Fluorescent nanodiamonds for biological applications

Biomedical imaging often involves the use of fluorophores, bright optical labels which enable observation of objects which are otherwise invisible. Conventional fluorophores include fluorescein, rhodamine, fluorescent proteins and quantum dots; however, often these are limited by cytotoxicity, pH sensitivities, brightness or photo bleaching/blinking [1]. Colour centres in nanodiamonds have many properties which make them attractive for biological applications including their chemical and physical stability, biocompatibility, easy surface modification and their optical and magnetic spin properties.