الفهرس 
General IntroductionOnly 14 pages are availabe for public view
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Abstract
Great advances have been made towards novel drug delivery systems over the past several years. Among such systems, the use of interpolymer interactions and formation of interpolymer complexes (IPCs). Such phenomena have been the focus of intensive applied researches as these interpolymer complexes may possess unique properties that are different from those of individual components. Furthermore, these complexes offer greater advantages for drugs through improving/and altering their physicochemical characters as stability and dissolution. Also, they have been extensively studied in the development of controlled drug release systems. The main objectives in this investigation were; firstly, to prepare chitosan or Eudragit E IPCs with different anionic polymers as sodium alginate, sodium CMC and pectin. Ketoprofen tablets were formulated using the prepared IPCs or physical mixtures of polymers in different ratios. The physical properties and in-vitro release characteristics of these tablets were evaluated. Furthermore, the accelerated stability and bioavailability of ketoprofen tablets from selected formulae were studied. Secondly, to prepare IPCs of chitosan or Eudragit E with carbopol 934. Also, IPCs loaded with diltiazem hydrochloride (DTZ HCl) were prepared and characterized. Tablets were formulated using the drug loaded IPCs or physical mixtures of polymers with drug in different drug to polymer ratios. The physical properties and in-vitro release characteristics of these tablets were studied. Also, the accelerated stability and bioavailability of DTZ HCl from selected formulae were evaluated. The obtained results revealed that, the in-vitro release profiles from the prepared tablets was dependant on the type of the IPC used, physical mixtures of polymers and their ratios, in addition to, the pH of the dissolution medium. Also, Ketoprofen tablets prepared using Eudragit E – sod. CMC IPC and their physical mixture of ratio 1:1 or chitosan – sod. CMC physical mixture of ratio 1:1 as matrices showed controlled release effect compared to chitosan - sod. CMC IPC tablets. This controlled effect was proved by low Cmax and long Tmax values. Also, Ketoprofen tablets prepared using Eudragit E – sod. CMC IPC and their physical mixture of ratio 1:1 showed higher bioavailability in comparison to that containing chitosan – sod. CMC IPC and their physical mixture of ratio 1:1 which proved by high AUC0-24 values. Also, the obtained results revealed that, the in-vitro release profiles of diltiazem hydrochloride from the prepared tablets was dependant on the type of the IPC used, physical mixtures of polymers and drug:polymer ratios. Also, it was found that, formulae as; Eud. E – carbopol IPC & their physical mixture 1:5 were physically and chemically stable. In addition, they showed more controlled release effect as illustrated by low Cmax and delayed Tmax values in comparison to Altiazem® & chitosan – carbopol IPC tablets. Furthermore, the bioavailability of DTZ HCl was increased by 21.11 and 31.41 % for chitosan – carbopol IPC & Eud. E – carbopol tablets, respectively, while it increased only by 11.25% for Eud. E – carbopol physical mixture tablets relative to Altiazem® tablets.