Scientists in the Department of Biochemistry at the University of the Pacific have been using a Brookhaven Instruments ZetaPALS System to investigate the mechanisms behind biological energy transduction. The electrical properties of contractile proteins like actin, myosin, tubulin and members of the kinesin family are being studied, having been isolated from tissues include muscle and brain. When mixed with ATP, these proteins move around and change their shape, which is reflected in their hydrodynamic size. The scientists are studying what conformational changes could be responsible. ZetaPALS is a particle size and zeta potential analyzer with a wide range capability, from macromolecular dimensions up to a micron or more. The instrument in discussion here has been fitted with a MI-SM50 small volume cell, to allow manipulation of tiny quantities of samples to follow reactions in small time. In combination with a BI-APD avalanche photodiode array detector, the ZetaPALS provides a ten-fold increase in sensitivity, even at low sample concentrations.