The choice of a polymeric material for the preparation of modified release systems is a very difficult task as such materials are scarcely characterized as for this specific utilization. Infact, just the polymer's chemical composition can't sufficiently describe the material: a specific characterization is complicated and involves non standard techniques in a Pharmaceutical Technology Department. A characterization study has been carried out within the Biopharmaceutical AFI Study Group on a standard polymer, hydroxypropyl methylcellulose. Such excipient is used in the pharmaceutical field, as binder, thickener, film coating agent and as control agent in solid pharmaceutical forms. The purpose was to point out suitable aud repeatable analysis methods which allow control of materials both for the steadfastedness referred to different batches produced by the same supplier and by different suppliers. Characterization was carried out on hydroxypropyl methylcellulose (Methocel) series E. For functional characterization referring to control release a Methocel series K was used as standard polymer while diprophylline was used as drug model. Hydrophilic matrices containing different ratios of this polymer were tested to dissolution evaluating influence of the composition on the drug release kinetic. Also the influence due to introduction of a second gelling hydrophilic polymer on the different hydrophilic matrices was analyzed.
|Titolo:||Characterization of polymeric material for the preparation of modified release systems and use of gelling hydrophilic polymers|
|Parole Chiave:||controlled release; hydrophilic matrices; hydroxy propyl methylcellulose; polymer characterization|
|Settore Scientifico Disciplinare:||Settore CHIM/09 - Farmaceutico Tecnologico Applicativo|
|Data di pubblicazione:||1994|
|Appare nelle tipologie:||01 - Articolo su periodico|