[Determination of the crystal lengths of recrystallized amoxicillin trihydrate at different pH values using fluorescence microscope and NIR spectroscopy and study their effects on increasing the dissolution rate]

The purpose of the study in this research is to investigate some physicochemical properties of amoxicillin trihydrate which has an important role in increasing the dissolution rate. Flowability, particle size distribution, length of the raw material needle crystals and pH values of raw material solutions 2mg/ml had been studied for amoxicillin trihydrate obtained from different suppliers. Flowability had been studied based on Compressibility Index and Hausner ratio. Particle size distribution and crystal shape had been determined using sieves, scanning fluorescence microscope and near infrared spectroscopy, respectively. The dissolution rate of different particle sizes of the raw material obtained by sieves and prepared in hard gelatin capsules as a single dose of 250 mg was evaluated using dissolution tester [I] and samples were analyzed using U.V spectrophotometer at a wavelength of 272 nm. The study had shown that the dissolution rates of amoxicillin trihydrate increased as the particle size decreased complying to Noyes-Whitney equation for range of particle sizes 0.063-1 mm. This equation can't be applied successfully for particles of sizes less than 63 micro m. The results had also shown that the dissolution rate for the same particle size of amoxicillin trihydrate increased as the length of the raw material needle crystal increased from 2.2 micro m to 8.5 micro m. Recrystallization of amoxicillin trihydrate had been studied at different pH values [pH=2, 4, 7, 9, 11]. Amoxicillin trihydrate samples recrystallized at pH values pH=7, 9, 11 appear to have superior physicochemical properties to the original amoxicillin trihydrate samples in purity, needle crystal length and dissolution rate, but the powder flowability of amoxicillin trihydrate samples recrystallized at p11=11 was very bad compared to other samples

[Accelerated stability study of oral lyophilizates containing a non steroidal anti-inflammatory drug]

The objective of the study was to estimate the accelerated stability of oral lyophilizates containing diclofenac sodium. Three batches of oral lyophilizates were prepared, packed and stored under the conditions recommended by ICH. Oral lyophilizates were analyzed at the time 0, 3 and 6 months. At every point, it has been determined the visual aspect, hardness, disintegration time, residual humidity, drug releases and thermal analysis. Drug content was determined by High performance liquid chromatography [HPLC]. Stability results showed increasing in the residual humidity and hardness without any effect on the disintegration time, while results of drug release studies showed the same profile of initial drug release. HPLC results confirmed that diclofenac sodium is stable in oral lyophilizates. The results of DSC confirmed the maintenance of crystalline state of mannitol and diclofenac sodium in the oral lyophilizates before and after 6 months of storage. The results of FTIR showed that there isn't any iteraction between the drug and the excipients

[Separation and calibration of some anthraquinones in the types of aloe which grow in Syria]

Aloe is one of the most important medicinal plants at the present time, which entered to Syria since a long time. Genus Aloe has about four hundred species. In this research species in Syria were classified, which their number is six. Aloin and Aloe-emodin were calibrate in the six species that are the most important Anthraquinones. It was noted that there is not Aloe-emodin in the six species, but there is Aloin only in five types