In this study, it has been demonstrated that the antibody/
AuNP/MNP nanocomposites, with their high capture capacity, can
be employed as a highly sensitive and specific tool for the
S. aureus sensing. In only 40 min, the target cells in the pure
sample could be detected with the LOD of 1.5 103 CFU while as
low as 1.5 105 CFU of S. aureus in the milk sample could be
distinguished from the negative control. The efficacy of these
nanocomposites stems from the utilization of the properties of
both the MNPs and the AuNPs that are used as the platforms for
the magnetic separation and the signal generation respectively.
Our novel approach provides a simple and convenient process for
synthesizing the antibody/AuNP/MNP nanocomposites that maintain
high dispersion stability and effective particle concentration.
The antibody/AuNP/MNPs-based colorimetric sensor can offer
many advantages such as the ease of operation, high sensitivity
and specificity as well as the quick response time, all of which
make it an attractive method for various pathogen detections.