Abstract
For the investigation of biomolecular processes in- and outside of cells there is a steadily increasing importance of fluorescent biomarkers. Many different fluorescent biomarkers are available, but most of them do not fulfil all of the required physical and optical properties. Recent studies show nanodiamonds as promising red fluorescent biomarkers. Nanodiamonds seem to surpass organic dyes and fluorescent proteins in terms of photo bleaching properties and quantum dots in terms of cell cytotoxicity. In this study we present optical properties of green fluorescent nanodiamonds of a diameter of about 25 nm. As a proof of concept we modified the surface of the nanodiamonds with antibodies to biofunctionalise them for specific targeting to biomolecules. We show the successful transfection of nanodiamond immunoconjugates in JIMT-1 cells.