ABSTRACT
A carrier and an oral absorbent for the treatment of chronic diseases in the form of a tablet was prepared from granulated chitosan (G-CS) particles. The resulting tablet was highly dispersible and disintegrated rapidly (< 30 s) in aqueous media. The non-granulated chitosan (N-CS) powder partially crystallized (2θ = 12-15° and 20°) during wet granulation to give G-CS crystalline particles. The rate of penetration of water into G-CS aggregates was markedly faster than that for N-CS aggregates, as evidenced by the ease of disintegration of the tablets. The rapid disintegration and dispersion of the tablets in vivo was confirmed by MRI measurements after the oral administration of the both tablets to rats. Some ureic toxins were adsorbed more strongly to G-CS tablets than on N-CS tablets. The results suggest that G-CS tablets have great potential for use as a fast disintegrating carrier and as an oral adsorbent in lifestyle-related diseases.
Subject(s)
Chitosan/administration & dosage , Chitosan/chemistry , Life Style , Sorption Detoxification/methods , Tablets/administration & dosage , Tablets/chemistry , Administration, Oral , Adsorption , Animals , Chitosan/metabolism , Chronic Disease/drug therapy , Crystallization , Drug Carriers/chemistry , Gastrointestinal Tract/diagnostic imaging , Gastrointestinal Tract/metabolism , Magnetic Resonance Imaging , Male , Powders/chemistry , Rats , Rats, Wistar , Tablets/metabolism , Temperature , Water/chemistryABSTRACT
Sustained-release olmesartan tablets (OLM) were prepared by the simple, direct compression of composites of anionic sulfobutyl ether-ß-cyclodextrin (SBE-ß-CD) and cationic spray-dried chitosan (SD-CS), and were evaluated for use as a sustained release preparation for the treatment of hypertension. An investigation of the interaction between OLM and SBE-ß-CD by the solubility method indicated that the phase diagram of the OLM/SBE-ß-CD system was the AL type, indicating the formation of a 1:1 inclusion complex. The release of OLM from tablets composed of the SD-CS/SBE-ß-CD composite was slow in media at both pH 1.2 and at 6.8. The in vitro slow release characteristics of the SD-CS/SBE-ß-CD composite were reflected in the in vivo absorption of the drug after normal rats were given an oral administration of the preparation. Furthermore, the SD-CS/SBE-ß-CD composite continuously increased the antihypertensive effect of OLM in hypertensive rats, compared with that of the drug itself. These results suggest that a simple mixing of SD-CS and SBE-ß-CD can be potentially useful for the controlled release of a drug for the continuous treatments of hypertension.
