Emerging Graphitic Carbon Nitride-based Nanobiomaterials for Biological Applications

Graphitic carbon nitride (g-CN) based nanostructures are distinctive materials with unique compositional, structural, optical, and electronic properties with exceptional band structure, moderate surface area, and exceptional thermal and chemical stability. Because of these properties, g-CN based nanomaterials have shown promising applications and higher performance in the biological avenue. This review covers the state-of-the-art synthetic strategies used for the preparation of the materials, the basic structure, and a panorama of different optimization strategies leading to improved physicochemical properties responsible for the biological application. The following sections include the recent progress in the use of g-CN based nanobiomaterials for biosensors, bioimaging, photodynamic therapy, drug delivery, chemotherapy, and the antimicrobial segment. Furthermore, we have summarized the role and evaluation of biosafety and biocompatibility of the material. Finally, the unresolved issues, plausible challenges, current status, and future perspectives for the development and design of g-CN have been summarized and are expected to promote a clinical path for the medical sector and human well-being.

Nanodrugs with intrinsic radioprotective exertion: Turning the double-edged sword into a single-edged knife

Ionizing radiation (IR) poses a growing threat to human health, and thus ideal radioprotectors with high efficacy and low toxicity still receive widespread attention in radiation medicine. Despite significant progress made in conventional radioprotectants, high toxicity, and low bioavailability still discourage their application. Fortunately, the rapidly evolving nanomaterial technology furnishes reliable tools to address these bottlenecks, opening up the cutting-edge nano-radioprotective medicine, among which the intrinsic nano-radioprotectants characterized by high efficacy, low toxicity, and prolonged blood retention duration, represent the most extensively studied class in this area. Herein, we made the systematic review on this topic, and discussed more specific types of radioprotective nanomaterials and more general clusters of the extensive nano-radioprotectants. In this review, we mainly focused on the development, design innovations, applications, challenges, and prospects of the intrinsic antiradiation nanomedicines, and presented a comprehensive overview, in-depth analysis as well as an updated understanding of the latest advances in this topic. We hope that this review will promote the interdisciplinarity across radiation medicine and nanotechnology and stimulate further valuable studies in this promising field.

Fullerenes for the treatment of cancer: an emerging tool

Cancer is a most common cause of mortality globally. Available medicines possess severe side effects owing to their non-specific targeting. Hence, there is a need of an alternative in the healthcare system that should have high efficacy with the least side effects, also having the ability to achieve site-specific targeting and be reproducible. This is possible with the help of fullerenes. Fullerenes are having the unique physicochemical and photosensitizer properties. This article discusses the synthesis, functionalization, mechanism, various properties, and applications of C60 fullerenes in the treatment of cancer. The review article also addresses the various factors influencing the activity of fullerenes including the environmental conditions, toxicity profile, and future prospective.

Photodynamic Activity of Fullerene Derivatives Solubilized in Water by Natural-Product-Based Solubilizing Agents

Water-soluble fullerenes prepared by using solubilizing agents based on natural products are promising photosensitizers for photodynamic therapy. Cyclodextrin, β-1,3-glucan, lysozyme, and liposomes can stably solubilize not only C₆₀ and C₇₀ , but also some C₆₀ derivatives in water. To improve the solubilities of fullerenes, specific methods have been developed for each solubilizing agent. Water-soluble C₆₀ and C₇₀ exhibit photoinduced cytotoxicity under near-ultraviolet irradiation, but not at wavelengths over 600 nm, which are the appropriate wavelengths for photodynamic therapy. However, dyad complexes of solubilized C₆₀ derivatives combined with light-harvesting antenna molecules improve the photoinduced cytotoxicities at wavelengths over 600 nm. Furthermore, controlling the fullerene and antenna molecule positions within the solubilizing agents affects the performance of the photosensitizer.

Biological applications of hydrophilic C60 derivatives (hC60s)- a structural perspective

Reactive oxygen species (ROS) generation and radical scavenging are dual properties of hydrophilic C60 derivatives (hC60s). hC60s eliminate radicals in dark, while they produce reactive oxygen species (ROS) in the presence of irradiation and oxygen. Compared to the pristine C60 suspension, the aqueous solution of hC60s is easier to handle in vivo. hC60s are diverse and could be placed into two general categories: covalently modified C60 derivatives and pristine C60 solubilized non-covalently by macromolecules. In order to present in detail, the above categories are broken down into 8 parts: C60(OH)n, C60 with carboxylic acid, C60 with quaternary ammonium salts, C60 with peptide, C60 containing sugar, C60 modified covalently or non-covalently solubilized by cyclodextrins (CDs), pristine C60 delivered by liposomes, functionalized C60-polymer and pristine C60 solubilized by polymer. Each hC60 shows the propensity to be ROS producer or radical scavenger. This preference is dependent on hC60s structures. For example, major application of C60(OH)n is radical scavenger, while pristine C60/γ-CD complex usually serves as ROS producer. In addition, the electron acceptability and innate hydrophobic surface confer hC60s with O2 uptake inhibition, HIV inhibition and membrane permeability. In this review, we summarize the preparation methods and biological applications of hC60s according to the structures.