Exploration of molecularly imprinted polymer (MIP) nanohybrid films as DNA sensors for the detection of porcine

In the present study, novel molecularly imprinted polymer (MIP) nanocomposite films were prepared for the detection of porcine double-stranded deoxyribonucleic acid (dsDNA) in food samples. A fragment of dsDNA from the pork mitochondrial genome was chosen as a template molecule for porcine identification. The molecularly imprinted polymer (MIP) nanocomposite films of polypyrrole-TiO2 (PPy/TiO2) were synthesized electrochemically on the surface of indium-tin-oxide (ITO) glass electrode. A strong voltammetric (DPV) response was observed for capturing dsDNA from the samples containing porcine. The batch rebinding experiments revealed that PPy/TiO2 MIP possessed excellent binding capacity (Q = 87.44%) and a high imprint factor (2.30) than non-imprinted polymers (NIPs). The selectivity experiments indicated that MIP had excellent recognition selectivity for porcine dsDNA. MIP exhibited higher relative selectivity coefficient (K ' = 4.26 mu M/mu L) toward porcine dsDNA as compared to structural analogue beef dsDNA (K ' = 0.23 mu M/mu L) and chicken dsDNA (K ' = 0.21 mu M/mu L). This could be attributed to the introduction of the imprinted cavities exactly matching the porcine dsDNA on the surface of MIP nanocomposite film. Furthermore, PPy/TiO2 MIP showed a high reusability and low LOD (2.06 mu M) and LOQ (6.89 mu M) values.