ABSTRACT
The purpose of this research was to develop and evaluate controlled release matrix tablets of paracetamol based on natural gum exudates of Albizia procera. Procera gum was characterized of its properties like compressibility index, angle of repose, viscosity and moisture content. The interaction between the gum and paracetamol was also studied through differential scanning calorimetry (DSC) and FTIR spectroscopy. Matrix tablets were then prepared by wet granulation method with different concentrations of procera gum and hydroxypropyl methylcellulose (HPMC) and evaluated for their physical properties like weight variation, hardness, friability and content uniformity. Dissolution study was conducted to characterize release mechanism from the matrix system and data were fitted to various kinetic models. The mechanism of drug release from both types of matrix tablets was found to be anomalous type. Results from various evaluations suggested that A. procera gum could be used as drug release retardant in controlled release matrix systems.
Subject(s)
Albizzia , Dental Porcelain/chemistry , Excipients/chemistry , Metal Ceramic Alloys/chemistry , Plant Gums/chemistry , Titanium/chemistry , Administration, Oral , Delayed-Action Preparations , Dental Porcelain/metabolism , Excipients/metabolism , Metal Ceramic Alloys/metabolism , Plant Extracts/chemistry , Plant Extracts/metabolism , Plant Gums/metabolism , Tablets , Titanium/metabolismABSTRACT
Aluminium release from an alumina bioceramic was investigated parallel to standardized biocompatibility testing in an animal experiment. Alumina implants were introduced into both femurs of male rats and into the mandible of male guinea-pigs. After a period of 6 or 8 months animals were sacrificed. The bone surrounding the implant was examined by utilizing standard histological procedure. The material was well tolerated both in the rat and in the guinea-pig. The surface of the removed implants was examined in the SEM. No changes were observed. In both femurs of the 10 experimental and six control rats the aluminium content was determined by utilizing the atomic absorption spectroscopy method (AAS). It was found that the level of aluminium was essentially higher in the bones of the experimental animals. Therefore the safety of alumina introduction into human organisms for a long period becomes open to doubt, in spite of the favourable results of the short-term biocompatibility tests.
