Optimization of Gold Nanoparticle for Anti-Vibrio cholerae Aptasensor Design

Accurate identification and quantification of foodborne pathogens from environmental and clinical samples require techniques with high sensitivity and specificity. Additionally, Vibrio cholerae is prevalent among humans and animals and can harm individuals. The purpose of this research is to optimize Gold NanoParticles (GNPs) for nano bio probe design using an anti-V. cholerae aptamer selected by in silico tools. For this, a library of new aptamer sequences for detecting V. cholerae with higher sensitivity and specificity was designed. Then, using bioinformatics tools and molecular docking, the binding aptamers to the surface protein of V. cholerae (OmpU) were examined. The sequences Apt-Ch30 were proposed as final candidates for constructing the V. cholerae diagnostic aptasensor. The correlation between the volume fraction of GNPs and NaCl concentration was investigated using Design Expert software with the Response Surface Method (RSM). The results indicate that this model not only helps determine optimal process variable conditions but also accurately examines process variable interactions. The magnitude of R2 confirms satisfactory compliance of experimental data with the second-order model. The optimal conditions of the process were the volume fraction of GNPs 90% (v/v) and the concentration of NaCl 14 mM. The chosen aptamer sequence was meticulously synthesized and employed to functionalize the surface of the Gold Nanoparticle (GNP). The effectiveness of the optimized aptasensor for detecting bacteria was evaluated by monitoring the aggregation or dispersion of the GNPs in the presence of sodium chloride (NaCl). Finally, a high-sensitivity aptasensor was designed for more precise and rapid detection of V. cholerae.