毛细管电泳技术在聚乙二醇化蛋白药物质量控制中的应用

Capillary electrophoresis and its application in quality control of PEGylated protein medicine

毛细管电泳是一种以高压电场为驱动力,熔融石英毛细管为分离通道的液相微分离技术。该技术样品消耗量少,分离模式灵活多样,能够检测氨基酸、多肽、蛋白质、细胞、病毒颗粒等多种生物样品,较高效液相色谱有更强的样品适应性。目前,该技术呈现了与其他分析技术联用,检测体系芯片化,检测通量不断提高的发展趋势。蛋白分子异质性分析是蛋白质药物质量控制的重要方面。由于聚乙二醇分子本身具有一定程度的异质性,蛋白聚乙二醇化的过程也有可能引入新杂质,因此聚乙二醇化蛋白药物异质性分析更加必要。聚乙二醇修饰蛋白药物质量控制需要说明蛋白质上连接聚乙二醇分子的数量和位置,即需要检测蛋白的聚乙二醇修饰率和聚乙二醇修饰位点。通过回顾近几年毛细管电泳在聚乙二醇化蛋白药物质量控制中的应用,说明不论是传统毛细管电泳系统还是芯片毛细管电泳系统都能够实现多种蛋白药物聚乙二醇修饰率检测,通过毛细管电泳与质谱联用也能够分析蛋白药物聚乙二醇修饰位点。毛细管电泳与应用非常广泛的分子排阻色谱和聚丙烯酰胺凝胶电泳相比,具有分离效果好,分析速度快,定量准确的优势。综上所述,毛细管电泳技术是聚乙二醇化蛋白药物质量控制的一种重要技术手段,在聚乙二醇化蛋白质量控制方面具有广阔的应用前景。

Capillary electrophoresis is a liquid phase micro-separation technology,which is performed on a fused silica capillary channel and driven by high voltage electric field. Separation using capillary electrophoresis offers many advantages compared with that of high performance liquid ble separation modules, and higher sample adaptability. It chromatography, including low sample consumption, flexihas been successfully applied in separation of a variety of biological samples, such as amino acids, proteins, cells and virus particles. Currently, there is a trend for capillary electrophoresis to be used in combination with other analytical techniques, such as mass spectroscopy. Furthermore, microchips have replaced traditional detection unit to facilitate high-throughput sample processing. For protein ther- apeutics, molecular heterogeneity analysis is an important aspect of quality control. Due to the inherent heterogeneity of polyethylene glycol （PEG）molecule and impurities brought by PEGylation process, it is vital to analyze the hetero- geneity of PEGylated proteins by determining the number and location of PEG molecules adhered to the protein. As demonstrated by various studies, the number of PEG molecules adhered to protein is determined by protein modification rate, which can be obtained using traditional or microchip capillary electrophoresis. PEG modification site is usually determined by combining capillary electrophoresis with mass spectrometry. Compared with the molecular exclusion chromatography and polyacrylamide gel electrophoresis, capillary electrophoresis provides more powerful separation ability, higher analyzing speed, and higher accuracy of quantitation. In summary, capillary electrophoresis technology has played an important part in quality control of the PEGylated proteins.