Authors: Panxue Wang Shintaro Pang Brooke Pearson Yayoi Chujo Lynne McLandsborough Mingtao Fan Lili He
Publish Date: 2017/01/14
Volume: 409, Issue: 8, Pages: 2229-2238
Abstract
A novel method was developed to rapidly concentrate detect and differentiate bacteria in skimmed milk using surface enhanced Raman scattering SERS mapping on 4mercaptophenylboronic acid 4MPBA functionalized silver Ag dendrites The 4MPBA functionalized Ag dendritic SERS substrate was used to capture the bacterial cells and enhance the bacterial signal Salmonella a significantly important food pathogen was used as the representative strain to optimize and evaluate the developed method The capture efficiency for Salmonella enterica subsp enterica BAA1045 SE1045 was 8492 ± 325 at 106 CFU/mL and as high as 9965 ± 358 at 103 CFU/mL Four different strains two gramnegative and two grampositive can be clearly distinguished by their SERS spectra using principle component analysis A mapping technique was utilized to automatically collect 400 spectra over an area of 60 μm × 60 μm to construct a visual image for a sensitive and statistically reliable detection within 30 min Using this method we were able to detect as low as 103 CFU/mL bacterial cells in 50 mM NH4HCO3 solution and 102 CFU/mL cells in both 1 casein and skimmed milk Our results demonstrate the feasibility of using SERS mapping method coupled with 4MPBA functionalized Ag dendrites for rapid and sensitive bacteria detection in complex liquid samples
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