Huang Kuan-Hsun, Yu Cheng-Xue, Lee Chia-Chun, Tseng Chin-Chung, Fu Lung-Ming
Department of Engineering Science, National Cheng Kung University, Tainan 701, Taiwan.
Division of Nephrology, Department of Internal Medicine, National Cheng Kung University Hospital, College of Medicine, National Cheng Kung University, Tainan 704, Taiwan.
Biosensors (Basel). 2025 Feb 12;15(2):104. doi: 10.3390/bios15020104.
A microfluidic system for detecting sodium ions (Na) has been developed, incorporating a micro finger-pump chip and a micro-spectrometer platform to measure Na concentration in human serum. A small volume (10 μL) of serum sample is introduced into the microchip and reacted with a preloaded reagent mixture through a two-step finger-pump actuation process. The resulting purple complex is directed into the detection area of the chip and analyzed using the micro-spectrometer at wavelengths of 555 and 666 nm. The Na concentration is then inversely derived from the measured A/A absorbance ratio using self-written software installed on a Raspberry Pi. The entire detection process is completed in just 3 min, offering a significant advantage in meeting clinical needs compared to the traditional reporting turnaround time of several hours in medical institutions. The experimental results indicate a linear relationship between the measured absorbance ratio and Na concentration within the range of 1-200 mM, with a correlation coefficient of R = 0.9989. Additionally, the detection results from 60 serum samples collected from chronic kidney disease (CKD) patients showed a strong agreement with those obtained using the conventional indirect ion-selective electrode (ISE) method, achieving a correlation coefficient of R = 0.9885 and an average recovery rate of 99.4%. In summary, the proposed system provides a practical, affordable, and rapid alternative to conventional Na detection methods, making it highly promising for point-of-care (POC) testing applications.
一种用于检测钠离子（Na）的微流控系统已被开发出来，它集成了一个微型指状泵芯片和一个微型光谱仪平台，用于测量人血清中的钠浓度。将少量（10μL）血清样本引入微芯片，并通过两步指状泵驱动过程与预先加载的试剂混合物反应。生成的紫色络合物被引导至芯片的检测区域，并使用微型光谱仪在555和666nm波长下进行分析。然后，使用安装在树莓派上的自编软件，根据测量的吸光度比值A/A反推钠浓度。整个检测过程仅需3分钟即可完成，与医疗机构传统的数小时报告周转时间相比，在满足临床需求方面具有显著优势。实验结果表明，在1-200mM范围内，测量的吸光度比值与钠浓度之间存在线性关系，相关系数R = 0.9989。此外，从慢性肾脏病（CKD）患者收集的60份血清样本的检测结果与使用传统间接离子选择电极（ISE）方法获得的结果高度一致，相关系数R = 0.9885，平均回收率为99.4%。总之，所提出的系统为传统钠检测方法提供了一种实用、经济且快速的替代方案，使其在即时检测（POC）应用中极具前景。
