Location: Quality & Safety Assessment Research2013 Annual Report
1a. Objectives (from AD-416):
To develop a nanobiosensor to detect Salmonella using surface-enhanced Raman scattering (SERS) technique: 1) determine SERS characteristics of Salmonella; 2) develop chemometric models to differentiate Salmonella from other bacteria; 3) classify different Salmonella strains; and 4) evaluate detection limits of nanobiosensor.
1b. Approach (from AD-416):
We will develop methodologies to test and validate the SERS techniques. A series of experiments will be conducted based on the following methods: 1) Design, fabricate SERS substrate to optimize for lower detection limits; 2) Salmonella sample preparation; 3) SERS measurement; 4) Test and validate classification models for different serotypes; 4) Test detectability from different background flora.
3. Progress Report:
This research relates to inhouse objective 1. Develop methods and instruments to identify food safety hazards throughout various stages of poultry and egg production and processing. The protocol for aptamer-based nanobiosensor for specific detection of Salmonella Typhimurium (ST) from food matrix was developed using surface enhanced Raman scattering (SERS) with modified silver nanorod array (AgNR) substrates. Aptamers were immobilized on AgNR substrates followed by immobilization of spacer molecules on AgNR. SERS spectral signatures were obtained from ST cells bound to aptamer-modified SERS substrate. This method improved specificity of nanobiosensor for foodborne pathogen detection.