New Micro-Injection Chip for Cell Injections

Photo: A man injects a substance under the microscope

Cell injection is a versatile method to bring various substances into biological cells. Commercially available cell injection systems consist of a micro needle, a pump and a tubing connecting these both components. This macroscopic setup is suboptimal for injecting substances into cells which are in the micrometer range. In particular, it is difficult to dose typical volumes of 0.1 - 0.3 pl in a reproducible manner. Due to this difficulty many cells burst during the injection procedure.

Furthermore a very experienced operator is needed to exactly adjust the parameters like pump pressure, duration of injection and velocity of needle movement of the complex injection system.

At Fraunhofer IBMT a new micro-injection chip for cell injections has been developed. The IBMT chip monolithically integrates a micro needle, a thermo pneumatic micro pump connected to this needle, and a sensor. The dimensions of the chip are 2.2 x 2.2 x 1 mm3. The micro needle as well as the area around the micro needle are made of translucent materials such as silicon dioxide. Filling of the chip is done by simply dipping the needle into the fluid to be injected.

In contrast to commercially available injection systems the size of connecting tube and pump of the IBMT chip is adapted to the volume to be injected. Once filled, the chip can be used to perform several hundreds of injections. The injection volume can be adjusted and controlled very precisely.

The injection chip can be easily used with a micro robot. When using such a combination performing micro injections requires much less dexterity than with state of the art injection systems..; Quelle: Fraunhofer-Institut für Biomedizinische Technik IBMT