Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is a virus that causes COVID-19 disease. In this research, SARS-CoV-2 spike glycoprotein was selected as a template for the development of an electrochemical sensor based on the molecularly imprinted polymer.
The general molecular imprinting process consists of chemical or electrochemical polymerization from a mixture containing functional monomers and template molecules. The polymerisation step is then followed by the removal of the template, which generates the binding sites in the structure of the polymer, which are specific or complementary to the template molecules [1]. This characteristic can be used in the development of sensors for detecting both biological and chemical molecules [2].
In this study, the SARS-CoV-2 spike glycoprotein imprinted polypyrrole-based (MIP-Ppy) sensor was developed [3]. The pre-polymeric mixture contained 0.5 M pyrrole as a monomer and 50 µg/mL of SARS-CoV-2 spike glycoprotein as a template in PBS solution, pH 7.4. The polymeric layer was deposited electrochemically onto the surface of a platinum electrode by a sequence of potential pulses. The template molecules were extracted by washing the polymer in 0.05 M H2SO4 solution for 10 min. In comparison, an electrode was modified with a non-imprinted polypyrrole layer (NIP-Ppy). The properties of both MIP-Ppy and NIP-Ppy were evaluated by pulsed amperometric detection. The interaction between SARS-CoV-2 spike glycoproteins and MIP-Ppy was assessed by the Anson plot-based calculations.
The obtained results prove that SARS-CoV-2 glycoprotein interaction is stronger with MIP-Ppy film than with NIP-Ppy film.