A computer-interfaced falling ball viscometer.
We have developed a system that greatly facilitates viscosity measurement under low-shear conditions, based upon a falling ball viscometer interfaced to a personal computer. Three optical sensors indicate the rate of passage of a steel ball falling through a micro-capillary tube, and a potentiometer detects the angle of the tube. The resulting data are passed from a custom program with a graphical user interface to a spreadsheet. The spreadsheet then calculates and stores a value for the viscosity of the sample, using the data passed to it from the viscometer, and a look-up table of stored slope and intercept values calculated from precision viscosity standards. We used the viscometer to determine the kinetics of actin polymerization, and to measure the viscosity of F-actin-aldolase gels. This system provides significantly greater reproducibility and speed in data acquisition than does the traditional 'eyeball and stopwatch' method, and data reduction is virtually instantaneous.
Wang
J
J
Center for Bioengineering, University of Washington, Seattle, 98195.
Reitz
F
F
Donaldson
T
T
Pagliaro
L
L
D000199:Actins / Q000737:chemistry; D000818:Animals; D001704:Biopolymers; D002627:Chemistry, Physical / Q000295:instrumentation*; D011817:Rabbits; D015203:Reproducibility of Results; D012984:Software; D014584:User-Computer Interface; D014783:Viscosity
D000199:Actins; D001704:Biopolymers