependent biodegradation of graphene oxide reduces inflammation in the gastrointestinal tract
Peng G., Montenegro M.F., Ntola C.N.M., Vranic S., Kostarelos K., Vogt C., Toprak M.S., Duan T., Leifer K., Bräutigam L., Lundberg J.O., Fadeel B. Nanoscale; 12 (32): 16730 - 16737. 2020. 10.1039/d0nr03675g. IF: 6.895

Understanding the biological fate of graphene-based materials such as graphene oxide (GO) is crucial to assess adverse effects following intentional or inadvertent exposure. Here we provide first evidence of biodegradation of GO in the gastrointestinal tract using zebrafish as a model. Raman mapping was deployed to assess biodegradation. The degradation was blocked upon knockdown of nos2a encoding the inducible nitric oxide synthase (iNOS) or by pharmacological inhibition of NOS using l-NAME, demonstrating that the process was nitric oxide (NO)-dependent. NO-dependent degradation of GO was further confirmed in vitro by combining a superoxide-generating system, xanthine/xanthine oxidase (X/XO), with an NO donor (PAPA NONOate), or by simultaneously producing superoxide and NO by decomposition of SIN-1. Finally, by using the transgenic strain Tg(mpx:eGFP) to visualize the movement of neutrophils, we could show that inhibition of the degradation of GO resulted in increased neutrophil infiltration into the gastrointestinal tract, indicative of inflammation. © 2020 The Royal Society of Chemistry.

View abstract
Protein corona fingerprinting to differentiate sepsis from non-infectious systemic inflammation
Papafilippou L., Claxton A., Dark P., Kostarelos K., Hadjidemetriou M. Nanoscale; 12 (18): 10240 - 10253. 2020. 10.1039/d0nr02788j. IF: 6.895

Rapid and accurate diagnosis of sepsis remains clinically challenging. The lack of specific biomarkers that can differentiate sepsis from non-infectious systemic inflammatory diseases often leads to excessive antibiotic treatment. Novel diagnostic tests are urgently needed to rapidly and accurately diagnose sepsis and enable effective treatment. Despite investment in cutting-edge technologies available today, the discovery of disease-specific biomarkers in blood remains extremely difficult. The highly dynamic environment of plasma restricts access to vital diagnostic information that can be obtained by proteomic analysis. Here, we employed clinically used lipid-based nanoparticles (AmBisome®) as an enrichment platform to analyze the human plasma proteome in the setting of sepsis. We exploited the spontaneous interaction of plasma proteins with nanoparticles (NPs) once in contact, called the 'protein corona', to discover previously unknown disease-specific biomarkers for sepsis diagnosis. Plasma samples obtained from non-infectious acute systemic inflammation controls and sepsis patients were incubated ex vivo with AmBisome® liposomes, and the resultant protein coronas were thoroughly characterised and compared by mass spectrometry (MS)-based proteomics. Our results demonstrate that the proposed nanoparticle enrichment technology enabled the discovery of 67 potential biomarker proteins that could reproducibly differentiate non-infectious acute systemic inflammation from sepsis. This study provides proof-of-concept evidence that nanoscale-based 'omics' enrichment technologies have the potential to substantially improve plasma proteomics analysis and to uncover novel biomarkers in a challenging clinical setting.

View abstract
Size-Dependent Pulmonary Impact of Thin Graphene Oxide Sheets in Mice: Toward Safe-by-Design
Rodrigues A.F., Newman L., Jasim D., Mukherjee S.P., Wang J., Vacchi I.A., Ménard-Moyon C., Bianco A., Fadeel B., Kostarelos K., Bussy C. Advanced Science; 7 (12, 1903200) 2020. 10.1002/advs.201903200. IF: 15.840

Safety assessment of graphene-based materials (GBMs) including graphene oxide (GO) is essential for their safe use across many sectors of society. In particular, the link between specific material properties and biological effects needs to be further elucidated. Here, the effects of lateral dimensions of GO sheets in acute and chronic pulmonary responses after single intranasal instillation in mice are compared. Micrometer-sized GO induces stronger pulmonary inflammation than nanometer-sized GO, despite reduced translocation to the lungs. Genome-wide RNA sequencing also reveals distinct size-dependent effects of GO, in agreement with the histopathological results. Although large GO, but not the smallest GO, triggers the formation of granulomas that persists for up to 90 days, no pulmonary fibrosis is observed. These latter results can be partly explained by Raman imaging, which evidences the progressive biotransformation of GO into less graphitic structures. The findings demonstrate that lateral dimensions play a fundamental role in the pulmonary response to GO, and suggest that airborne exposure to micrometer-sized GO should be avoided in the production plant or applications, where aerosolized dispersions are likely to occur. These results are important toward the implementation of a safer-by-design approach for GBM products and applications, for the benefit of workers and end-users. © 2020 The Authors. Published by WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim

