Surface plasmon resonance detection of ametryn using a molecularly imprinted sensing film prepared by surface-initiated atom transfer radical polymerization

This work aimed to prepare a feasible surface plasmon resonance sensing film by molecular imprinting coupled to immobilized and surface-initiated atom transfer radical polymerization (ATRP) for detection of ametryn. The self-assembly of the functional monomer methacrylic acid around the template ametryn in acetonitrile was studied by UV–Vis spectrophotometric analysis. Based on this study, the tailor-made, highly selective ametryn-imprinted sensing film on a surface plasmon resonance chip was fabricated using MAA as the functional monomer, ethylene glycol dimethacrylate (EGDMA) as the cross-linking monomer. Analysis of surface plasmon resonance (SPR) spectroscopy showed that the imprinted sensing film revealed good imprinting effect and impressive selectivity for ametryn compared to the non-imprinted film. The imprinted SPR sensor exhibited a linear response in the range of 0.1–10 μM (R2 = 0.9985) for detection of ametryn. The selectivity efficiencies of ametryn and other structurally related analogues were 1.0 and 0.10–0.56, respectively. Based on a signal to noise ratio of 3, the detection limits of ametryn were 3.51 × 10−8 M and 6.19 × 10−8 M for the soybean and white rice, respectively. The method showed good recoveries and precision for the soybean and white rice samples spiked with ametryn. This suggests that a combination of SPR sensing with MIP film is a promising alternative method for detection of ametryn.