patchclamping

Patch clamping is a laboratory technique used in electrophysiology to study the electrical properties of biological membranes, particularly ion channels. It involves isolating a small patch of the cell membrane and measuring the electrical current flowing through it. This is achieved using a fine-tipped glass pipette, or micropipette, which is carefully brought into contact with the cell membrane. A tight seal, known as a gigaohm seal, is formed between the pipette tip and the membrane.

Once the seal is established, the researcher can manipulate the membrane patch in several ways. They can record the current flow across the intact membrane patch under different voltage conditions. Alternatively, the patch can be detached from the cell, allowing for the study of the properties of a single ion channel or a small group of channels in isolation. This method enables precise control over the environment surrounding the membrane patch and allows for detailed analysis of ion channel function, including their gating kinetics, ion selectivity, and pharmacology.

Patch clamping has been instrumental in advancing our understanding of cellular excitability, neuronal signaling, muscle function, and various physiological and pathological processes involving ion channels. Variations of the technique, such as whole-cell recording, cell-attached recording, inside-out, and outside-out recording, offer different experimental advantages depending on the specific research question. The development of patch clamping earned Erwin Neher and Bert Sakmann the Nobel Prize in Physiology or Medicine in 1991.