Cell Penetrators stab a pipette forward with great force over micron distances. The abrupt stab avoids dimpling or deforming the cell membrane as it creates a sudden passage all the way through the cell membrane. The result is a much improved yield of successful penetrations over that achieved by micromanipulation alone.
Even the penetration of very adamant cells or resilient cell membranes can be performed easily. Front panel knobs allow the setting of the penetration speed and depth of forward advance. The withdrawal speed is set independently of the penetration speed.
PM20 model is optimized for cell injection, with access to the back of the pipette. The PM10 model is optomized for intracellular electrophysiology with a novel design feature. After the forward stab, the piezo crystal is relaxed, which would withdraw the pipette, except it is done at exactly the same rate as slower DC motors move the entire pipette forward, for no net movement of the tip, but the piezo is reloaded for another stab.