Development of novel epitope-imprinted polydopamine (PDA) interface for electrochemical detection of gluten in foods | |
| Author | Corpuz, Angelica Revibes |
| Call Number | AIT Thesis no.FB-21-03 |
| Subject(s) | Proteins--Analysis Electrochemistry |
| Note | A thesis submitted in partial fulfillment of the requirements for the degree of Master of Engineering in Food Engineering and Bioprocess Technology, School of Environment, Resources and Development |
| Publisher | Asian Institute of Technology |
| Series Statement | Thesis ; no.FB-21-03 |
| Abstract | The drawbacks of the conventional gluten detection techniques have put biosensors in the spotlight. They can be functionalized to become highly sensitive, selective, simple and cheap detection platforms for gluten-free food testing and verification. In this study, nanomaterial amplification and PDA-based epitope imprinting were applied for voltammetric detection of gliadin, a known pathogenic component of gluten. Critical synthesis and sensing conditions were optimized based on current response while voltammetric response, SEM, Raman spectroscopy and FTIR confirmed the modification. The electrochemical synthesis proved to be effective in depositing conductive RGO film and then imprinted polymeric film on bare SPCE. It was crucial to optimize the thickness of the RGO (10 CV scans) and polymeric (20 CV scans) films, template concentration (0.5 g/L), pre-polymerization time (30 mins), elution time (30 mins), rebinding pH (6.5) and time (10 mins) for a highly sensitive and selective interface. The sensor was able to detect native gliadins in buffered matrix in the linear range of 0.5-15ppm (LOD 0.69, LOQ 2.29) with high selectivity for PQQPFPQQ template (IF=8.68) and gliadin (IF=3.14) and can discriminate against OVA (β=0.15), FA (β=0.25) and casein (β=0.39). It is stable at room temperature for 2 weeks (7.52% RSD), reproducible (2.97% RSD) and reusable (1.64% RSD) once. Negligible matrix effects and reproducible measurements were found in rice flour matrix with higher recovery rates (101.96% and 99.19% for 1.15 and 10 ppm, respectively) than that of ELISA test kit II of Morinaga Institute (82.61% and 83.50%). This suggested the accessibility of epitope on surface of native gliadin and the feasibility of using an acidic template for PDA-based imprinting. The developed technique was able to surpass performance of more sophisticated EG-FET biosensor and a label-free immunoassay demonstrating its robustness. Evaluation of applicability to other toxic prolamins, hydrolyzed or heat-processed gluten sources and other food matrixes were recommended. Finally, certification of the spiking standard material to attest its actual concentration and completion of three data points for proper linear correlation with ELISA is proposed. |
| Year | 2021 |
| Corresponding Series Added Entry | Asian Institute of Technology. Thesis ;no.FB-21-03 |
| Type | Thesis |
| School | School of Environment, Resources, and Development (SERD) |
| Department | Department of Food, Agriculture and Natural Resources (Former title: Department of Food Agriculture, and BioResources (DFAB)) |
| Academic Program/FoS | Food Engineering and Bioprocess Technology (FB) |
| Chairperson(s) | Loc Thai Nguyen;Suwussa Bamrungsap (Co-Chairperson); |
| Examination Committee(s) | Anal, Anil Kumar;Salin, Krishna R.; |
| Scholarship Donor(s) | Asian Development Bank-Japan Scholarship Program (ADB-JSP); |
| Degree | Thesis (M. Eng.) - Asian Institute of Technology, 2021 |