In this study, a biosensor with a dual recognition system comprising a molecularly imprinted polymer (MIP) and aptamers selective for lincomycin was fabricated. The MIP was synthesized by electropolymerization of carbon dots (C-dots)-tagged DNA aptamers combined with lincomycin and o-aminophenol on the gold-nanoparticle-functionalized graphene oxide (Au-GO)-modified electrode. Electrogenerated chemiluminescence (ECL) resonance energy transfer was observed between Au-GO and C-dots. After the C-dots accepted the energy, they acted as a signal indicator and exhibited enhanced signal intensity in the presence of target lincomycin. When lincomycin was competitively bound to DNA aptamers and MIP, it blocked the transfer of energy, and a decreased ECL signal was observed. Hence, a dual recognition method for the detection of lincomycin is realized. Using this strategy, the sensor exhibited a linear ECL response to lincomycin at concentrations from 5.0 × 10 -12 mol/L to 1.0 × 10 -9 mol/L. The detection limit of this assay was found to be 1.6 × 10 -13 mol/L. This method was utilized to determine lincomycin residuals in meat samples with satisfactory results.
Keywords: Aptamer; Dual recognition; Energy transfer; Molecularly imprinted; lincomycin.
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