New materials in biomedical micromanipulation
The micropipette-based and other types of micromanipulators that are currently employed for biological application lack accurate force control and may cause damage to the cells or tissues. Conventional electric motors and their associated gear boxes have also reached their limits despite their miniaturisation. Funded by the EU, the POLYACT (Polymer microactuators for biomedicine) project worked to develop soft, flexible micromanipulators for the handling of biological objects and surgical tools for minimal invasive surgery. The goal was to create tools with minimal dimensions of 100 µm to 1 mm in size, which is up to two orders of magnitude smaller than existing micromanipulators. The project’s main objective was fabrication of polymeric microactuators that can be individually controlled. The critical attribute of these actuators is that they require little electric power (20-30 mW) and low voltage (1-2 V). Researchers evaluated two new fabrication methods to produce soft flexible microactuators. Using these methods, they developed two generations of microactuators based on conducting polymer for micromanipulation of soft objects. The first generation is based on a PVDF membrane and individually controllable actuators. The second generation is based on an ionic material (interpenetrating polymer network). POLYACT partners developed a novel process to pattern highly conductive polymer electrodes. This enabled the fabrication of all polymer microactuators, as demonstrated by the second-generation devices. These new soft microactuators can be used in microrobotic applications in biomedicine and for handling cells and tissues in culture.
Keywords
Micromanipulators, biomedicine, POLYACT, polymer, microactuators