No abstract

The goals of this research were to develop a rapid single-walled carbon nanotube (SWCNT)-based biosensor and to employ it to commercial food products for Ara h1 detection. The SWCNT-based biosensor was fabricated with SWCNTs immobilized with antibody (pAb) through hybridization of 1-pyrenebutanoic acid succinimidyl ester (1-PBASE) as a linker. The resistance difference (ΔR) was calculated by measuring linear sweep voltammetry (LSV) using a potentiostat. Resistance values increased as the concentration of Ara h1 increased over the range of 1 to 10 ng/L. The specific binding of anti-Ara h1 pAb to antigen including Ara h1 was confirmed by both indirect ELISA kit and biosensor assay. The biosensor was exposed to extracts prepared from commercial processed food containing peanuts, or no peanuts, and could successfully distinguish the peanut containing foods. In addition, the application of present biosensor approach documented the precise detection of Ara h1 concentrations in commercially available peanut containing foods.

Peanut protein Ara h2 is one of the serious food allergens contributing to the allergic reaction, causing the common reasons for food-related life threating problems over the world. The objective of this study is to develop single-walled carbon nanotubes (SWCNTs) based biosensor using 1-pyrenibutanoic acid succinimidyl ester (1-PBASE) as a linker for rapid detecting peanut allergen Ara h2 in foods. The detection principal of this biosensor was based upon the binding of Ara h2 to the anti-Ara h2 on the linker-modified SWCNTs connecting gold electrode in biosensor silicon template. The measurements of each step were achieved using linear sweep voltammetry (LSV) with a potentiostat for Ara h2 detection. The application of anti-Ara h2 as pAbs on linker immobilized SWCNTs surface increased the sensor resistance values. The developed biosensor showed significant resistance response with the increase in the concentration of Ara h2 from 0 to 1000 ng/mL. Indirect enzyme-linked immunosorbent assay (ELISA) was successfully applied to confirm the specificity of antibodies using 96-well microplates. Scanning electrone microscopy (SEM) confirmed the microstructure of SWCNTs. Sensor sensitivity and specificity were tested with different peanut allergens and the detection range (1-1000 ng/mL).

The objectives of this research were to improve the film-forming properties of Channel Catfish Ictalurus punctatus skin gelatin (CSG) by cross-linking with transglutaminase (TG), determine and optimize the TG reaction time, and characterize the mechanical and barrier properties of CSG edible film. Cross-linking of CSG was performed by TG for 0, 10, 20, 30, and 40 min at 50°C, and the reaction was confirmed by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE). The color and mechanical and barrier properties of edible films fabricated with CSG cross-linked with TG were characterized. Gelatin yields from the extraction ranged from 18.2% to 23.3%. SDS-PAGE exhibited dark bands at 120 and 250 kDa, indicating successful TG-mediated cross-linking. The color of CSG film was not affected by TG cross-linking. The tensile strength of CSG films cross-linked with TG decreased from 42.59 to 21.73 MPa and the percent elongation increased from 42.92% to 76.96% as reaction times increased from 0 to 40 min. There was no significant difference in water vapor permeability of CSG films.