Imprinted Polymers as Synthetic Receptors in Sensors for Food Safety

Abstract

Foodborne illnesses represent high costs worldwide in terms of medical care and productivity. To ensure safety along the food chain, technologies that help to monitor and improve food preservation have emerged in a multidisciplinary context. These technologies focus on the detection and/or removal of either biological (e.g., bacteria, virus, etc.) or chemical (e.g., drugs and pesticides) safety hazards. Imprinted polymers are synthetic receptors able of recognizing both chemical and biological contaminants. While numerous reviews have focused on the use of these robust materials in extraction and separation applications, little bibliography summarizes the research that has been performed on their coupling to sensing platforms for food safety. The aim of this work is therefore to fill this gap and highlight the multidisciplinary aspects involved in the application of imprinting technology in the whole value chain ranging from IP preparation to integrated sensor systems for the specific recognition and quantification of chemical and microbiological contaminants in food samples.

Keywords: biomimetic sensor; food safety; imprinted polymers.

Figure 1

Synthetic steps to prepare MIPs.

Figure 2

Synthetic steps to prepare SIPs: (i) self-assembly method; (ii) molding technique; (iii) miniemulsion polymerization; and (iv) stamping technique.

Figure 3

Schematic representation of synthesis of imprinted polymer on magnetic nanoparticles surface. TEM images of: (i) functionalized nanoparticles; and (ii) imprinted polymer magnetic nanoparticles. Reprinted from [187]. Copyright (2016), with permission from Elsevier.

Figure 4

Scanning electron microcopy (SEM) images of (i) non-Imprinted particle and (ii) imprinted particle; and corresponding magnified images of (iii) non-imprinted and (iv) imprinted beads. Figure adapted from [197] with permission under open-access copyright agreement.

Figure 5

Schematic representation of polypyrrole imprinting with bacteria. SEM images of: (i) imprinted polypyrrole; and (ii) polypyrrole film with bacteria cavities. Reprinted (adapted) with permission from [80]. Copyright (2013) American Chemical Society.

Figure 6

Schematic representation of the preparation of Hepatitis A-imprinted poly(dopamine). Reprinted from [201]. Copyright (2017), with permission from Elsevier.

Figure 7

Imprinted polymers coupling to transducers for food safety application.

Figure 8

Electrochemical detection of Escherichia coli: (i,ii) SEM images of bacteria imprinted electrodes; and (iii) calibration curve obtained from the capacitive response of the electrode towards the analyte. Reprinted from [209]. Copyright (2017), with permission from Elsevier.

Figure 9

QCM detection of tobramycin using a molecularly imprinted polymer: (i) AFM image of MIP film. (ii) The effect of concentration on QCM response of target: (1) adsorption; (2) desorption; and (3) regeneration. Reprinted from [222]. Copyright (2014), with permission from Elsevier.