View abstract
Splenic Capture and in Vivo Intracellular Biodegradation of Biological-Grade Graphene Oxide Sheets
Newman L., Jasim D.A., Prestat E., Lozano N., De Lazaro I., Nam Y., Assas B.M., Pennock J., Haigh S.J., Bussy C., Kostarelos K. ACS Nano; 14 (8): 10168 - 10186. 2020. 10.1021/acsnano.0c03438. IF: 14.588

Carbon nanomaterials, including 2D graphene-based materials, have shown promising applicability to drug delivery, tissue engineering, diagnostics, and various other biomedical areas. However, to exploit the benefits of these materials in some of the areas mentioned, it is necessary to understand their possible toxicological implications and long-term fate in vivo. We previously demonstrated that following intravenous administration, 2D graphene oxide (GO) nanosheets were largely excreted via the kidneys; however, a small but significant portion of the material was sequestered in the spleen. Herein, we interrogate the potential consequences of this accumulation and the fate of the spleen-residing GO over a period of nine months. We show that our thoroughly characterized GO materials are not associated with any detectable pathological consequences in the spleen. Using confocal Raman mapping of tissue sections, we determine the sub-organ biodistribution of GO at various time points after administration. The cells largely responsible for taking up the material are confirmed using immunohistochemistry coupled with Raman spectroscopy, and transmission electron microscopy (TEM). This combination of techniques identified cells of the splenic marginal zone as the main site of GO bioaccumulation. In addition, through analyses using both bright-field TEM coupled with electron diffraction and Raman spectroscopy, we reveal direct evidence of in vivo intracellular biodegradation of GO sheets with ultrastructural precision. This work offers critical information about biological processing and degradation of thin GO sheets by normal mammalian tissue, indicating that further development and exploitation of GO in biomedicine would be possible. Copyright © 2020 American Chemical Society.

View abstract
The biomolecule corona of lipid nanoparticles contains circulating cell-free DNA
Gardner L., Warrington J., Rogan J., Rothwell D.G., Brady G., Dive C., Kostarelos K., Hadjidemetriou M. Nanoscale Horizons; 5 (11): 1476 - 1486. 2020. 10.1039/d0nh00333f. IF: 9.927

The spontaneous adsorption of biomolecules onto the surface of nanoparticles (NPs) in complex physiological biofluids has been widely investigated over the last decade. Characterisation of the protein composition of the 'biomolecule corona' has dominated research efforts, whereas other classes of biomolecules, such as nucleic acids, have received no interest. Scarce, speculative statements exist in the literature about the presence of nucleic acids in the biomolecule corona, with no previous studies attempting to describe the contribution of genomic content to the blood-derived NP corona. Herein, we provide the first experimental evidence of the interaction of circulating cell-free DNA (cfDNA) with lipid-based NPs upon their incubation with human plasma samples, obtained from healthy volunteers and ovarian carcinoma patients. Our results also demonstrate an increased amount of detectable cfDNA in patients with cancer. Proteomic analysis of the same biomolecule coronas revealed the presence of histone proteins, suggesting an indirect, nucleosome-mediated NP-cfDNA interaction. The finding of cfDNA as part of the NP corona, offers a previously unreported new scope regarding the chemical composition of the 'biomolecule corona' and opens up new possibilities for the potential exploitation of the biomolecule corona for the enrichment and analysis of blood-circulating nucleic acids. © The Royal Society of Chemistry.

