Detection of ascorbic acid and folic acid based on water-soluble CuInS2 quantum dots

Abstract

In this paper, water-soluble CuInS(2) ternary quantum dots (QDs) modified by mercaptopropionic acid (MPA) were directly synthesized by hydrothermal method. Ascorbic acid (AA) can induce the fluorescence enhancement of MPA-capped CuInS(2) QDs and can be used for the detection of AA. Under the optimized conditions, the relationship between the fluorescence intensity of the CuInS(2) QDs and AA concentration was linear in the range of 0.25-200 μmol L(-1). Most relevant molecules and physiological ions had no effect on the detection of AA. The fluorescence intensity of CuInS(2) QDs enhanced by a certain amount of AA could be reduced in the presence of folic acid (FA) and thus can be used for the detection of FA with the linear range of 0.2-100 μmol L(-1). Compared with previous reports, the established approach utilized a simple, sensitive, and selective strategy to develop the QDs probe based on fluorescence enhancing and quenching phenomena without complicated immobilization.

Turn-on fluorescence probe for selective and sensitive detection of d-penicillamine by CdS quantum dots in aqueous media: Application to pharmaceutical formulation

“…In this connection, many mechanisms have been proposed for the design of sensors for various analytes, such as inorganic ions [37,38,[53][54][55][56][57], biomolecules [22,30,33] and active pharmaceutical ingredients [34,35] based on the surface states fluorescence modulation of QDs. Similarly, herein we have suggested that same approach can also be utilized for turn-on sensing of d-PA based on MPA-CdS QDs.…”

“…Recently, the studies on detecting and identifying biomolecules with QDs such as CdS, CdSe, CdTe, CuInS 2 etc. as optical sensors have attracted considerable attention [22][23][24][25][26][27][28][29]. Wang et al [30] has reported the fluorescent probe for cystein based on citrate (Cit)-capped CdS quantum dots (QDs) and it offers good sensitivity and selectivity for detecting cystein.…”

11-Mercaptoundecanoic acid capped gold nanoclusters as a fluorescent probe for specific detection of folic acid via a ratiometric fluorescence strategy

“…FA with different concentrations were introduced into the diluted plasma samples to prepare the spiked samples. 27,28 Human blood serum samples were obtained from Medical College of Beihua University, China, and all analyses were performed at the Nanotechnology & Application Laboratory. All experiments were performed in compliance with the relevant laws and national guidelines (Ethical Guidelines for Biomedical Research on Human Participants, provided by China National Health and Family Planning commission), and the ethical clearance for the same was provided by the Medical College of Beihua University, Jilin City.…”

Rapid and sensitive colorimetric detection of ascorbic acid in food based on the intrinsic oxidase‐like activity of MnO2 nanosheets

“…Electrochemistry 0-5000 0.61 [43] Electrospraying method 0-1000 7.35 [44] Fluorescence quenching 8-10 2.4 [45] Ratiometrically fluorescent 3-40 1.5 [46] Fluorescence enhancement 250-200 50 [47] Fluorescence turn on 2-100 0.17 [48] Colorimetry 0.1-2.5 0.049 [14] Colorimetric sensor 0.25-20 0.062 This method investigated using the same experimental conditions. As shown in Fig.…”