A Gold Nanoparticles and MXene Nanocomposite Based Electrochemical Sensor for Point-of-Care Monitoring of Serum Biomarkers
Yongmei Chen, Xinyu Zhang, Yan Liu, Zhengkun Liu, Zijie Li, Zhiqi Li, Xiaman Chen, Jiayi Liu, Zihao Chen, Guangquan Mo, Yong Xia, Lei Mou
Abstract
The development of portable, cost-effective, and highly sensitive biosensors for real-time biomarker detection is crucial for advancing point-of-care testing (POCT) and wearable health monitoring. Here, we present an integrated portable electrochemical sensor (ip-ECS) that combines gold nanoparticles (AuNPs) and MXene-modified screen-printed electrodes (SPEs) with a custom-designed, low-power electronic system for point-of-care monitoring of serum biomarkers. The AuNPs and MXene nanocomposite significantly enhances the electrochemical performance of the SPE by providing a high density of active sites, improved conductivity, and catalytic activity. The detection of two model molecules (DA and UA) validated the feasibility of ip-ECS, achieving detection limits as low as 1.12 and 1.11 μM for UA and DA, respectively. Furthermore, the ip-ECS was successfully applied to detect Cys C in human serum, showing a linear response in the range of 50-5000 ng/mL and a strong correlation (ρ = 0.9556) with conventional latex immunoturbidimetry (LIA). Clinical validation using serum samples from pregnant women revealed elevated Cys C levels in gestational diabetes mellitus (GDM) patients, highlighting the sensor's potential for early GDM risk prediction. The ip-ECS represents a significant step forward in the development of next-generation biosensors for POCT, wearable diagnostics, and personalized medicine.