ABSTRACT
This study proposed a dual-channel Localized Surface Plasmon Resonance (LSPR) biosensing system via optical fibers for colorimetric detection of melamine using gold nanoparticles (AuNPs)-based aptamer. The aptamer which has high affinity and specificity towards melamine is employed to be the recognition element to capture melamine molecules in AuNPs solution. Quantitative analysis of melamine was performed by measuring spectral absorbance ratio of AuNPs-based aptamer. Under optimized conditions, the linear responses with the square values of correlation coefficient of 0.98 and 0.96 are obtained between the absorbance peak ratio A640/A520 (absorbance at 640 nm and 520 nm) and melamine concentration in the range of 0 to 1 μM from channel 1 and channel 2, respectively. The difference of absorbance peak ratio A640/A520 obtained from two channels is less than 0.03 when the solution containing a certain concentration of melamine was placed into both channels.
