The unique physical, chemical and electronic properties of carbon nanotubes (CNTs) have generated much interest in their potential medical applications. Now, new toxicological and pharmacological ...studies suggest guidelines for the safe use of carbon nanotubes in medicine.
Currently, a broad interdisciplinary research effort is pursued on biomedical applications of 2D materials (2DMs) beyond graphene, due to their unique physicochemical and electronic properties. The ...discovery of new 2DMs is driven by the diverse chemical compositions and tuneable characteristics offered. Researchers are increasingly attracted to exploit those as drug delivery systems, highly efficient photothermal modalities, multimodal therapeutics with non‐invasive diagnostic capabilities, biosensing, and tissue engineering. A crucial limitation of some of the 2DMs is their moderate colloidal stability in aqueous media. In addition, the lack of suitable functionalisation strategies should encourage the exploration of novel chemical methodologies with that purpose. Moreover, the clinical translation of these emerging materials will require undertaking of fundamental research on biocompatibility, toxicology and biopersistence in the living body as well as in the environment. Here, a thorough account of the biomedical applications using 2DMs explored today is given.
Different classes of two‐dimensional materials are emerging as biomaterial alternatives to graphene due to their unique physicochemical properties and their good biocompatibility. Currently, applications including anticancer therapeutics, multimodal bioimaging, cancer theranostics, biosensing, tissue engineering, and antimicrobial coatings are explored. However, there are still several concerns and new challenges ahead of these materials before their translation into clinical use.
In this Review, we attempt to offer a thorough description of all of the chemical components and the rationale behind the design of temperature-sensitive vesicle systems, as well as the critical ...pharmacological parameters that need to be combined to achieve their successful clinical translation. The focus of this Review will be predominantly on the design principles around the construction of temperature-sensitive liposomes (TSL) and their use in combination with external local hyperthermia to achieve heat-triggered drug release. The emphasis lies on the chemical components synthesized and incorporated in the design and engineering of TSL. We conclude that the development of TSL with ultrafast drug release capabilities needs to progress in parallel with vesicle pharmacokinetic profiling, imaging, and monitoring capacity and technologies for accurate temperature elevation and control. The development of heat-triggered liposome systems offer the greatest opportunity for clinical translation of the next generation, nanoscale “smart” vesicle systems of enhanced functionality, following from the successful legacy and rich clinical history from multiple earlier liposome technologies.
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.
The design and fabrication, functionalization, actuation, and tracking of individual and a swarm of micro/nanorobots are an indispensable part for achieving biomedical applications. How to combine and integrate all the four aspects together and realize a biomedical therapeutic function using the micro‐/nanorobotic strategy is discussed.
Exploring the Interface of Graphene and Biology Kostarelos, Kostas; Novoselov, Kostya S.
Science (American Association for the Advancement of Science),
04/2014, Letnik:
344, Številka:
6181
Journal Article
Recenzirano
To take advantage of the properties of graphene in biomedical applications, well-defined materials need to be matched with intended applications.
Graphene is highly conductive, flexible, and has ...controllable permittivity and hydrophilicity, among its other distinctive properties (
1
,
2
). These properties could enable the development of multifunctional biomedical devices (
3
). A key issue for such applications is the determination of the possible interactions with components of the biological milieu to reveal the opportunities offered and the limitations posed. As with any other nanomaterial, biological studies of graphene should be performed with very specific, well-designed, and well-characterized types of materials with defined exposure. We outline three layers of complexity that are interconnected and need to be considered carefully in the development of graphene for use in biomedical applications: material characteristics; interactions with biological components (tissues, cells, and proteins); and biological activity outcomes.
Nanoparticles (NPs) are instantly modified once injected in the bloodstream because of their interaction with the blood components. The spontaneous coating of NPs by proteins, once in contact with ...biological fluids, has been termed the 'protein corona' and it is considered to be a determinant factor for the pharmacological, toxicological and therapeutic profile of NPs. Protein exposure time is thought to greatly influence the composition of protein corona, however the dynamics of protein interactions under realistic, in vivo conditions remain unexplored. The aim of this study was to quantitatively and qualitatively investigate the time evolution of in vivo protein corona, formed onto blood circulating, clinically used, PEGylated liposomal doxorubicin. Protein adsorption profiles were determined 10 min, 1 h and 3 h post-injection of liposomes into CD-1 mice. The results demonstrated that a complex protein corona was formed as early as 10 min post-injection. Even though the total amount of protein adsorbed did not significantly change over time, the fluctuation of protein abundances observed indicated highly dynamic protein binding kinetics.
Many consider carbon nanomaterials the poster children of nanotechnology, attracting immense scientific interest from many disciplines and offering tremendous potential in a diverse range of ...applications due to their extraordinary properties. Graphene is the youngest in the family of carbon nanomaterials. Its isolation, description, and mass fabrication has followed that of fullerenes and carbon nanotubes. Graphene’s development and its adoption by many industries will increase unintended or intentional human exposure, creating the need to determine its safety profile. In this Account, we compare the lessons learned from the development of carbon nanotubes with what is known about graphene, based on our own investigations and those of others. Despite both being carbon-based, nanotubes and graphene are two very distinct nanomaterials. We consider the key physicochemical characteristics (structure, surface, colloidal properties) for graphene and carbon nanotubes at three different physiological levels: cellular, tissue, and whole body. We summarize the evidence for health effects of both materials at all three levels. Overall, graphene and its derivatives are characterized by a lower aspect ratio, larger surface area, and better dispersibility in most solvents compared to carbon nanotubes. Dimensions, surface chemistry, and impurities are equally important for graphene and carbon nanotubes in determining both mechanistic (aggregation, cellular processes, biodistribution, and degradation kinetics) and toxicological outcomes. Colloidal dispersions of individual graphene sheets (or graphene oxide and other derivatives) can easily be engineered without metallic impurities, with high stability and less aggregation. Very importantly, graphene nanostructures are not fiber-shaped. These features theoretically offer significant advantages in terms of safety over inhomogeneous dispersions of fiber-shaped carbon nanotubes. However, studies that directly compare graphene with carbon nanotubes are rare, making comparative considerations of their overall safety and risk assessment challenging. In this Account, we attempt to offer a set of rules for the development of graphene and its derivatives to enhance their overall safety and minimize the risks for adverse reactions in humans from exposure. These rules are: (1) to use small, individual graphene sheets that macrophages in the body can efficiently internalize and remove from the site of deposition; (2) to use hydrophilic, stable, colloidal dispersions of graphene sheets to minimize aggregation in vivo; and (3) to use excretable graphene material or chemically-modified graphene that can be degraded effectively. Such rules can only act as guidelines at this early stage in the development of graphene-based technologies, yet they offer a set of design principles for the fabrication and safe use of graphene material that will come in contact with the human body. In a broader context, the safety risks associated with graphene materials will be entirely dependent on the specific types of graphene materials and how they are investigated or applied. Therefore, generalizations about the toxicity of “graphene” as a whole will be inaccurate, possibly misleading, and should be avoided.
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