Zeta potential measurement and particle size analysis for a better understanding of urinary inhibitors of calcium oxalate crystallization.
To better understand urinary inhibitors of calcium oxalate crystallization, both zeta potential measurement and particle size analysis were chosen to illustrate: (1) the potential therapeutic efficacy of G872, a semi-synthetic sulfated polysaccharide, in stone prevention; and (2) the relative contribution of various urinary fractions ¿e.g., ultrafiltered urine (UFU), Tamm-Horsfall protein (THP), urinary polyanions precipitated with cetylpyridinium chloride (CPC), urinary macromolecular substances with different concentration ratios (UMS10,50,90 and UMS'10,50,90) and THP-free urine (THPFU)¿ to total urinary inhibitory activity. The results showed: (1) addition of G872 significantly enhances urinary inhibitory activity and negative zeta potential values; (2) re-addition of the CPC to UFU completely restores urinary inhibitory activity; and (3) artificial urines prepared by mixing UMS'10,50,90 from THPFU with UFU differed in inhibitory activity from that prepared by mixing UMS10,50,90 from a pooled normal urine with UFU. Based on these experimental results, the following speculations can be made: (1) normal human urines are considered to be a protective colloidal system; (2) urinary inhibitory activity originates mainly from CPC and/or UMS; (3) normal THP is a protective material to maintain urinary inhibitory activity; and (4) mutual interaction between urinary inhibitors may change the total urinary inhibitory activity.
Cao
L C
LC
Department of Urology, Erasmus University and Academic Hospital, Rotterdam, The Netherlands. cao@uro.fgg.eur.nl
Deng
G
G
Boevé
E R
ER
de Bruijn
W C
WC
de Water
R
R
Verkoelen
C F
CF
Romijn
J C
JC
Schröder
F H
FH
D002129:Calcium Oxalate / Q000737:chemistry*; D002594:Cetylpyridinium / Q000494:pharmacology; D003460:Crystallization; D006801:Humans; D007669:Kidney Calculi / Q000517:prevention & control*; D010316:Particle Size; D011134:Polysaccharides / Q000494:pharmacology; D014556:Urine / Q000737:chemistry* / Q000502:physiology
D011134:Polysaccharides; D002129:Calcium Oxalate; D002594:Cetylpyridinium