Nanodiamond-Based Materials for Biomedical Sensors and Drug Delivery

Nanodiamonds (NDs) are a nanoscale of diamond material with a diam eter ranging from 1 to 150 nm. It has a large surface area, and high chemical and physical stability. In this chapter, the authors will present the application of nanodiamond-based material for biomedical sensors and drug delivery. The use of nanodiamonds in the biomedical field for the diagnosis and treatment of diseases depends on their large surface area for conjugation with the drug molecules, nontox icity, structure with brilliant biocompatibility, and spectroscopic properties. Nanodiamond has unsaturated bonds of carbon on its surface and extraordinary adsorption and chemical-linking capabilities that interact with the molecules of interest such as annonacin, squamocin, and quercetin. Several studies have shown good results when nanodiamond is used as a carrier of drugs in cancers and other disease treatments. Due to its biocompatibility property, there is a possibility that nanodiamonds can be used as a carrier to deliver drugs or bioactive compounds to the tumor microenvironment and therefore enhance its anticancer activity. Meanwhile, nanodiamonds can also be doped with boron to give a catalytic activity for electrochemical sensor application. Boron-doped nanodiamond has unique properties, such as large specific surface area, low background current, and fast electron transfer. Furthermore, this sensor can be applied in a wide range of applica tions in the electrochemical analysis of drugs such as fluoroquinolone-type antibi otic sensors, glucose sensors, artificial sweetener sensors, and many more. The sensor provides selective and sensitive properties, which is mandatory for sensor application.