Carbamazepine spherical agglomerate crystals part I. preparation and evaluation

In this study, the spherical agglomeration crystallization method was used to improve the dissolution properties of carbamazepine [CBZ]. Crystal forms 1, 2 and 3 were the agglomerates prepared by using 1, 2.8 and 5 ml of the bridging agent [chloroform], respectively, and stirred for 2 hours. The prepared CBZ crystals were evaluated by microscopic examination, particle size determination, melting point, differential scanning calorimetry [DSC], infrared spectroscopy [IR], X-ray diffraction, equilibrium solubility, dissolution study and stability study for one year. It was evident that raw CBZ belongs to modification III [CBZ [M] or beta form], whereas CBZ spherical agglomerates belongs to modification I [CBZ [T] or alpha-form]. The best results in the crystallization procedures were obtained by the use of 1 ml chloroform [bridging agent], stirring the slurry for 2 hours as well as drying in an oven at 50C for 2 days. Crystal form 1 possessed a higher solubility and a significantly higher dissolution rate compared with raw CBZ and the other crystal forms. In addition, crystal 1 possessed a high stability due to the high degree of crystalline order

Carbamazepine spherical agglomerate crystals. part II. formulation and evaluation in different dosage forms

In this study, four formulae of effervescent powder, suggested to contain 100 mg CBZ, were evaluated for their effervescence tests, humidity content as well as content uniformity. Three formulae of tablets were suggested and contained 100 mg CBZ. They were examined by weight variation test, disintegration and dissolution rate tests. Also, three formulae of capsules, containing 100 mg CBZ, were prepared and evaluated by weight variation, content uniformity and dissolution rate tests. It was evident that CBZ crystal 1 effervescent powder formula 4 and its capsule formula 3 were the best and they were subjected for a stability study at room temperature for one year. In addition, the anticonvulsant activity of the CBZ prepared formulations in mice was performed using the maximal electroshock method. For comparison, commercially available formulations; namely, Tegretol 200 tables and Tegretol suspension [100 mg/5 ml], were also evaluated

Sustained release of flufenamic acid from drug adsorbed emulsions

Sustained release flufenamic acid O/W dry adsorbed emulsions were prepared. The influence of type of oil [sesame oil and linseed oil], concentration of hydrophilic surfactant [2 and 3% of polysorbate 80] and type of hydrophilic adsorbent [Avicel PH 101 and Aerosil 200] on the tapped density [g/ml], void, flowability of flufenamic acid dry adsorbed emulsions and the percentage of drug released after 8 hours from the emulsions were evaluated using a 23 factorial design. It was found that, tapped density as well as void of flufenamic acid dry absorbed emulsion particles were affected by the type of both oil and hydrophilic adsorbent. While, the flowability of dry emulsions was only affected by the type of hydrophilic adsorbent. The most important factor that affected the drug release from dry adsorbed emulsions was the type of hydrophilic adsorbent

pharmaceutical study on topically applied tenoxicam gel

Tenoxicam transparent oil-water [TOW] gels were prepared using different oils; namely, isopropyl myristate, liquid paraffin, and myritol 318. The emulsifying agents used were Eumulgin B3, Cetiol HE, Brij 96, and Tween 80. The prepared gels were examined visually, microscopically and were photomicrographed. Conductivity, pH as well as rheological properties were determined. In vitro release studies, accelerated stability testing, and determination of anti-inflammatory activity were also performed. The results revealed that tenoxicam TOW gel prepared with liquid paraffin, Eumulgin B3, Cetiol HE combination and water [formula IV] was the most stable formula. It also affords reasonable pH, conductivity, rheological properties and in vitro drug release. The selected formula showed appreciable anti-inflammatory activity [determined by the Carrageenan induced rat paw edema] compared with a commercial piroxicam gel