Adoption of nanodiamonds as biomedical materials for bone repair

Abstract

Keywords: gene/drug delivery • nanodiamonds • therapeutics Nanodiamonds (NDs) are an emerging class of biologically compatible carbon-based nanomaterials that possess a set of unique properties essential for the design of innovative therapies in the fields of drug delivery, tissue engineering and bioimaging [1]. For instance, the high surface area along with the tunable surface chemistry enables the physical adsorption or covalent conjugation of a variety of therapeutic molecules, such as drugs, peptides and growth factors [2][3][4][5]. Additionally, NDs' surface can be modified with targeting biological signals to achieve a selective cellular internalization of chemotherapeutic agents as well as genetic materials. Aside from their role as carriers in drug and gene delivery, NDs have been widely explored as nanofillers to improve the physical and mechanical properties of both natural and synthetic scaffolds [6,7]. Specifically, NDs have found application in the field of bone tissue engineering as reinforcing nanomaterial to design nanocomposite systems necessary to promote bone regeneration. This editorial emphasizes on the current state-of-the-art research using NDs in the field of bone repair, with a focus on the recent breakthroughs such as precise immobilization of growth factors and peptides. Biomolecule immobilization via surface functionalization of NDsNDs are carbon-based nanomaterials, which possess a set of unique properties that enables their use in a variety of applications including drug delivery, tissue engineering and bioimaging. This advantage has encouraged scientists to investigate NDs for a broad range of applications [8] in regenerative medicine with a primary focus on bone tissue engineering. NDs possess versatile surface functionalities and they can be loaded with virtually any type of biomolecule, thereby enabling their use as delivery vehicles in bone-healing applications [9]. The presence of surface functional groups can efficiently control the interfacial reactions between the nanoparticle and the active biomolecule, eventually maximizing the therapeutic efficiency of the delivered biomaterial. The initial functional groups present on the surface of NDs, following the formation of the nanoparticle, vary according to the selected synthesis and purification methods. For example, hydrogen-assisted chemical vapor deposition generates NDs bearing hydrogen-terminated surfaces. On the other hand, methods, such as detonation synthesis, introduce a highly diverse surface chemistry, with functional groups such as hydroxyl, carbonyl, ether and carboxyl groups. It is essential to maintain a similar functionality throughout the entire surface to enable further surface reactions. Thus, chemical treatment of the NDs is often required to create homogenized reactive surfaces. Among the possible alternatives, carboxylation, hydroxylation or hydrogenation are the commonly investigated routes to generate -COOH and -OH groups on the surface. Due to the presence of these diverse functionalities on the surfac...

Smart and Functionalized Development of Nucleic Acid‐Based Hydrogels: Assembly Strategies, Recent Advances, and Challenges

“…At present, NAHs as a promising controllable delivery system has been applied to load several types of cargoes, such as nucleic acid drugs, small-molecule drugs, and other specific biomaterials or tools, which mainly perform their functions in gene therapy, [210][211][212][213] immunotherapy, [43,[214][215][216][217] and chemotherapy. [86,208,[218][219][220][221] In recent years, with deep investigations of the microenvironment alteration near different lesions, the treatment protocols with smart administration systems have made great progress in the delivery of nucleic acid drugs, chemodrugs, and certain small drugs. The stimuli-responsive DNA hydrogels as novel smart delivery carriers have come to the foreground and several environment triggers have been explored for driving the drug delivery systems, such as pH, [219] light, [220] and magnetic field.…”

“…[86,208,[218][219][220][221] In recent years, with deep investigations of the microenvironment alteration near different lesions, the treatment protocols with smart administration systems have made great progress in the delivery of nucleic acid drugs, chemodrugs, and certain small drugs. The stimuli-responsive DNA hydrogels as novel smart delivery carriers have come to the foreground and several environment triggers have been explored for driving the drug delivery systems, such as pH, [219] light, [220] and magnetic field. [84,86] In the newly-reported study of Zhang et al, [219] they constructed a pHresponsive NAH with gemcitabine (Ge)-i-motif which was synthesized by replacing deoxycytidine (dC) with its nucleoside analog Ge (Figure 10A).…”

“…Reproduced with permission. [220] Copyright 2015, The Royal Society of Chemistry. C) Cas 9-mRNA embedded NAHs for genome editing.…”

“…Most recently, another type of smart hybrid DNA hydrogel was created for the delivery of therapeutic molecules to restore the functionality of damaged tissues. [220] The study designed a nanocomposite DNA-based hydrogel cross-linked with oxidized alginate (OA) through the formation of reversible imine linkages. The formulated hydrogel with optimized ratios functioned as an injectable carrier for the sustained delivery of a small molecule drug, simvastatin, for more than a week.…”

Synthesis of Multi-Stimuli Responsive Fe3O4 Coated with Diamonds Nanocomposite for Magnetic Assisted Chemo-Photothermal Therapy

“…Nanodiamond is among the least toxic of all carbon-based nanomaterials tested so far [ 9 , 10 ] and is a potential nanomedicine platform that can bypass the drug efflux mechanisms of tumor cells and enhance intracellular drug retention [ 8 , 11 ]. Recently, drug delivery system-based nanodiamonds (NDs) have attracted growing attention for their superior biocompatibility, chemical stability, and drug accommodating ability [ 12 , 13 , 14 , 15 ].…”