Preparation of AgNPs self-assembled solid-phase substrate via seed-mediated growth for rapid identification of...

In this study, we developed a novel and sensitive AgNPs self-assembled solid-phase (AgNPs-SASP) SERS substrate platform using seed-mediated and liquid interface self-assembly methods and applied the platform for the detection of three bacterial spores. Multivariate statistical analysis (HCA and LDA) were employed for identification and categorization of the obtained data. The results illustrated that AgNPs-SASP exhibited high reproducibility and Raman enhancement effect (1.43 × 10⁴). The Raman shift bands of the three bacterial spores ranged from 400 to 1800 cm^-1 demonstrating the difference in reigon and intensity. And the intensities of their Ca²⁺-DPA Raman bands are significantly different. HCA results revealed that the spectra for the three bacterial spores were statistically different while LDA completely differentiated the spectra for the three bacterial spores with 100 % sensitivity and specificity. Overall, the novel SERS platform based on AgNPs-SASP provides an effective tool for food safety risk control and detection.