Quantitative fluorescent determination of DNA – Ochratoxin a interactions supported by nitrogen-vacancy rich nanodiamonds

Abstract

Ochratoxin A (OTA) is a hazardous contaminant of a large variety of plant and animal originated food. Herein, we report an interaction of OTA with calf thymus DNA (ct DNA) on the nanodiamond surface. We employed multispectroscopic techniques to elucidate the binding mechanism of OTA with ct DNA. The fluorescence and UV–Vis spectroscopy results show that OTA binds to ds ct DNA and forms complexes.We obtained the binding constants of OTA and ct DNA using fluorescence quenching and UV–Vis spectroscopy. The binding constant (Kb) for the interaction of OTA with ct DNA was determined using spectroscopic methods and was determined as 3.27 × 105 M−1 (UV–Vis) and 8.12 × 105 M−1 (fluorescence) for nanodiamond in green tea beverage OTA. Performed analyses directly indicate that OTA can interact with calf thymus DNA in a groove-binding mode as proved by the hyperchromic effect of the absorption spectra. This study of OTA–ct DNA interaction may provide novel insights into the toxicological effect of the mycotoxins.