An ascorbic acid sensor based on cadmium sulphide quantum dots

Abstract

We present a Förster resonance energy transfer (FRET)-based fluorescence detection of vitamin C [ascorbic acid (AA)] using cadmium sulphide quantum dots (CdS QDs) and diphenylcarbazide (DPC). Initially, DPC was converted to diphenylcarbadiazone (DPCD) in the presence of CdS QDs to form QD-DPCD. This enabled excited-state energy transfer from the QDs to DPCD, which led to the fluorescence quenching of QDs. The QD-DPCD solution was used as the sensor solution. In the presence of AA, DPCD was converted back to DPC, resulting in the fluorescence recovery of CdS QDs. This fluorescence recovery can be used to detect and quantify AA. Dynamic range and detection limit of this sensing system were found to be 60-300 nM and 2 nM, respectively. We also performed fluorescence lifetime analyses to confirm existence of FRET. Finally, the sensor responded with equal accuracy to actual samples such as orange juice and vitamin C tablets. Graphical abstract Schematic showing the FRET based fluorescence detection of ascorbic acid.

One-step hydrothermal synthesis of thioglycolic acid capped CdS quantum dots as fluorescence determination of cobalt ion

“…TGA@CdS QDs were prepared via a classic hydrothermal method as previously described in report 29 . Briefly, 0.7458 g cadmium chloride hydrate (CdCl 2 ·2.5H 2 O) and 0.4400 g thiourea (CH 4 N 2 S) were dissolved in 280 mL deionized water and stirring for 30 min.…”

CdS nanocrystals as fluorescent probe for detection of dolasetron mesylate in aqueous solution: Application to biomedical analysis

“…Very recently, a Förster resonance energy transfer (FRET)-based fluorescence detection of ascorbic acid (AA) has been developed using CdS QDs and diphenylcarbazide (DPC). The present FRET-based CdS QD probe showed an unprecedented LOD of 2 nM with a dynamic range of 60–300 nM for AA detection [31] .…”

“…In 1998, Bruchez and co-workers [11] and Chan and Nie [12] were the first to recognize the applications of QDs for biology. So far, many fluorescence-based methods have been developed by using semiconducting QDs for analysis of ions [13] , [14] , [15] , [16] , bioimaging [17] , [18] , [19] , [20] , [21] , biosensing [22] , [23] , [24] , [25] , pharmaceutical analysis [26] , [27] , [28] , [29] , [30] , [31] and explosives [32] .…”

Controllable Photodynamic Therapy Implemented by Regulating Singlet Oxygen Efficiency

“…FRET was used for the structural analysis of DNA,33 protein,34 targeted therapy,35 fluorescent probe,36 biosensors37 etc 38. When there is a spectral overlap between energy donor (D, emission spectrum) and energy acceptor (A, acceptor absorption), the fluorescence of the donor will be quenched, and the fluorescence of the energy acceptor will be observed ( Figure 8 ).…”