Label-Free Nanopore Single-Molecule Measurement of Trypsin Activity

详细信息    查看全文

• 作者：Shuo Zhou ; Liang Wang ; Xiaohan Chen ; Xiyun Guan
• 刊名：ACS Sensor
• 出版年：2016
• 出版时间：May 27, 2016
• 年：2016
• 卷：1
• 期：5
• 页码：607-613
• 全文大小：500K
• ISSN：2379-3694

文摘

Trypsin is the most important digestive enzyme produced in the pancreas, and is a useful biomarker for pancreatitis. In this work, a rapid and sensitive method for the quantitative determination of trypsin activity is developed by using a biological α-hemolysin protein nanopore. Due to its much larger molecular diameter than the narrow pore constriction, trypsin itself cannot transport through the α-hemolysin channel. Hence, an indirect trypsin detection method is developed by monitoring its proteolytic cleavage of a lysine-containing peptide substrate. Based on the current modulations produced by the translocation of the substrate degradation products in the nanopore, the activity levels of trypsin could be determined. The method is rapid and highly sensitive, with picomolar concentrations of trypsin detected in minutes. In addition, the effects of cation and temperature on the sensor sensitivity, trypsin inhibition, and serum sample analysis are also investigated.