<abstract xml:lang="en" xmlns="http://www.w3.org/1999/xhtml">Stable co-polymer [vinyl acetate-co-3-dimethyl(methacryloyloxyethyl) ammonium propane sulfonate, p(VA-co-DMAPS)] latex of different compositions has been synthesized for the first time by emulsifier-free emulsion copolymerization. The unusual >>overshooting&lt;&lt; behavior of the co-polymer tablets has been explained by the formation of specific clusters from the opposite oriented dipoles-zwitterionic species. The change of their concentration with the DMAPS unit fraction (mDMAPS), pH and ionic strength has been considered responsible for the differences observed in the swelling kinetics. The results obtained prove that mDMAPS and ionic strength could be used to control the swelling degree of the p(VA-co-DMAPS) matrices and their sustained drug delivery. In this way, p(VA-co-DMAPS) matrices could be effectively used to control the sustained release of drugs with basic properties like verapamil hydrochloride from model tablets.</abstract>

Stable co-polymer [vinyl acetate-co-3-dimethyl(methacryloyloxyethyl) ammonium propane sulfonate, p(VA-co-DMAPS)] latex of different compositions has been synthesized for the first time by emulsifier-free emulsion copolymerization. The unusual >>overshooting<< behavior of the co-polymer tablets has been explained by the formation of specific clusters from the opposite oriented dipoles-zwitterionic species. The change of their concentration with the DMAPS unit fraction (mDMAPS), pH and ionic strength has been considered responsible for the differences observed in the swelling kinetics. The results obtained prove that mDMAPS and ionic strength could be used to control the swelling degree of the p(VA-co-DMAPS) matrices and their sustained drug delivery. In this way, p(VA-co-DMAPS) matrices could be effectively used to control the sustained release of drugs with basic properties like verapamil hydrochloride from model tablets.

New co-polymer zwitterionic matrices for sustained release of verapamil hydrochloride

Department of Pharmaceutical Technology and Biopharmacy, Faculty of Pharmacy, Medical University, Sofia-1000, Bulgaria

Acta Pharmaceutica

Stable co-polymer [vinyl acetate-co-3-dimethyl(methacryloyloxyethyl) ammonium propane sulfonate, p(VA-co-DMAPS)] latex of different compositions has been...

New co-polymer zwitterionic matrices for sustained release of verapamil hydrochloride

Published Online: Dec 28, 2007

Page range: 429 - 439

DOI: https://doi.org/10.2478/v10007-007-0034-4

Keywords
kopolimer [vinil acetat-ko-3-dimetil(metakriloiloksietill)amonijev propan sulfonat, emulzijska kopolimerizacija bez emulgatora, polizwitterion, dipol-dipol klasteri, bubrenje, matriksne tablete, isporuka lijekova

This content is open access.

New co-polymer zwitterionic matrices for sustained release of verapamil hydrochloride

Published Online: Dec 28, 2007

Page range: 429 - 439

DOI: https://doi.org/10.2478/v10007-007-0034-4

Keywordskopolimer [vinil acetat-ko-3-dimetil(metakriloiloksietill)amonijev propan sulfonat, emulzijska kopolimerizacija bez emulgatora, polizwitterion, dipol-dipol klasteri, bubrenje, matriksne tablete, isporuka lijekova

This content is open access.

Keywords
kopolimer [vinil acetat-ko-3-dimetil(metakriloiloksietill)amonijev propan sulfonat, emulzijska kopolimerizacija bez emulgatora, polizwitterion, dipol-dipol klasteri, bubrenje, matriksne tablete, isporuka lijekova