Plasmonic ELISA based on DNA-directed gold nanoparticle growth for Cronobacter detection in powdered infant formula samples

Abstract

The traditional gold nanoparticle (AuNP) growthbased plasmonic ELISA (pELISA) strictly and directly controlled by reducing reagents can achieve high sensitivity, but it remains fragile toward the surrounding environment. This work developed a sandwich pELISA for Cronobacter detection in powdered infant formula samples by mediating AuNP growth through DNA. In this assay, DNA adsorbed on the surface of gold nanoseeds guided the anisotropic crystal growth with hydroxylamine as a reducing reagent, and the catalase-hydrogen peroxide (Cat-H 2 O 2) system was introduced to bridge the DNA-directed AuNP growth and pELISA, as such DNA can be cleaved into fragments by the hydroxyl radical generated from oxidation of H 2 O 2 through Fenton reagents. Under optimized conditions, the proposed pELISA can qualitatively detect Cronobacter species (Cronobacter muytjensii ATCC 51329) by the naked eye with a cutoff limit of 3 × 10 5 cfu/ mL. This method also revealed a good linear range (3 × 10 2 to 3 × 10 7 cfu/mL) for quantitative detection of C. muytjensii ATCC 51329 with a limit of detection of 1.6 × 10 2 cfu/mL, which is approximately 162.5 times lower than that of horseradish peroxidase-based conventional ELISA (2.6 × 10 4 cfu/mL). By taking advantage of highly stable DNA-directed AuNP growth, the proposed method shows a good performance in powdered infant formula samples spiked with different concentrations of C. muytjensii ATCC 51329 with average recoveries ranging from 90.79 to 119.09% and coefficient of variation ranging from 4.24 to 9.55%. These values corresponded to an acceptable accuracy and precision for the proposed method. In brief, this work shows potential for screening other analytes in food safety, clinical diagnostics, and environmental monitoring.

Development of a Gold Nanoparticle-Based ELISA for Detection of PCV2

“…A visual change in ELISA coloration with varying concentrations of AuNPs was also observed in the work of Wu et al (2019), who developed a sandwich pELISA for Cronobacter detection in powdered infant formula samples, with a cutoff limit of 3 × 10 5 cfu/mL [ 30 ].…”

“…A visual change in ELISA coloration with varying concentrations of AuNPs was also observed in the work of Wu et al (2019), who developed a sandwich pELISA for Cronobacter detection in powdered infant formula samples, with a cutoff limit of 3 × 10 5 cfu/mL [30]. An analysis of the results revealed that when the sample was negative, it exhibited a red hue and higher absorbance than did the positive samples, which showed a purple tint.…”

Shape dependent sensing potential of gold nanoparticles in etching based multicolorimetric plasmonic-ELISA

“…[50][51][52][53][54] In addition, compared to the other reported nanoparticle-based ELISA sensing strategies, the developed method provides several other advantages including (i) easy integration with conventional ELISA schemes, wherein HRPlabeled detector antibodies are used, [55][56] (ii) elimination of false positive and negative signal due to autoaggregation of the nanoparticles, [57][58] (iii) the greater stability of the AuNRs towards temperature, light and the biological thiols as compared to silver nanoprisms, 59 and (iv) easy and simple as it does not require any conjugation or surface functionalization of the AuNRs. [60][61]…”

Electrochemical Detection of ompA Gene of C. sakazakii Based on Glucose-Oxidase-Mimicking Nanotags of Gold-Nanoparticles-Doped Copper Metal-organic Frameworks

“…The bacterial culture method for C. sakazakii is a traditional method that takes 5 to 7 days to obtain results and cannot meet the needs for rapid detection and screening of bacteria. Some other methods that are classified into protein-based biosensing method [5][6][7] and DNA-based biosensing method [8][9][10][11][12][13][14][15][16] have been promoted and applied in the detection of C. sakazakii. Protein-based immunoassays, such as enzyme-linked immunosorbent assays (ELISAs) [5] and lateral flow immunoassays [6], are based on antibody-antigen interactions, which require a certain concentration of targets in samples, and sometimes cannot be applied in the detection at an early infection stage.…”

“…Some other methods that are classified into protein-based biosensing method [5][6][7] and DNA-based biosensing method [8][9][10][11][12][13][14][15][16] have been promoted and applied in the detection of C. sakazakii. Protein-based immunoassays, such as enzyme-linked immunosorbent assays (ELISAs) [5] and lateral flow immunoassays [6], are based on antibody-antigen interactions, which require a certain concentration of targets in samples, and sometimes cannot be applied in the detection at an early infection stage. DNA-based methods including polymerase chain reaction (PCR)-based biosensing methods [8,9], fluorescence biosensing Sensors 2023, 23, 4396 2 of 14 methods [10,11], colorimetric biosensing methods [12,13], and electrochemical biosensing methods [14][15][16] have been intensively promoted and investigated for the detection of C. sakazakii.…”