Functionalized carbon dots from zein biopolymer as a sensitive and selective fluorescent probe for determination of sumatriptan

Functionalizing the surface of nanomaterials with certain recognition units is a promising method for the fabrication of new fluorescent nanosensors for target analysis. In this work, a fluorescent nanosensor was successfully fabricated through conjugating 3,5-dinitro benzoyl chloride with raw carbon dots (CDs) which were first prepared from zein biopolymer and their characteristics have been evaluated using various techniques such as high-resolution transmission electron microscopy, FT-IR, UV-Vis spectroscopy, fluorescence spectrophotometery and X-ray photoelectron spectroscopy. The prepared DNB-CDs have been used to develop a new, sensitive, simple, cost effective and selective probe for detection of sumatriptan. The proposed method relies on fluorescence quenching of modified carbon dots in the presence of sumatriptan. Modified carbon dot showed maximum emission at 446 nm. Stern-Volmer was obeyed in the concentration range of 1-15 nM with desirable limit of detection (0.32 nM) and selectivity toward sumatriptan. Commercially available tablets and human urine samples were successfully analyzed to investigate practical applicability of the proposed sensor in real samples.