Design and development of aptamer-gold nanopartiele for colorimetric detection of methylphosphonic acid

Response surface methodology (RSM) based on face-centered central composite design (FCCCD) was applied to optimize the methylphosphonic acid (MPA) detection using DNA aptamer-citrate capped-gold nanoparticles (DNA aptamer-cit-AuNPs). Images of the color change of the solution were captured and further processed to red (R), green (G) and blue (B) values. Three parameters: cit-AuNPs concentration (Xi) , DNA aptamer concentration (X2) and incubation period (X3) were investigated. Analysis of variance (ANOVA) was used to determine the significant factors affecting the detection. Both predicted and experimental responses show good agreement at 95% confidence level. Hence, this method could be implemented for on-site MP A detection.