Determination of Hydrocortisone in Cosmetics by CdSe/CdS Quantum Dots‐Based Fluoroimmunoassay Using Magnetic Fe₃O₄/Au Nanoparticles as Solid Carriers

Abstract

This work demonstrated the feasibility of detecting hydrocortisone in cosmetics using a novel CdSe/CdS quantum dots-based competitive fluoroimmunoassay with magnetic core/shell Fe 3 O 4 /Au nanoparticles (MCFN) as solid carriers. Hydrocortisone antigen was labeled with the synthesized core/shell CdSe/CdS quantum dots (QDs) to form the antigen-QDs conjugate. Meanwhile, hydrocortisone antibody was incubated with MCFN and the immobilized antibody was obtained. The immobilized antibody was then mixed sequentially with hydrocortisone and a slightly excess amount of the QDs-labeled hydrocortisone antigen, allowing their competition for binding with the antibody immobilized on MCFN. The bound hydrocortisone and the antigen-QDs conjugates on MCFN were removed subsequently after the mixture was applied to a magnetic force. The analyte concentration was obtained by measuring the fluorescence intensity of the unbound hydrocortisone antigen-QDs conjugates. The proposed method was characterized by simplicity, rapidity, and high sensitivity with a wide linear working range of 0.5 to 15000 pg•mL -1 and a low detection limit of 0.5 pg•mL -1 . The proposed method was successfully applied to the determination of hydrocortisone in cosmetics with satisfactory results.

Multifunctional Magnetoplasmonic Nanomaterials and Their Biomedical Applications

“…11(B)). 158 A spread of a 10-L drop of a mixture of 10 5 cfu/mL bacteria and 3 g/mL Fe 3 O 4 @Au NPs on a silicon surface can be effectively condensed into a highly compact dot within 5 min by applying an external point magnetic field, resulting in 60 times more concentrated bacteria in the dot area than on the spread area 159 demonstrated the feasibility of detecting hydrocortisone in cosmetics using a novel CdSe@CdS quantum dot-based competitive fluoroimmunoassay with magnetic core-shell Fe 3 O 4 @Au NPs as solid carriers. The analyte concentration was quantified by measuring the fluorescence intensity of the unbound hydrocortisone antigen-QDs conjugates.…”

Current trends in liquid–liquid and solid–liquid extraction for cosmetic analysis: a review

“…Conventional liquid-liquid and solid-liquid extraction-based procedures are common strategies for sample preparation in both official and published methods. [7][8][9][10][11][12][13][17][18][19][20][21][22][23][24][25][26][27][28][29][30][31][32] Nevertheless, they present some disadvantages. Generally, extraction procedures involve the use of high volumes (5 to 60 mL) of toxic organic solvents such as tetrachloromethane, chloroform, dichloromethane diethyl ether, methanol, etc.…”

“…34 In many cases, additional stages such as shaking, heating, centrifugation and ltration are necessary resulting in laborintensive and time-consuming procedures. [17][18][19][20][21][22] For example, have recently developed an extraction method for the determination of hydrocortisone in cosmetics: 50 g of sample is stirred with 200 mL of methanol until homogeneous dispersion of the sample; aer centrifugation and ltration, the solvent is evaporated; the residue is solubilized in 100 mL of ethylacetate, stirred for 1 h, ltered, dried again and re-solubilized in 1 mL methanol. 21 This long procedure, which limits sample throughput, is necessary in order to improve sample clean up.…”

“…Classical treatments (traditional and long-established treatments), such as acid digestion, conventional liquid-liquid extraction, distillation etc., are the most used. [7][8][9][10][11][12][13][17][18][19][20][21][22][23][24][25][26][27][28][29][30][31][32] Current trends (considering the most recent advances) in sample preparation such as development of simpler, miniaturized and automated solvent-free procedures are being gradually introduced in cosmetic analysis. As a consequence, faster and greener methods with a higher degree of sample cleanup with regard to classical procedures are being designed.…”

Development of a competitive indirect ELISA for high-throughput screening of hydrocortisone in cosmetic sample

“…The ELISA methods have proven to be a rapider and lower-cost screening tool for compound residues with lower detection limits and easier pretreatment in comparing with instrumental methods (Luo et al, 2015;Song et al, 2019). Until now, the research about the development for immunoassays method for HYD by fluoro-immunoassay (Wang, Wei, Tao, & Dai, 2011), enzyme-linked immunosorbent assay and immunochromatographic assay (Wang, Xie, et al, 2017) has been reported. However, most of the reported assays were developed for food samples.…”