A new multifunctional copper iodide–pyrazine hybrid for sensitive creatinine detection in biological samples: synthesis, structural features, characterization, and electrochemical evaluation

Abstract

The organic–inorganic hybrid compound [Cu₂I₂(μ-pyrazine)] was synthesized via a hydrothermal method and characterized using X-ray diffraction (XRD), infrared (IR) and Raman, UV–visible, and X-ray photoelectron (XPS) techniques. The compound crystallizes in a triclinic system and forms a 2D staircase-like framework. Optical measurements indicate a direct bandgap of 0.95 eV, suggesting semiconducting behavior and potential applicability as a biological sensor. Furthermore, electrodes modified with [Cu₂I₂(μ-pyrazine)] were evaluated for creatinine detection, exhibiting high sensitivity and selectivity, with a detection limit as low as 1 × 10⁻⁸ M. The sensor also demonstrated excellent stability and reproducibility in real sample analyses, achieving recovery rates between 90.3% and 103.9%. These findings highlight the multifunctionality and potential of this hybrid material for applications in both clinical diagnostics and environmental monitoring.