A low-cost electric micromanipulator and its application to single-cell electroporation.

Micromanipulation techniques are essential in studies of cell function, both for single cells and for cell collectives. Various types of micromanipulators are now commercially available. Hydraulic micromanipulators have the advantage of analogue operation, allowing the user to move the glass microneedle in direct response to their own hand movements. However, they require regular maintenance to maintain their performance. On the other hand, some electric micromanipulators can operate in minute steps of several hundred nanometers, but they are expensive. This paper describes our assembly of a low-cost electric micromanipulator. The device consists of three commercially available stages, three linear DC motors to drive them, and a lab-made control circuit. Using this device, we were able to direct a glass microneedle to cut an MDCK cell sheet. We also manipulated an aspiration pipette to aspirate a portion of a Dictyostelium cell. In addition, we were able to gently touch the tip of an electroporation pipette to the surface of a single target cell in a sheet of fish epidermal keratocytes and load FITC into the cell. Our device can be assembled at one-fourth the cost of commercially available hydraulic micromanipulators. This could make it easier, both economically and technically, to add micromanipulators to all of a laboratory's microscopes.