View abstract

2019

Non-cytotoxic carbon nanocapsules synthesized via one-pot filling and end-closing of multi-walled carbon nanotubes
Martincic M., Vranic S., Pach E., Sandoval S., Ballesteros B., Kostarelos K., Tobias G. Carbon; 141: 782 - 793. 2019. 10.1016/j.carbon.2018.10.006. IF: 7.466

Filled carbon nanotubes (CNTs) find application in a variety of fields that expand from sensors to supercapacitors going through targeted therapies. Bulk filling of CNTs in general results in samples that contain a large amount of non-encapsulated material external to the CNTs. The presence of external material can dominate the properties of the resulting hybrids and can also induce side effects when employed in the biomedical field. Unless the encapsulated payloads have a strong interaction with the inner CNT walls, an additional step is required to block the ends of the CNTs thus allowing the selective removal of the non-encapsulated compounds while preserving the inner cargo. Herein we present a fast, easy and versatile approach that allows both filling (NaI, KI, BaI2, GdCl3 and SmCl3) and end-closing of multi-walled CNTs in a single-step, forming “carbon nanocapsules”. Remarkably the encapsulation of GdCl3 and SmCl3 leads to the formation of tubular van der Waals heterostructures. The prepared nanocapsules are efficiently internalized by cells without inducing cytotoxicity, thus presenting a safe tool for the delivery of therapeutic and dianostic agents to cells. The synergies of novel carbon and inorganic hybrid materials can be explored using the present approach. © 2018 Elsevier Ltd

View abstract

2017

Graphene in the Design and Engineering of Next-Generation Neural Interfaces
Kostarelos K., Vincent M., Hebert C., Garrido J.A. Advanced Materials; 29 (42, 1700909) 2017. 10.1002/adma.201700909. IF: 19.791

Neural interfaces are becoming a powerful toolkit for clinical interventions requiring stimulation and/or recording of the electrical activity of the nervous system. Active implantable devices offer a promising approach for the treatment of various diseases affecting the central or peripheral nervous systems by electrically stimulating different neuronal structures. All currently used neural interface devices are designed to perform a single function: either record activity or electrically stimulate tissue. Because of their electrical and electrochemical performance and their suitability for integration into flexible devices, graphene-based materials constitute a versatile platform that could help address many of the current challenges in neural interface design. Here, how graphene and other 2D materials possess an array of properties that can enable enhanced functional capabilities for neural interfaces is illustrated. It is emphasized that the technological challenges are similar for all alternative types of materials used in the engineering of neural interface devices, each offering a unique set of advantages and limitations. Graphene and 2D materials can indeed play a commanding role in the efforts toward wider clinical adoption of bioelectronics and electroceuticals. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

View abstract

2016

Gadolinium-functionalised multi-walled carbon nanotubes as a T1 contrast agent for MRI cell labelling and tracking
Servant A., Jacobs I., Bussy C., Fabbro C., Da Ros T., Pach E., Ballesteros B., Prato M., Nicolay K., Kostarelos K. Carbon; 97: 126 - 133. 2016. 10.1016/j.carbon.2015.08.051. IF: 6.198

The development of efficient contrast agents for cell labelling coupled with powerful medical imaging techniques is of great interest for monitoring cell trafficking with potential clinical applications such as organ repair and regenerative medicine. In this paper, functionalised multi-walled carbon nanotubes (MWNTs) were engineered for cell labelling in T1-weighted MRI applications. These sophisticated constructs were covalently functionalised with the gadolinium (Gd) chelating agent, diethylene triamine pentaacetic acid (DTPA), enabling tight attachment of Gd atoms onto the nanotube surface. The resulting Gd-labelled MWNTs were found to be stable over 2 weeks in water and mouse serum and high payload of Gd atoms could be loaded onto the nanotubes. The r1 relaxivity of the Gd-MWNTs was a 3-fold higher than of the clinically approved T1 contrast agent Magnevist at a magnetic field strength of 7T. The contrast efficiency, expressed as the r1 relaxivity, of the Gd-MWNTs in Human Umbilical Vein Endothelial cells (HUVEC) was investigated at 7T and was found to be around 6.6 mM-1 s-1. There was no reduction of the contrast efficiency after internalisation in HUVECs, which was imparted to the ability of carbon nanotubes to translocate the cell membrane. © 2015 The Authors. Published by Elsevier Ltd.

View abstract

2010

Filled and glycosylated carbon nanotubes for in vivo radioemitter localization and imaging
You Hong, S.; Tobias, G.; Al-Jamal, K.T.; Ballesteros, B.; Ali-Boucetta, H.; Lozano-Perez, S.; Nellist, P.D.; Sim, R.B.; Finucane, C.; Mather, S.J.; Green, M.L.H.; Kostarelos, K.; Davis, B.G. Nature Materials; 2010. .