摘要
本文研制的PC-Ⅰ型膜片钳可以分辨细胞膜上离子单通道电流信号(1pA,10kHz).在分析PC-Ⅰ原理的基础上讨论了其抑制噪声、扩展频带、输入杂散电容和输入电阻的补偿技术.给出了PC-Ⅰ的1GΩ/0.1GΩ探头内用机械开关切换对杂散电容敏感的高阻值反馈电阻的有效方法。在信噪比足够高的条件下,仪器的测量误差≤2％。
The type POI patch clamp is a device with a high current resolution for single-channel ionic recording(1pA, 10 kHz) from biomembranes. The working principle of PC-I, the compensation of stray parameters and the low noise probe design are described. It has been found that the noise levels of the two FETs of an input dual-JFET U401 are different. Hence the proper selection of the input FET will be helpful as far as the reduction of system noise is concerned. The stray capacitance in the probe is always a problem for the feedback resistor with a great resistance (100 Mohm), especially when the exchange of these resistors by switches is desired. This has now been overcome with the mechanical switches used. The overall error of PC-I is less than 2%.
出处
《华中理工大学学报》
CSCD
北大核心
1990年第3期123-130,共8页
Journal of Huazhong University of Science and Technology
基金
国家自然科学基金
关键词
膜片钳设计
电流噪声
探头
参数
Patch clamp
Current noise
Probe technology
Stray parameters compensation
