One-Step Electrochemical Modification of PEDOT:PSS/PBNPs Hybrid Hydrogel on the Screen-Printed Electrode Surface for Highly Sensitive Detection of Creatinine

Creatinine (CRE) is frequently measured in clinical practice due to its recognized significance as a pivotal biomarker across a spectrum of renal and cardiovascular disorders. However, the rapid and accurate detection of CRE for assessing kidney and muscle functions remains challenging. Here, we prepared the poly(3,4ethylenedioxythiophene):poly(styrenesulfonate) (PEDOT:PSS) hydrogel uniformly loaded with Prussian blue nanoparticles (PBNPs) via a one-step metal-assisted electrochemical modification method on the screen-printed electrode for ultrasensitive CRE detection. The conductive, porous PEDOT:PSS/PBNPs hydrogel provided a confined space that facilitated highly efficient biocatalytic cascade reactions of creatinine amidohydrolase, creatine amidinohydrolase (Cl), and sarcosine oxidase, enabling the CRE detection with a high sensitivity (40.2 μA mM