Double difference accumulation SERS strategy for rapid separation and detection of probiotic Bacillus endospores and vegetative cells.

Abstract

Although probiotic Bacillus already has a large-scale market throughout the world, there is a lack of methods for rapid separation and detection of endospores and vegetative cells of probiotic Bacillus. In this study, a "double differential accumulation" SERS strategy was constructed by combining Fe3O4@AgNPs@Van and AuNPs-PA-COFs substrates. While realizing the rapid separation and enrichment of endospores and vegetative cells of probiotic Bacillus, the SERS signals form a "cliff-like" signal difference (10-fold), which was conducive to the rapid differentiation of endospores and vegetative cells. PCA and PLS-DA could completely visualize and classify the endospores and vegetative cells, with detection limits of less than 10 CFU/mL. In food matrix samples, the detection accuracy of "double differential accumulation" SERS strategy for endospores and vegetative cells ranged from 95.45 % to 98.52 %. It can protect the high-density culture of probiotic Bacillus and the safety monitoring of the industrialized production of related products.