A novel electrochemical microfluidic separation and sensing (EMSS) device was fabricated for monitoring neurotransmitters (NTs) in human blood plasma. Initially, the neurotransmitter separation was achieved with the AC field perturbation in a microfluidic channel followed by the successive detection using a sensor at the end of channel. The sensor performances using some of electron transfer mediators were demonstrated for sensing of seven NTs (5-hydroxytryptamine, dopamine, norepinephrine, epinephrine, 5-hydroxyindoleacetic acid, 5-hydroxytryptophan, and 3, 4-dihydroxy-l-phenylalanine). The sensor probe was fabricated by electropolymerization of 2, 2´:5´, 5″-terthiophene-3´-p-benzoic acid (TBA) with heteroatoms (N and S) doped porous carbon (HPC) to form a composite layer onto the screen printed carbon electrode, followed by covalent immobilization of a redox mediator. Among the tested mediators, Evans blue revealed the most superior performance. The parameters affecting the sensing performance were optimized, in terms of pH, temperature, fluid flow rate and AC parameters (i.e., frequency, amplitude, etc). The calibration plots for the seven NTs standard samples were found to be linear within the range of 0.05-130 nM with the detection limits between 0.034 (±0.005) and 0.044 (±0.004) nM. Finally, the reliability of the proposed device was assessed by detecting six NTs and two NTs derivatives in a human plasma sample.

新型电化学微流分离和传感（EMSS）装置被用来监测人类血浆中的神经递质（NTs）。最初，神经递质的分离是通过微流体通道中的AC场扰动实现的，然后使用通道末端的传感器进行连续检测。证明了使用某些电子转移介质的传感器性能可检测七个NT（5-羟基色胺，多巴胺，去甲肾上腺素，肾上腺素，5-羟基吲哚乙酸，5-羟基色氨酸和3,4-二羟基-1-苯丙氨酸）。传感器探头是通过2、2′：5′，5′′-terthiophene-3′- p的电聚合制成的带有杂原子（N和S）的-苯甲酸（TBA）掺杂多孔碳（HPC），以在丝网印刷的碳电极上形成复合层，然后共价固定氧化还原介体。在经过测试的调解员中，Evans blue表现出最出色的表现。在pH值，温度，流体流速和AC参数（即频率，幅度等）方面优化了影响传感性能的参数。发现七个NTs标准样品的校准图在0.05-130 nM范围内是线性的，检出限在0.034（±0.005）和0.044（±0.004）nM之间。最后，通过检测人体血浆样品中的六个NT和两个NTs衍生物来评估所提出设备的可靠性。