AUTHOR=Hou Kaijian , Zhao Pingsen , Chen Yongru , Li Guiping , Lin Yu , Chen Danjie , Zhu Dan , Wu Zezhen , Lian Danchun , Huang Xiaojun , Li Jilin 

TITLE=Rapid Detection of Bifidobacterium bifidum in Feces Sample by Highly Sensitive Quartz Crystal Microbalance Immunosensor

JOURNAL=Frontiers in Chemistry

VOLUME=8

YEAR=2020

URL=https://www.frontiersin.org/journals/chemistry/articles/10.3389/fchem.2020.00548

DOI=10.3389/fchem.2020.00548

ISSN=2296-2646

ABSTRACT=<p>In this work, a quartz crystal microbalance (QCM) sensor has been fabricated using immunoassay for sensitive determination of <italic>Bifidobacterium bifidum</italic>. Au nanoparticle has been used for amplifying sandwich assays. The proposed immunosensor exhibited a linear detection range between 10<sup>3</sup> and 10<sup>5</sup> CFU/mL with a limit of detection of 2.1 × 10<sup>2</sup> CFU/mL. The proposed immunosensor exhibited good selectivity for <italic>B. bifidum</italic> sensing with low cross reactivity for other foodborne pathogens such as <italic>Lactobacillus acidophilus, Listeria monocytogenes</italic>, and <italic>Escherichia coli</italic>. In addition, the proposed immunosensor has been successfully used for <italic>B. bifidum</italic> detection in feces samples and food samples. The frequency decreases of 12, 17, and 10 Hz were observed from the milk samples consisting of the mixtures of <italic>L. acidophilus, L. monocytogenes</italic>, and <italic>E. coli</italic>. The frequency decreases of 8, 15, and 7 Hz were observed from the feces samples consisting of the mixtures of <italic>L. acidophilus, L. monocytogenes</italic>, and <italic>E. coli</italic>.</p>