Popis: |
The suggested work emphasizes the benefits of employing positively charged gold nanoparticles to detect negatively charged E.coli cells by electrostatic attraction without the need of any identification elements. As a result, a simple, label-free colorimetric biosensor for detecting E.coli, a well-known food contaminant, was developed. Initially, the Taguchi approach was used to synthesis small, stable, and positively charged Au NPs in orthogonal array L8 by optimizing 5 critical parameters such as pH, capping agents, temperature, Sonication duration, and Au/LE ratio. Based on the Maximum wavelength (λ max) values and ANOVA, Trail 3 (T3) a Polyallyl amine hydrochloride capped Au NPs (PAH-Au NPs) along with D-Mannose was chosen to be employed in detecting E.coli. It functions as a colorimetric sensor in both sol and paper coated forms. Based on the sensing technique, we discovered that the LOD in sol is (1*105CFU/mL), which is significantly higher than the sensor based on paper (1*102 CFU/mL). |