An ultrasensitive sandwich immunoassay with a glucometer readout for portable and quantitative detection of Cronobacter sakazakii

作者：Ye, Lingxian; Zhao, Guangying^*; Dou, Wenchao^*

来源：Analytical Methods, 2017, 9(44): 6286-6292.

DOI：10.1039/c7ay02222k

• POWDERED INFANT FORMULA
• PERSONAL GLUCOSE METERS
• ENTEROBACTER-SAKAZAKII
• RAPID DETECTION
• SPP.
• NANOPARTICLES
• ANTIBODIES
• TARGETS
• ASSAY
• PCR

Developing portable and low-cost methods for quantitative detection of Cronobacter sakazakii (C. sakazakii) from powdered infant formula plays a significant role in controlling and preventing a range of serious neonatal infections. Here, we reported a novel methodology for C. sakazakii detection using a low-cost, simple, and widely accessible personal glucose meter (PGM) as the readout. The electrochemical immunoassay strategy was based on antibody and glucose oxidase coated silica nanoparticles (SiNP-GOX-IgG) and antibody functionalized silica-coated magnetic nanoparticles (MNP-IgG). In the process of detecting a positive sample, a sandwich immunocomplex was formed between the MNP-IgG, C. sakazakii and SiNP-GOX-IgG. Then, the above sandwich composites were dispersed in glucose solution, and the concentration of glucose was measured using the PGM. Under optimal conditions, a linear relationship between the decrease of glucose concentration and the logarithm of C. sakazakii concentration was obtained in the concentration range from 9.0 x 10(2) to 9.0 x 10(7) CFU mL(-1) with a detection limit of 4.2 x 10(1) CFU mL(-1) (S/N = 3). This simple immunoassay holds great potential as an efficient, sensitive and selective point-of-care testing (POCT) tool for C. sakazakii detection.

• 出版日期2017-11-28
• 单位浙江工商大学