Electrophysiology requires accurate measurements free of interference from outside sources such as electrical impulses and vibrations.
Phoenix, AZ – Electro-physiologists studying the flow of ions in biological tissues must create an environment free of electrical interference and mechanical vibration. The various recording techniques used to measure electric current or fluctuations in voltage are not reliable unless such noise is eliminated.
In order to study the electrical properties of cells and tissues, first make a connection between the inside of the cell or tissue and an amplifier. This connection is made with a glass pipette. A metal electrode or wire is connected to an amplifier, and the electrode is inserted into the pipette which is also filled with a particular solution (such as a chloride-based salt solution). The pipette is maneuvered into place against the exterior wall of a tissue or cell with micromanipulators and held in place with suction. The suction pulls wall membrane into the pipette making the electrical connection. Once the connection is made, the scientists can hold the current constant and measure changes in voltage, or vice versa. This electrophysiological recording technique is known as patch clamp. There are several variations of patch clamping.
In every instance, however, mechanical vibration and electrical interference frustrate data collection. Electrical interference can be minimized by placing a Faraday cage over the microscope workstation. Microscope manufacturers work diligently to design microscopes that do not create vibrations by virtue of their own operation. Popular models include: (1) Leica DM LFS, (2) Nikon Eclipse E600FN, (3) Olympus BX51W1/BX61W1, and the (4) Carl Zeiss Axio Imager. Nevertheless, environmental vibrations will still disrupt an electro-physiologists work.
An answer for the environmental vibration problem that does not create electrical field interference is required. An effective solution is a mechanical and passive vibration isolation bearing combined with a platform that is compact and designed for the footprint of the instrument to be isolated. Such a vibration isolation platform does not create electrical interference since it does not have air hoses or supporting computer hardware, and therefore it can be placed inside the Faraday cage.