dc.contributor.author | Nyamweya, Nasser | |
dc.contributor.author | Mehta, Ketan A | |
dc.contributor.author | Hoag, Stephen W. | |
dc.date.accessioned | 2013-02-22T11:54:54Z | |
dc.date.issued | 2001 | |
dc.identifier.citation | Journal of Pharmaceutical Sciences, Vol. 90, (2001) | en |
dc.identifier.uri | http://erepository.uonbi.ac.ke:8080/xmlui/handle/123456789/10764 | |
dc.identifier.uri | http://www.ncbi.nlm.nih.gov/pubmed/11745752 | |
dc.description.abstract | Instability in film coating formulations can arise from interactions
between aluminum lake pigments and aqueous polymeric dispersions. The purpose of
this study was to characterize the interactions between three polymethacrylate-based
aqueous polymeric dispersions (Eudragit1 RS 30 D, Eudragit1 L 30 D-55, and
Eudragit1 NE 30 D) and aluminum lakes. Particle size measurements, pH stability
profiles, zeta potential measurements, and microscopy were used to study mixed
dispersions of the polymeric latices and the lakes. Interactions leading to dispersion
instability were related to the surface charge of the components in the formulation.
Interactions between the ionic polymers and the lakes arose from instability of the lakes
outside a certain pH range resulting in the release of electrolytes, which led to
aggregation of the polymeric particles. Interactions between the nonionic polymer and
the lakes were related to the polymer modifying the surface charge of the lakes,
resulting in aggregation of the pigment particles. | en |
dc.language.iso | en | en |
dc.subject | Film coating; | en |
dc.subject | Latex dispersions; | en |
dc.subject | Lake pigments; | en |
dc.subject | Stability; | en |
dc.subject | Zeta potential | en |
dc.title | Characterization of the interactions between polymethacrylate-based aqueous polymeric dispersions and aluminum lakes | en |
dc.type | Article | en |
local.publisher | Pharmaceutical Sciences, University of Maryland, School of Pharmacy, | en |
local.publisher | Rohm Pharma Polymers, Degussa Corporation | en |