Fluorescent determination of trinitrotoluene with bovine serum albumin mediated enhancement of thioglycolic acid capped cadmium selenium quantum dots

Abstract

Here, a spectroscopic investigation of the interaction between bovine serum albumin protein and thioglycolic acid capped cadmium selenide (CdSe) quantum dots is presented. Luminescent water-soluble CdSe quantum dots were synthesized at room temperature by a one-step proctocol. Selenium powder and thioglycolic acid were used as the precursor and stabilizer, respectively. The synthesized thioglycolic acid capped CdSe quantum dots were activated by 1-ethyl-3-(3-dimethylaminopropyl) carbodiimide hydrochloride/N-hydroxysuccinimide treatment and conjugated with bovine serum albumin protein. The fluorescence signal of CdSe quantum dots was enhanced proportionally with the bovine serum albumin concentration from 0.25 to 5 µg/mL. This nano-bioconjugate was employed for the determination of trinitrotoluene with a detection limit of 5.65 ppm trinitrotoluene across a linear range of 4.4 × 10−6 M to 35.2 × 10−6 M.