α₁-Acid glycoprotein (AGP) is a glycoprotein present in serum, which is associated with the modulation of the immune system in response to stress or injuries, and a biomarker for inflammatory diseases and cancers. Here, we propose a pump-free microfluidic device for the electrochemical determination of AGP. The microfluidic device utilizes capillary-driven flow and a passive mixing system to label the AGP with the Os (VI) complex (an electrochemical tag) inside the main channel, before delivering the products to the electrode surface. Furthermore, thanks to the resulting geometry, all the analytical steps can be carried out inside the device: labeling, washing, and detection by adsorptive transfer stripping square wave voltammetry. The microfluidic device exhibited a linear range from 500 to 2000 mg L^–1 (R² = 0.990) and adequate limit of detection (LOD = 231 mg L^–1). Commercial serum samples were analyzed to demonstrate the success of the method, yielding recoveries around 83%. Due to its simplicity, low sample consumption, low cost, short analysis time, disposability, and portability, the proposed method can serve as a point-of-care/need testing device for AGP.

中文翻译：

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用于α1-酸糖蛋白电化学检测的无泵微流体装置

α _{1 -}酸性糖蛋白 (AGP) 是一种存在于血清中的糖蛋白，它与免疫系统对压力或损伤作出反应的调节有关，也是炎症性疾病和癌症的生物标志物。在这里，我们提出了一种用于电化学测定 AGP 的无泵微流体装置。微流体装置利用毛细管驱动的流动和被动混合系统，在将产品输送到电极表面之前，在主通道内用 Os (VI) 复合物（电化学标签）标记 AGP。此外，由于所产生的几何形状，所有分析步骤都可以在设备内进行：标记、洗涤和通过吸附转移剥离方波伏安法进行检测。微流体装置表现出从 500 到 2000 mg L 的线性范围^–1 ( R ² = 0.990) 和足够的检测限 (LOD = 231 mg L ^–1 )。分析商业血清样品以证明该方法的成功，回收率约为 83%。由于其简单、样品消耗低、成本低、分析时间短、一次性和便携性，所提出的方法可用作 AGP 的即时/需要测试设备。