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Developing low-cost and multiplexing electrochemical (EC) devices for bioassay is imperative. Herein, a polymer-based EC device, named EC 6-well plate, was proposed and fabricated using a non-photolithography method. Polyethylene terephthalate glycol (PETG) was used as a substrate and laser-cut polyester (PET) film was used as a mask for patterning the electrodes. The diameter of the working electrode (WE) was 900 μ m, and each WE-modifying step only requires 1 μ l of reagent. Acrylic mold with wells (60 μ l) was bonded to the PETG substrate. Miniaturization of reference electrodes (RE) was discussed. The solid-state Ag/AgCl RE-based three-electrode system, the Au three-electrode system (3E), and Au two-electrode system (2E) were prepared and employed to develop an immunosensor for toxin B detection. Differential pulse voltammetry (DPV) and electrochemical impedance spectroscopy (EIS) were applied to test the stability of the EC immunosensor. The solid-state Ag/AgCl RE-based system showed a standard deviation of open circuit potential (OCP) of 4.6 mV. The 3E system and 2E system showed the standard deviations of OCP of 0.0026 mV and 0.32 mV, respectively. It revealed that the EC 6-well plate with the 3E system is excellent for developing an EC immunosensor. 

Owing to their merits of simple, fast, sensitive, and low cost, electrochemical biosensors have been widely used for the diagnosis of infectious diseases. As a critical element, the receptor determines the selectivity, stability, and accuracy of the electrochemical biosensors. Molecularly imprinted polymers (MIPs) and surface imprinted polymers (SIPs) have great potential to be robust artificial receptors. Therefore, extensive studies have been reported to develop MIPs/SIPs for the detection of infectious diseases with high selectivity and reliability. In this review, we discuss mechanisms of recognition events between imprinted polymers with different biomarkers, such as signaling molecules, microbial toxins, viruses, and bacterial and fungal cells. Then, various preparation methods of MIPs/SIPs for electrochemical biosensors are summarized. Especially, the methods of electropolymerization and micro-contact imprinting are emphasized. Furthermore, applications of MIPs/SIPs based electrochemical biosensors for infectious disease detection are highlighted. At last, challenges and perspectives are discussed.