Electrochemically deposited Au nano-island on laser-scribed graphene substrates as EC-SERS biochips for uremic toxins detection

Background: Chronic kidney disease (CKD) leads to uremic toxin buildup, requiring early detection for better management. Existing methods lack sensitivity, speed, or affordability for point-of-care diagnosis. This work addresses this by creating a novel sensor for rapid, sensitive uremic toxin detection. Methods: The sensor leverages the combined effects of surface-enhanced Raman scattering (SERS) and electrochemistry (EC) for superior detection. The LIG substrate provides a stable platform for AuNPs, facilitating interaction with target molecules. Additionally, electrochemical deposition optimizes the sensor's sensitivity by amplifying the local electromagnetic field around AuNPs and offering specific binding sites for uremic toxins. Significant findings: The developed sensor demonstrates exceptional performance in detecting uremic toxins. It achieves remarkably low detection limits (10^-3 M for creatinine/uric acid, 10^-4 M for urea) and offers distinct, concentration-dependent responses for different toxins in cyclic voltammetry (CV) measurements. Furthermore, characteristic oxidation peaks at specific potentials allow for direct identification and quantification of the toxins. These findings highlight the immense potential of this cost-effective and scalable sensor for point-of-care diagnostics and remote monitoring of kidney function. This advancement can significantly improve patient care by facilitating early detection of kidney problems and enabling timely intervention.