Robotic Inside-Out Patch Clamp System for Adherent Cells Based on Vesicle Rupture Control

Abstract

The inside-out patch clamp technique has been widely applied in brain science and neuroscience research due to its ability to detect extremely weak currents flowing through a single ion channel. The current manual inside-out patch clamp operations are highly expertise-requisite and low efficient. Meanwhile, the existing robotic systems are only applicable for suspended cells due to their new system setups. For the first time, this letter proposed a robotic inside-out patch clamp system for adherent cells based on vesicle rupture control. Firstly, impedance models were established to detect the vesicle rupture state. Then, a force analysis that combines the defocusing imaging model was developed to precisely control the exposure time of the vesicle in the air, which is a key factor in the rupture process of the vesicle. Based on the above works, a robotic inside-out patch clamp process for adherent cells was established. Experimental results demonstrate that the proposed robotic system can detect vesicle rupture state with a 100% success rate, control exposure time with an average error of 0.02$\,\text{s}$ and operate adherent HEK-293 cells with a success rate of 70% at an average operation speed of 61.3$\,$seconds/cell. The success rate of our system is more than three times that of manual operation results, laying a solid foundation for subsequent single ion channel functionality research.