title: A simple electronic capillary microviscometer.
abstract: Inexpensive electronic components were adapted to a miniaturized version of a falling-ball viscometer. This allowed automatic determination of relative viscosities of Newtonian fluids with 1% accuracy and employing only 10 to 30 microliters of sample or about 1 microgram of some biological materials. The electronic microviscometer was tested with bidistilled water at several temperatures, with CS2SO4 and glycerol solutions, several organic liquids, and some preparations of high-molecular-weight hyaluronic acid. Details of construction, circuitry, temperature control, operating procedure, and calculations are given as well as an evaluation of the instrument's performance in terms of previously established criteria.
mesh_terms: D000818:Animals; D004581:Electronics; D006820:Hyaluronic Acid / Q000032:analysis; D011817:Rabbits; D013582:Synovial Fluid / Q000032:analysis; D013696:Temperature; D014783:Viscosity / Q000295:instrumentation*; D014867:Water / Q000032:analysis
chemical_list: D014867:Water; D006820:Hyaluronic Acid