In this work, fast isoelectric focusing (IEF) was successfully implemented on an open paper fluidic channel for simultaneous concentration and separation of proteins from complex matrix. With this simple device, IEF can be finished in 10 min with a resolution of 0.03 pH units and concentration factor of 10, as estimated by color model proteins by smartphone-based colorimetric detection. Fast detection of albumin from human serum and glycated hemoglobin (HBA1c) from blood cell was demonstrated. In addition, off-line identification of the model proteins from the IEF fractions with matrix-assisted laser desorption ionization time-of-flight mass spectrometry (MALDI-TOF-MS) was also shown. This PAD IEF is potentially useful either for point of care test (POCT) or biomarker analysis as a cost-effective sample pretreatment method.

在这项工作中，快速等电聚焦（IEF）成功地在开放的纸质流体通道上实现，用于同时浓缩和分离复杂基质中的蛋白质。使用这种简单的设备，IEF可以在10分钟内完成，分辨率为0.03 pH单位，浓度因子为10，这是通过基于智能手机的比色检测通过颜色模型蛋白估算得出的。已证明可快速检测人血清中的白蛋白和血细胞中的糖化血红蛋白（HBA1c）。此外，还显示了通过基质辅助激光解吸电离飞行时间质谱（MALDI-TOF-MS）从IEF组分中离线鉴定模型蛋白。该PAD IEF作为一种经济高效的样品预处理方法，可能对即时检验（POCT）或生物标记分析有用。