Data squeezed out of bioparticles
15 Jan 2000
The Micromanipulation Group of the Centre for Bioprocess Engineering has developed novel methods for characterising the mechanical properties of microscopic biological and other types of particle.
Micromanipulation involves squeezing a particle, such as a cell, between two flat-ended probes or a probe and a glass slide, and simultaneously measuring the deformation of the particle and the force being exerted on it.
Early research showed that the force necessary to burst a hybridoma was measurable, and that other useful mechanical property information could be established from the squeezing data.
Such information has been used to understand how fluid flows can break cells in bioreactors. Following this success, methods were developed for yeast cells and bacteria, for filamentous fungi (pulling rather than squeezing), and for skin cells, starch granules and microcapsules, such as those used in carbonless paper manufacture and controlled drug release.
Most recently, work has begun on single tomato cells, as part of a study on the influence of processing on cell and cell wall mechanical behaviour, on cell flocs, which are important in biochemical product recovery and wastewater treatment, and on agglomeration.
Group leader Zhibing Zhang says: 'We have demonstrated that micromanipulation can be employed to put the squeeze on microscopic particles, to extract from them information vital in understanding and improving their behaviour in processing.'
