Low-cost, disposable sensors based on polystyrene waste and V–TiO2 microneedle composites for diagnosis of renal malfunction and muscle dystrophy

Abstract

A compact, cost-efficient, and disposable electrochemical creatinine sensor is designed using disposable screen-printed carbon electrodes coated with a composite receptor based on polystyrene foam (i.e., packaging material waste) and anatase-phase V–TiO2 microneedles. The electrochemical sensor is capable of monitoring 1–25 μM creatinine in a standard redox solution at 7.4 pH and room temperature. The electrochemical measurements are performed with a portable potentiostat using an android smartphone. Cyclic voltammetry and differential pulse voltammetry characteristics are measured to monitor the concentration of creatinine. The sensor exhibits excellent creatinine sensitivity of 30.95 ± 1.73 μA/cm2⸳μM and an extremely low threshold detection limit of 184 nM creatinine.