Hemin-Functionalized Microfluidic Chip with Dual-Electric Signal Outputs for Accurate Determination of Uric Acid
Peng Zhao, Yiyi Liu, Yuanyuan Chen, Mei Yang, Shixian Zhao, Na Qi, Yongzhong Wang, Danqun Huo, Changjun Hou
Abstract
Herein, we develop a hemin-functionalized microfluidic chip with dual-electric signal outputs for accurate determination of uric acid (UA). Hemin is designed as the catalyst, which could trigger a built-in reference signal. Carbon nanotube (CNT) and alkalinized titanium carbide (alk-Ti3C2Tx) are used as attachment substrates to strengthen the signal. Benefiting from the synergistic action of hemin, CNT, and alk-Ti3C2Tx, the hybrid functionalized sensor shows prominent electrochemical capacity, desirable catalytic activity, and unique built-in signal ability. Through density functional theory calculations, the structure–reactivity relationship and possible signal output mechanism are deeply investigated. The functionalized sensor is further integrated into a microfluidic chip to prepare a portable electrochemical sensing platform, in which multiple sample processing steps including primary filtration, target enrichment, and reliable analysis can be conducted step-by-step. Based on the abovementioned designs, the developed functionalized microfluidic platform presents desirable performance in UA determination with a detection limit of 0.41 μM. Furthermore, it is capable of accurately detecting UA in urine samples, providing a promising idea for biomolecule monitoring.