Novel Methods for Fumonisins B1 Detection Based on AuNPs Labeling and Aptamer Recognition

Abstract:

This work set up a new naked eye detection method for FB1 abased on the high identification function of DNA aptamer and the color changing effect of AuNPs.This assay method taked AuNPs as carrier and firstly linked to DNA1 and then assembled FB1-aptamer-DNA1-AuNPs complex throuth the hybridzation process between FB1-aptamer and DNA1-AuNPs.When added different concentrations of FB1,FB1-aptamer prefered to connect to FB1 and then subsequently additional DNA2 chain that matched with DNA 1 chain can hybrid with exposed DNA1 resulting in AuNPs aggregation.Thus the color changes from red to purple and blue could be observed by the naked eye.Optimal conditions avoided to much salt induced AuNPs aggregation caused error effectively.Furthermore,we added SDS in DNA1 or DNA2 chain connected to AuNPs to maintain the color of AuNPs and improved the concentration of NaCl to 500 mmol/L and DNA loading enlarge 3 times.This breaks the traditional boundary of 100 mmol/L NaCl can caused the color change of AuNPs.The linear range of the colorimetric aptasensor covers a large variation of FB 1 concentration from 125 ng/L to 1500 ng/L and the detection limit of 125 ng/L is obtained.