Paper-Based Electrochemical Biosensors for Food Safety Analysis

Abstract

Nowadays, foodborne pathogens and other food contaminants are among the major contributors to human illnesses and even deaths worldwide. There is a growing need for improvements in food safety globally. However, it is a challenge to detect and identify these harmful analytes in a rapid, sensitive, portable, and user-friendly manner. Recently, researchers have paid attention to the development of paper-based electrochemical biosensors due to their features and promising potential for food safety analysis. The use of paper in electrochemical biosensors offers several advantages such as device miniaturization, low sample consumption, inexpensive mass production, capillary force-driven fluid flow, and capability to store reagents within the pores of the paper substrate. Various paper-based electrochemical biosensors have been developed to enable the detection of foodborne pathogens and other contaminants that pose health hazards to humans. In this review, we discussed several aspects of the biosensors including different device designs (e.g., 2D and 3D devices), fabrication techniques, and electrode modification approaches that are often optimized to generate measurable signals for sensitive detection of analytes. The utilization of different nanomaterials for the modification of electrode surface to improve the detection of analytes via enzyme-, antigen/antibody-, DNA-, aptamer-, and cell-based bioassays is also described. Next, we discussed the current applications of the sensors to detect food contaminants such as foodborne pathogens, pesticides, veterinary drug residues, allergens, and heavy metals. Most of the electrochemical paper analytical devices (e-PADs) reviewed are small and portable, and therefore are suitable for field applications. Lastly, e-PADs are an excellent platform for food safety analysis owing to their user-friendliness, low cost, sensitivity, and a high potential for customization to meet certain analytical needs.

Keywords: biosensor; electrochemical detection; food safety; foodborne pathogens; paper-based device; rapid measurement.

Figure 1

Design of 2D e-PAD biosensor. The 2D designs were adapted from the references: (A) strip [19], and (B) paper disk [47]. Counter electrode (CE), working electrode (WE), and reference electrode (RE).

Figure 2

Examples of e-PADs with 3D design, (A) the pop-up DNA biosensor design and its operation, adapted from [50], and (B) the 3D-origami enzyme biosensors with their measurement steps [14].

Figure 3

Patterning techniques that can be used for e-PAD biosensors, adopted from reference [54]. Open Access under CC BY-NC.

Figure 4

Typical screen-printed electrode (SPE) of e-PADs obtained with the screen-printed technique.

Figure 5

Electrode surface modification approaches of e-PAD biosensors: (a) enzyme-modified electrode; (b) nanostructured layer-modified electrode with biomolecule; (c) electrode modified with redox mediator and biomolecule; (d) electrode modified with redox mediator composite and biomolecule; (e) electrode modified with biomolecule and redox mediator mixture over nanostructured layer, adopted from reference [25]. Open Access under CC BY-NC.

Figure 6

Detection of several food contaminants using e-PADs: (A) An origami device for S. typhimurium detection, adapted from ref [86]. Open Access under CC BY-NC. (B) A flower-like origami device for pesticide detection adapted with permission from ref [38] Copyright 2022 Elsevier. (C) A paper sensor for simultaneous Sn and Pb detection using a portable potentiostat adapted with permission from ref. [89]. Copyright 2022 Elsevier.