Electrode for Whole Cell and Other Testing

Novel "Push-Pen" Design for Patch-Clamp Electrode NU 2009-189 Inventors Dimitry A. Dikin Donald R. Cantrell Samsoon Inayat John B. Troy* Yan Zhao Abstract Northwestern researchers have developed a novel push-pen patch clamp electrode system that integrates a linear hydraulic actuator in the pipette holder. The actuator moves the metal Ag/AgCl electrode within the pipette to a position where it protrudes from the pipette orifice. This mechanism has multiple benefits in conventional whole-cell experiments. For example, it lowers the series resistance since the resistivity of the electrode is less than that of the pipette solution. The reduced series resistance permits the recording of higher bandwidth signals. Further, the push-pen operation serves as a physical structure to help remove the commonly found cellular debris clog in the pipette tip by pushing it out and clearing it. Lastly, the push-pen operation also reduces the leakage of cytosol into the pipette which results in the ability to conduct longer experiments. Applications o Ion Channel Research Advantages o Reduced series resistance o Increased recording stability for extended times o Ability to remove cellular debris o Accurate readings for smaller cellular components (e.g. neural dendrites and organelles) Publications Zhao Y, Inayat S, Dikin DA, Singer JH, Ruoff RS and Troy JB (2009) Patch Clamp Technique: Review of the current state of the art and potential contributions from nanoengineering. Proceedings of the Institution of Mechanical Engineers, Part N: Journal of Nanoengineering and Nanosystems. 222: 1-11. Inayat S, Zhao Y, Cantrell DR, Dikin DA, Pinto LH and Troy JB (2010) A Novel Way to Go Whole Cell in Patch-Clamp Experiments. IEEE Transactions on Biomedical Engineering. 57: 2764-2770. IP Status Issued US Patent No. 8,557,095 .