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Abstract. The aim of the present study was to enhance the dissolution rate of meloxicam (MLX), a practically water-insoluble drug by preparation of solid dispersion using a hydrophilic polymer, poloxamer 188 (PXM). The kneading technique was used to prepare solid dispersions. A 3 2 full factorial design approach was used for optimization wherein the drug, polymer ratio (X 1 ), and the kneading time (X 2 ) were selected as independent variables and the dissolution efficiency at 60 min (%DE 60 ) and yield percent were selected as the dependent variable. Multiple linear regression analysis revealed that for obtaining higher dissolution of MLX from PXM solid dispersions, a high level of X 1 and a high level of X 2 were suitable. The use of a factorial design approach helped in optimization of the preparation and formulation of solid dispersion. The optimized formula was characterized by solubility studies, angle of repose, and contact angle; Fourier transform infrared spectroscopy, differential scanning calorimetry, x-ray diffraction studies, and scanning electron microscopy demonstrated that enhanced dissolution of MLX from solid dispersion might be due to a decrease in the crystallinity of MLX and PXM. Analysis of dissolution data of optimized formula indicated the best fitting with KorsemeyerPeppas model and the drug release kinetics as Fickian diffusion. In conclusion, dissolution enhancement of MLX was obtained by preparing its solid dispersion with PXM using kneading technique.

Abstract. Diazepam is one of the most prescribed benzodiazepines. The purpose of the present research was to optimize the formulation of orodispersible tablets of diazepam. Orodispersible tablets of diazepam were prepared using different types of superdisintegrants (Ac-Di-Sol, sodium starch glycolate, and crospovidone (CP)) and different types of subliming agents (camphor and ammonium bicarbonate (AB)) at different concentrations and two methods of tablets preparations (wet granulation and direct compression methods). The formulations were evaluated for flow properties, wetting time, hardness, friability, content uniformity, in vivo disintegration time (DT), release profiles, and buccal absorption tests. All formulations showed satisfactory mechanical strength except formula F5 which contains camphor and formula F9 which is prepared by direct compression method. The results revealed that the tablets containing CP as a superdisintegrant have good dissolution profile with shortest DT. The optimized formula F7 is prepared using 10% CP as a superdisintegrant and 20% AB as a subliming agent by wet granulation method which shows the shortest DT and good dissolution profile with acceptable stability. This study helps in revealing the effect of formulation processing variables on tablet properties. It can be concluded that the orodispersible tablets of diazepam with better biopharmaceutical properties than conventional tablets could be obtained using formula F7.

CD-nanosponges were prepared by crosslinking B-CD with diphenylcarbonate (DPC) using ultrasound assisted technique. 5-FU was incorporated with NS by freeze drying, and the phase solubility study, complexation efficiency (CE) entrapment efficiency were performed. Also, the particle morphology was studied using SEM and AFM. The in-vitro release of 5-FU from the prepared nanosponges was carried out in 0.1N HCl. 5-FU nanosponges particle size was in the nano size. The optimum formula showed a particle size of (405.46±30) nm, with a polydispersity index (PDI) (0.328±0.002) and a negative zeta potential (-18.75±1.8). Also the drug entrapment efficiency varied with the CD: DPC molar ratio from 15.6 % to 30%. The SEM and AFM showed crystalline and porous nature of the nanosponges. The in vitro drug release study of the selected formula 5-FUNS2 exhibited the fastest dissolution rate which is 56% in the first hr. Different molar ratios of (cyclodextrin to crosslinker) (CD: DPC) has a proficient effect on complexation efficiency (CE), apparent stability constant (Kst) and entrapment efficiency of 5-FU. 5-FUNS2 with (1:4) molar ratio showed the best result of CE, Kst and entrapment efficiency. 5-FUNS2 gave a higher release rate than the 5-FU-BCD inclusion complex and 5-FU solution. Surface morphology of the prepared nanosponges by SEM, AFM indicate that nanosized and highly porous nanosponges was obtained. The overall results suggest that cyclodextrin nanosponges could be a promising 5-FU delivery system utilizing the suitable formula.

Folic acid and multivitamin tablets containing Aspergillus flavus Penicillia spp. and Cladosporia spores were prepared at a compression pressure of 148 MN/m2 and stored at 35°C under different relative  humidifies (75,85, and 95)% within air tight containers, to study the effect of storage condition on them, as well as ,the estimation of the microbial level of the raw materials intended to be used in the two kinds of tablets . Result showed that some raw materials derived from natural origin were heavily contaminated with microorganism compared to that of synthetic origin ,the results also indicated the effect of relative humidity , types of fungal spore , and the hygroscopic nature of exicpient upon survival. Multivitamin tablets showed more survival than folic acid tablets and this is due to the presence of more nutrients. No aflatoxin was obtained from both multivitamin and folic tablets at 35°C temperature; this is due to the temperature which is not an optimum temperature for aflatoxin B1 production. Key words: Storage conditions of tablet, fungal spores