K. Furusawa et K. Uchiyama, COLLABORATIVE STUDIES OF ZETA-POTENTIAL MEASUREMENTS AND ELECTROPHORETIC MEASUREMENTS USING REFERENCE SAMPLE, Colloids and surfaces. A, Physicochemical and engineering aspects, 140(1-3), 1998, pp. 217-226
Simultaneous measurements of zeta-potential for two standard latex sus
pensions were carried out so as to assess the reliability of each of t
hese measurement techniques and find means for their improvement. Furt
hermore, syntheses of a reference particle dispersion stabilized steri
cally in an aqueous medium without any electrostatic effects and measu
rements of zeta-potential using the reference dispersion as a standard
were performed under various experimental conditions. It became appar
ent that the dense adsorption layer of hydroxypropylcellulose (HPC), w
ith a lower critical solution temperature (LCST), formed on latex part
icles with a low surface charge density at temperatures higher than th
e LCST, plays a role in completely shielding the electrostatic effect
arising from the surface charge on the bare particles. Such reference
particles with zero zeta-potential allow us to determine the.electroph
oretic mobility of unknown samples at the one-half depth in the electr
ophoretic cell by subtracting the mobility of the reference sample at
the same level. Furthermore, the zeta-potential of the cell wall can b
e easily determined from the mobility of the reference sample, because
the apparent velocity profile of the reference sample indicates the l
iquid flow velocity in the cell. (C) 1998 Elsevier Science B.V. All ri
ghts reserved.