Impact of crystalline form changing on behavior of microcapsules prepared from three-component gel system.
In this paper, the effect of anhydrous-monohydrate process-induced transformation of theophylline was examined in microcapsules produced by in situ gelation method using sodium alginate, hydroxypropylmethylcellulose and hydroxyethylcellulose. Films produced from gel were applied to characterize the changes by NIR spectroscopy, X-ray, DSC method and stereomicroscopy because it is easier to study that in films in the case of gel systems used in situ gelation process. The properties of end-product are influenced by the swelling ability, equilibrium water uptake, release profile and encapsulation efficiency. Water penetration and drug release were evaluated by Davidson-Peppas and Korsmeyer-Peppas models. The ex tempore formed monohydrate crystals were smaller and built into the matrix structure in a greater extent. Increased drug release, matrix erosion and diffuse reflectance values at 1470 and 1950 nm were observed added theophylline later into the gel because of developing a denser structure.
Department of Pharmaceutics, Semmelweis University, Budapest, Hungary. zsfenyvesi@gmail.com
Zsófia
Z
Fenyvesi
Khaled Omaru A
KO
Ashour
Romána
R
Zelkó
Ulrich
U
Müller
István
I
Antal
Imre
I
Klebovich
Sylvia
S
Marton
D000464:Alginates / Q000737:chemistry; D001993:Bronchodilator Agents / Q000008:administration & dosage* / Q000737:chemistry; D002214:Capsules; D002482:Cellulose / Q000031:analogs & derivatives / Q000737:chemistry; D003460:Crystallization; D005782:Gels; D020723:Glucuronic Acid / Q000737:chemistry; D006603:Hexuronic Acids / Q000737:chemistry; D065347:Hypromellose Derivatives; D008747:Methylcellulose / Q000031:analogs & derivatives / Q000737:chemistry; D008956:Models, Chemical; D011108:Polymers / Q000737:chemistry*; D013806:Theophylline / Q000008:administration & dosage* / Q000737:chemistry; D014867:Water / Q000737:chemistry
D000464:Alginates; D001993:Bronchodilator Agents; D002214:Capsules; D005782:Gels; D006603:Hexuronic Acids; D011108:Polymers; D014867:Water; D065347:Hypromellose Derivatives; D020723:Glucuronic Acid; D002482:Cellulose; C002283:hydroxyethylcellulose; D008747:Methylcellulose; D013806:Theophylline