Detection of amoxicillin residues in egg extract with a molecularly imprinted polymer on gold microchip using surface plasmon resonance and quartz crystal microbalance methods

Abstract

In this study, surface plasmon resonance (SPR) and quartz crystal microbalance (QCM) sensors were prepared for the detection of amoxicillin from the commercial and local chicken eggs by using molecular imprinting technique. Amoxicillin imprinted poly(hydroxyethyl methacrylate-methacrylic acid) polymeric film was synthesized onto the surface of the SPR and QCM chips by ultra violet polymerization to determine lower concentrations of amoxicillin. Ellipsometry, contact angle analysis, and atomic force microscopy measurements were used for the surface morphology of the polymeric film layer. The ellipsometric thickness of AMOX imprinted and nonimprinted SPR and QCM chip surfaces were measured as 35 ± 0.9 nm, 32.89 ± 1.9 nm, 30 ± 0.6 nm, and 28 ± 0.22 nm, respectively. Contact angles of bare gold surfaces, AMOX imprinted SPR and QCM chip surfaces were measured to be as 82.3°± 0.15, 79.2°± 0.14, 75.01°± 1.07, and 69.11°± 0.89, respectively. The range of linearity was measured as 0.1 to 10 ng/mL for amoxicillin imprinted SPR and QCM sensors. The maximum residue limit of AMOX in eggs is at 10 μg/kg in accordance with the "Positive List System for Agricultural Chemical Residues in Foods." The response time for the test, including adsorption, desorption, and regeneration, was approximately 45 min. The limit of detections for SPR and QCM sensors were found to be 0.0005 and 0.0023 ng/mL, respectively. The reusabilities of amoxicillin imprinted SPR and QCM sensors were observed by the equilibration-binding-regeneration. Validation studies of the AMOX imprinted SPR and QCM sensors were performed by liquid chromatography-tandem mass spectrometry.

Patulin Imprinted Nanoparticles Decorated Surface Plasmon Resonance Chips for Patulin Detection

“…Selectivity (k) and relative selectivity (k') coefficients were calculated according to kinetic analysis of the patulin imprinted and the non-imprinted SPR nanosensors. k and k' are described by the following equations [34]:…”

“…The limit of detection (LOD = 3.3 S/m) and quantification (LOQ = 10 S/m) of patulin molecules were calculated based on the slope of the calibration curve and with y=0.127 8x+0.125 equation. S and m are the standard deviations of the intercept and slope of the regression line, respectively [34]. The LOD and LOQ for patulin detection were 0.011 nmolar and 0.036 nmolar, respectively.…”

“…As the validity of the SPR nanosensor technology in food analysis increases, the number of studies on target analyte determination in this field also increases. The targeted analytes in this area are pathogens, toxins, vitamins, hormones, allergens, proteins, and chemical contaminants [32][33][34][35][36].…”

Preparation of Molecularly Imprinted Optical Sensors for The Real Time Detection of Phenol

“…The most important feature of molecular imprinting is the formation of cavities belonging to the template mo-lecule on the polymer surface [45]. The catechol molecule was used as a competitive agent to examine the selectivity of phenol imprinted SPR sensor (Figure 6).…”

“…Catechol solution at a concentration of 5 nM was prepared and kinetic analyzes were performed with phenol imprinted and non-imprinted SPR sensors. The selectivity (k) and the relative selectivity (k') coefficients were calculated using the obtained kinetic data[45].…”