title: Rapid concentration detection and differentiation of bacteria in skimmed milk using surface enhanced Raman scattering mapping on 4-mercaptophenylboronic acid functionalized silver dendrites.
abstract: A novel method was developed to rapidly concentrate, detect, and differentiate bacteria in skimmed milk using surface enhanced Raman scattering (SERS) mapping on 4-mercaptophenylboronic acid (4-MPBA) functionalized silver (Ag) dendrites. The 4-MPBA 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 84.92 ± 3.25% at 106CFU/mL and as high as 99.65 ± 3.58% at 103CFU/mL. Four different strains, two gram-negative and two gram-positive, 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 103CFU/mL bacterial cells in 50 mM NH4HCO3solution and 102CFU/mL cells in both 1% casein and skimmed milk. Our results demonstrate the feasibility of using SERS mapping method coupled with 4-MPBA functionalized Ag dendrites for rapid and sensitive bacteria detection in complex liquid samples. Graphical Abstract A novel SERS mapping method based on 4-mercaptophenylboronic acid functionalized silver (Ag) dendrites was developed to rapidly concentrate, detect, and differentiate bacteria.
authors.affiliation: Department of Food Science, University of Massachusetts, Amherst, MA, 01003, USA.|College of Food Science and Engineering, Northwest A&F University, Yangling, Shaanxi, 712100, China.
authors.forename: Panxue
authors.initials: P
authors.lastname: Wang
authors.affiliation: Department of Food Science, University of Massachusetts, Amherst, MA, 01003, USA.
authors.forename: Shintaro
authors.initials: S
authors.lastname: Pang
authors.affiliation: Department of Food Science, University of Massachusetts, Amherst, MA, 01003, USA.
authors.forename: Brooke
authors.initials: B
authors.lastname: Pearson
authors.affiliation: Department of Food Science, University of Massachusetts, Amherst, MA, 01003, USA.
authors.forename: Yayoi
authors.initials: Y
authors.lastname: Chujo
authors.affiliation: Department of Food Science, University of Massachusetts, Amherst, MA, 01003, USA.
authors.forename: Lynne
authors.initials: L
authors.lastname: McLandsborough
authors.affiliation: College of Food Science and Engineering, Northwest A&F University, Yangling, Shaanxi, 712100, China.
authors.forename: Mingtao
authors.initials: M
authors.lastname: Fan
authors.affiliation: Department of Food Science, University of Massachusetts, Amherst, MA, 01003, USA. lilihe@foodsci.umass.edu.
authors.forename: Lili
authors.initials: L
authors.lastname: He
mesh_terms: D000818:Animals; D001419:Bacteria / Q000145:classification / Q000302:isolation & purification*; D001897:Boronic Acids / Q000737:chemistry*; D057230:Limit of Detection; D008892:Milk / Q000382:microbiology*; D015203:Reproducibility of Results; D012834:Silver / Q000737:chemistry*; D013059:Spectrum Analysis, Raman / Q000379:methods*; D013438:Sulfhydryl Compounds / Q000737:chemistry*
chemical_list: C510906:4-mercaptophenylboronic acid; D001897:Boronic Acids; D013438:Sulfhydryl Compounds; D012834:Silver
keywords: 4-Mercaptophenylboronic acid; Bacteria; SERS mapping; Salmonella; Silver dendrites