Automated patch clamp revolutionizes the patch clamp technique making it easier to use and increasing throughput. Automated patch clamp uses a planar borosilicate glass chip rather a fine glass pipette used in conventional patch clamp. The planar glass chip contains a small hole and suction is used from underneath to attract a cell to the hole and form a good seal between the glass and the cell membrane. Electrical currents are measured in the same way and the data quality is comparable between the two techniques.
Lipid bilayers are the main structural component of any cell membrane. They contain a variety of lipid types, diverse proteins, and structures which influence the properties and function of the cell and the membrane itself. The complexity of such systems poses a challenge when investigating isolated processes occurring in lipid bilayers. Working with proteins reconstituted in artificial membranes or native, purified membrane fragments are both strategies to reduce the complexity of such studies. Artificial bilayer recordings reveal the actions of single ion channels in real-time, thereby gaining detailed insights into ion channel function, and how bilayer or buffer compositions affect the ion channel. Proteins involved in membrane transport, however, are generally low-conducting. Here, a capacitive read-out from the transporter population has proven successful, either from liposomes or native membrane fractions immobilized on a solid-supported membrane-coated electrode.
Fast, label-free, and real-time cellular readouts such as impedance assays, extracellular electrical activity, and contractile force recordings, have proven to be excellent methods for monitoring cell activity, viability, and connectivity. When the cells adhere, proliferate, or die, they gradually prevent or enable the flow of electric current through the electrodes integrated into the culture plate, leading to impedance field change. The single and multifrequency impedance readouts recorded of planar gold-film electrodes reveal changes in cell adhesion and cell-specific structural changes. This provides valuable insights into various cell phenotypes, even over prolonged periods of time, with the crucial advantage of continuous cell monitoring.
