Protocol for low-cost quantification of microplastics through electrochemical impedance spectroscopy from aqueous matrices

We present a protocol to quantify microplastics (MPs) in aqueous matrices by analyzing the solution resistance (R_s) imparted by MPs using electrochemical impedance spectroscopy (EIS). We describe steps for preparing the samples, which can provide accurate MP quantification, and detailed steps for configuring the EIS system. We then detail procedures for constructing calibration curves using R_s as the key parameter and validating this technique using ultraviolet-visible spectroscopy. The protocol supports non-destructive, rapid, and low-cost detection of different MP types.