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Charles Univerzity in Prague, Faculty of Pharmacy in Hradec Králové Department of Pharmaceutical technology Student: Mgr. Stanislav Gregor Supervisor: Doc. RNDr. Milan Řehula, CSc. Physico-chemical characteritazion of microcrystalline celluloses Microcrystalline cellulose is very important pharmaceutical excipient. The aim of the study was to evaluate the different types by using physico-chemical charakteristics. Particle size was evaluated by optical microscopy. The flow properties were evaluated by flowability and by the angle of repose. Bulk and tapped properties were evaluated by bulk and tap density and by compressibility index. Temperatute and heat of fusion, glass transitive temperature and specific heat improvers were evaluated by DSC. Compaction process was evaluated by compaction equations, stress relaxation test and record the force-displacement. The compressed tablets were evaluated by kinetics crushing tablets and had fixed radial strength. Particle sizes correspond to the declared values stated by the manufacturer. The largest deviation was found for Avicel PH-200 (difference 20,0 mm). With increasing particle size reduces fiction between particles and increases the flowability. The tapped density is higher than the bulk density and the copies. From the results of three- exponential... |
