Sun Na-Na, Xu Qin-Feng, Yang Meng-di, Wang Rui-Hong, Shu Guo-Wei, Li Guo-Liang
School of Food Science and Engineering, National R&D Center for Goat Dairy Products Processing Technology, Shaanxi University of Science and Technology, Xi'an 710021, China.
School of Food Science and Engineering, National R&D Center for Goat Dairy Products Processing Technology, Shaanxi University of Science and Technology, Xi'an 710021, China.
Int J Biol Macromol. 2025 Jan;286:138265. doi: 10.1016/j.ijbiomac.2024.138265. Epub 2024 Dec 2.
Aptamers are attractive recognition ligands for sensing proteins due to their favorable affinity, specificity, stability, and easy synthesis. However, it is difficult to detect proteins directly in complex biological samples without sophisticated equipment or tedious sample pretreatment. Herein, we developed a portable electrophoretic mobility shift assay (EMSA) platform for direct protein aptasensing in complex biological samples. This portable EMSA consists of a mini agarose gel apparatus and a simple blue light transmission instrument integrated a smartphone camera. Lactoferrin (LF), which plays critical roles in food quality and dry eye diagnosis, was selected for feasibility verification. The successful direct determination of LF in dairy samples revealed that agarose gel not only provides separation power for the LF-aptamer complex but also functions as a physical barrier, excluding milk fat globules and casein micelles and further eliminating their interference. In addition, this pretreatment-free approach also exhibits good generality and multiplexity for other proteins assay by altering aptamer sequences. Therefore, the portable EMSA could be a reliable, affordable, user-friendly and pretreatment-free tool for protein aptasensing in biological and clinical samples for point-of-need diagnostics as well as food quality and safety.
适体因其良好的亲和力、特异性、稳定性和易于合成，是用于传感蛋白质的有吸引力的识别配体。然而，在没有精密设备或繁琐样品预处理的情况下，很难在复杂生物样品中直接检测蛋白质。在此，我们开发了一种便携式电泳迁移率变动分析（EMSA）平台，用于在复杂生物样品中直接进行蛋白质适体传感。这种便携式EMSA由一个微型琼脂糖凝胶装置和一个集成了智能手机摄像头的简单蓝光透射仪组成。选择在食品质量和干眼症诊断中起关键作用的乳铁蛋白（LF）进行可行性验证。在乳制品样品中成功直接测定LF表明，琼脂糖凝胶不仅为LF-适体复合物提供分离能力，还起到物理屏障的作用，排除乳脂肪球和酪蛋白胶束，并进一步消除它们的干扰。此外，这种无需预处理的方法通过改变适体序列，对其他蛋白质检测也表现出良好的通用性和多重性。因此，便携式EMSA可以成为一种可靠、经济实惠、用户友好且无需预处理的工具，用于生物和临床样品中的蛋白质适体传感，以满足即时诊断以及食品质量和安全的需求。
