P. Schaad et al., ADSORPTION OF NEUTRAL AND ANIONIC POLYACRYLAMIDES ON HYDROXYAPATITE AND HUMAN ENAMEL - INFLUENCE ON THE DISSOLUTION KINETICS, Journal of colloid and interface science, 164(2), 1994, pp. 291-295
The adsorption of polyacrylamide fractions of different molecular weig
hts and degrees of hydrolysis on hydroxyapatite and dental enamel, as
well as their influence on the kinetics of dissolution of the latter,
are studied at a constant pH under well controlled conditions. It is s
hown that the adsorbed polymers can slow down the dissolution process.
The intensity of the inhibition effect follows the characteristics of
the adsorption layer. The inhibition increases with the molecular wei
ght of the polymers and their degree of hydrolysis. These behaviors ar
e well interpreted with the model of apatite dissolution recently prop
osed, which supposes the formation of a cationic semipermeable layer,
formed by the adsorption of calcium ions at the apatite interface. (C)
1994 Academic Press, Inc.