Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
2
pubmed:dateCreated
2008-12-29
pubmed:abstractText
The aim of this study was to evaluate the moisture-protective ability of different polymeric coatings. Free films and film-coated tablets (with cores containing freeze-dried garlic powder) were prepared using aqueous solutions/dispersions of hydroxypropyl methylcellulose (HPMC), Opadry AMB [a poly(vinylalcohol)-based formulation] and Eudragit E PO [a poly(methacrylate-methylmethacrylate)]. The water content of the systems upon open storage at 75% relative humidity (RH) and 22 degrees C (room temperature) was followed gravimetrically. Furthermore, polymer powders, free films and coated tablets were analyzed by differential scanning calorimetry (DSC) and dynamic vapor sorption (DVS). The type of polymer strongly affected the resulting water uptake kinetics of the free films and coated tablets. DSC analysis revealed whether or not significant physical changes occurred in the coatings during storage, and whether the water vapor permeability was water concentration dependent. Using DVS analysis the critical glass transition RH of Opadry AMB powder and Opadry AMB-coated tablets at 25 degrees C could be determined: 44.0% and 72.9% RH. Storage below these threshold values significantly reduces water penetration. Thus, DVS and DSC measurements can provide valuable information on the nature of polymers used for moisture protection.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Feb
pubmed:issn
1520-6017
pubmed:author
pubmed:issnType
Electronic
pubmed:volume
98
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
651-64
pubmed:meshHeading
pubmed-meshheading:18481311-Calorimetry, Differential Scanning, pubmed-meshheading:18481311-Chemistry, Pharmaceutical, pubmed-meshheading:18481311-Drug Compounding, pubmed-meshheading:18481311-Drug Stability, pubmed-meshheading:18481311-Drug Storage, pubmed-meshheading:18481311-Garlic, pubmed-meshheading:18481311-Humidity, pubmed-meshheading:18481311-Kinetics, pubmed-meshheading:18481311-Methylcellulose, pubmed-meshheading:18481311-Models, Chemical, pubmed-meshheading:18481311-Permeability, pubmed-meshheading:18481311-Plant Extracts, pubmed-meshheading:18481311-Polymers, pubmed-meshheading:18481311-Polymethacrylic Acids, pubmed-meshheading:18481311-Polyvinyls, pubmed-meshheading:18481311-Powders, pubmed-meshheading:18481311-Tablets, pubmed-meshheading:18481311-Technology, Pharmaceutical, pubmed-meshheading:18481311-Transition Temperature, pubmed-meshheading:18481311-Volatilization, pubmed-meshheading:18481311-Water
pubmed:year
2009
pubmed:articleTitle
Characterization of moisture-protective polymer coatings using differential scanning calorimetry and dynamic vapor sorption.
pubmed:affiliation
College of Pharmacy, Freie Universität Berlin, Berlin, Germany.
pubmed:publicationType
Journal Article, Evaluation Studies