title: Polymers for use in controlled release systems: the effect of surfactants on their swelling properties.
abstract: The effect of an ampholytic surfactant on the swelling properties of polymeric materials was studied, using various swelling liquids. Tablets were prepared consisting of hydroxypropyl methylcellulose, poly(oxyethylene) and sodium alginate. Tego betain was the non-ionic surfactant used as an additive in a series of samples made of the above polymers. Those tablets were immersed in distilled water, phosphate buffer and 0.1 N HCl, and their weight uptake was recorded as a function of time, in order to assess the swelling process. Measurements of the contact angle of the above systems were also carried out for estimating their wetting properties. The results of this study showed a selectivity among polymers, surfactant and surrounding liquid. Clearly, an enhancement of the swelling capacity of hydroxypropyl methylcellulose tablets due to the surfactant was recorded. An unclear effect was observed in the case of poly(oxyethylene), whereas for sodium alginate, the dominant factor is its water solubility that controls swelling behaviour.
authors.affiliation: Department of Pharmacy, University of Athens, Greece.
authors.forename: M
authors.initials: M
authors.lastname: Vlachou
authors.forename: N
authors.initials: N
authors.lastname: Hani
authors.forename: M
authors.initials: M
authors.lastname: Efentakis
authors.forename: P A
authors.initials: PA
authors.lastname: Tarantili
authors.forename: A G
authors.initials: AG
authors.lastname: Andreopoulos
mesh_terms: D000327:Adsorption; D000464:Alginates / Q000737:chemistry; D001622:Betaine / Q000031:analogs & derivatives* / Q000737:chemistry; D002021:Buffers; D003692:Delayed-Action Preparations; D004337:Drug Carriers; D016503:Drug Delivery Systems; D020723:Glucuronic Acid; D006603:Hexuronic Acids; D006801:Humans; D065347:Hypromellose Derivatives; D008422:Materials Testing; D008747:Methylcellulose / Q000031:analogs & derivatives* / Q000737:chemistry; D010710:Phosphates / Q000737:chemistry; D011092:Polyethylene Glycols / Q000737:chemistry; D011108:Polymers / Q000737:chemistry*; D011409:Propylene Glycols / Q000737:chemistry; D012995:Solubility; D013499:Surface Properties; D013501:Surface-Active Agents / Q000737:chemistry*; D013607:Tablets; D013997:Time Factors; D014867:Water / Q000737:chemistry; D017155:Wettability
chemical_list: D000464:Alginates; D002021:Buffers; D003692:Delayed-Action Preparations; D004337:Drug Carriers; D006603:Hexuronic Acids; C116176:PEO-PPO-PEO; D010710:Phosphates; D011108:Polymers; D011409:Propylene Glycols; D013501:Surface-Active Agents; D013607:Tablets; D014867:Water; D065347:Hypromellose Derivatives; D001622:Betaine; D011092:Polyethylene Glycols; C065099:Tego-Betain; D020723:Glucuronic Acid; D008747:Methylcellulose