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ABSTRACT: Orally disintegrating tablets (ODTs), which disintegrate rapidly (<1 min) in the mouth and do not require water for administration, have become a very popular dosage form. The study aims to develop a simple and inexpensive method of manufacturing ODTs of a sparingly water-soluble drug, Dextromethorphan hydrobromide. Two factors, three levels (3(2)) full factorial design was used to optimize the diluent, microcrystalline cellulose (X(1)) and superdisintegrant, croscarmellose sodium (X(2)) concentrations. Disintegration time, hardness and T(50) values for all the formulations varied from 12.5 to 152.6 s, 3.58 to 4.92 kp and 0.8 to 2.8 min, respectively. The results indicated that the selected variables have a strong influence on disintegration time, hardness and T(50) of the ODTs. The manufactured ODTs formula composed of 30% microcrystalline cellulose in combination with 3% croscarmellose sodium was chosen as optimized formula, as it showed the lowest disintegration time (12.5 ± 1.22 s), low T(50) (0.8 min.) and hard tablets (4.92 ± 0.28 kp) amongst other tested ODTs formulations. Hardness of DM ODTs was not affected by changing the type of superdisintegrant and lubricant. The disintegration time was significantly (p < 0.05) increased by using sodium starch glycolate instead of croscarmellose sodium.
Pharmaceutical Development and Technology 08/2012; · 1.36 Impact Factor
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ABSTRACT: Mesoporous silica shell based nanoarchitectures as hollow, solid and rattle type core-mesoporous shell have recently received attentions for their versatile applications in drug delivery, and drug controlled release. Recently we have developed double mesoporous core-shell silica nanospheres by anionic surfactant. However, in this work shell thickness, BET surface area, pore volume and pore size can be tuned by varying synthetic affected accordingly. Double mesoporous core-shell nanospheres were characterized by small angle X-ray Scattering (SAXS), transmission electron microscopy (TEM), and N 2 adsorption–desorption analysis. In that regards, variation of synthetic parameters lead to increment of shell thickness and pore volume from 28 nm to 55 nm and 0.301 to 0.371 cm 3 /g, respectively, which finally caused a drug encapsulation efficiency to be promoted from 10.71 to 20.8%. Furthermore, the drug encapsulation efficiency and release rate were found to be release rate tended to be more controlled with increasing the shell thickness and pore volume.
Digest Journal of Nanomaterials and Biostructures 05/2012; 7:447-458. · 1.20 Impact Factor
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ABSTRACT: In this work, we demonstrate a simple two-pot approach to double mesoporous core-shell silica spheres (DMCSSs) with uniform size of 245-790 nm, shell thickness of 41-80 nm and surface area and total pore volume of 141-618 m(2) g(-1) and 0.14-0.585 cc g(-1), respectively. First, solid silica spherical particles were synthesized by the Stöber method and used as a core. Second, a mesoporous shell could be formed around the silica cores by using an anionic surfactant and a co-structure directing agent. It was found that mesopores can be anchored within dense silica cores during mesoporous silica shell formation, synchronously the base group with surfactant assistant can etch the dense silica cores to re-organize new mesostructure, so that double mesoporous core-shell silica sphere (DMCSS) structure can be obtained by a single surfactant-templating step. The spherical size and porosity of the silica cores of DMCSS together with shell thickness can be tuned by controlling Stöber parameters, including the concentrations of ammonia, solvent and tetraethoxysilane and the reaction time. DMCSS were loaded with ketoprofen and thymoquinone, which are an anti-inflammatory and a potential novel anti-cancer drug, respectively. Both drugs showed controlled release behavior from the pores of DMCSS. Drug uptakes within DMCSS were ~27 and 81 wt.% for ketoprofen and thymoquinone, respectively. Furthermore, DMCSS loaded with thymoquinone was more effective in inducing cancer cell apoptosis than uncontained thymoquinone, because of the slow release of the drug from the mesoporous structure.
Journal of Colloid and Interface Science 04/2012; 378(1):83-92. · 3.07 Impact Factor
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ABSTRACT: In this work, mesoporous shells were constructed on solid silica cores by employing anionic surfactante. A co-structure directing agent (CSDA) has assisted the electrostatic interaction between negatively charged silica particles and the negatively charged surfactant molecules. Synthetic parameters such as reaction time and temperature had a significant impact on the formation of mesoporous silica shelld and their textural properties such as surface area and pore volume. Core-mesoporous shell silica spheres were characterized by small angle X-ray scattering, transmission electron microscopy, and N(2) adsorption–desorption analysis. The synthesized particles have a uniformly mesoporous shell of 34–65 nm and possess a surface area of ca. 7–324 m2/g, and pore volume of ca. 0.008–0.261 cc/g. The core-mesoporous shell silica spheres were loaded with ketoprofen drug molecules. The in vitro drug release study suggested that core-mesoporous shell silica spheres are a suitable nanocarrier for drug molecules offering the possibility of having control over their release rate.
Molecules 01/2012; 17(11):13199-210. · 2.39 Impact Factor
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ABSTRACT: In this communication, we report the fabrication of silica nanospheres with a double mesoporous core-shell structure by a one-templating step two-pot synthesis route using an anionic surfactant.
Chemical Communications 09/2010; 46(35):6482-4. · 6.17 Impact Factor
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ABSTRACT: This study aimed at preparation of a sustained-release steroidal treatment for chronic inflammatory conditions, such as rheumatoid arthritis. To achieve such a goal, biodegradable poly-lactide-co-glycolide prednisolone-loaded microspheres were prepared using o/w emulsion solvent evaporation method. Formulation parameters were adjusted so as to optimize the microsphere characteristics. The prepared microspheres exhibited smooth and intact surfaces, with average size range not exceeding 65 microm. The encapsulation efficiency percent of most microsphere formulations fell within the range of 25-68%. Drug release from these microspheres took place over 4 weeks, with near-to-zero-order patterns. Two successful formulations were chosen for the treatment of unilateral arthritis, induced in mice using Freund's complete adjuvant (FCA). Inflammatory signs of adjuvant arthritis included severe swelling of the FCA-injected limbs, in addition to many histopathological lesions. These included inflammatory cell infiltration, synovial hyperplasia, cartilage, and bone erosion. Parenteral administration of the selected formulae dramatically reduced the swelling of the FCA-injected limbs. In addition, histological examination revealed that the microsphere treatment protocol efficiently protected cartilages and bones of mice, injected with FCA initial and booster doses, from erosion. These results could not be achieved by a single prednisolone dose of 5 mg/kg.
AAPS PharmSciTech 06/2010; 11(2):859-69. · 1.43 Impact Factor
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Mohamed Abbas Ibrahim
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ABSTRACT: Insulin-loaded PEG2-PLA40 and PEG5-PLA20 microspheres containing 5% bovine insulin were manufactured using single emulsion and w/o/w multiple emulsion-solvent evaporation techniques. Microspheres were characterized for their insulin encapsulation efficiency and release characteristics in phosphate-buffered saline (PBS) at pH 7.4 and 37 ÂC. Moreover, the stability of the peptide during 18 days of release was evaluated using HPLC and HPLC-MS techniques. The results showed that the loading efficiencies were higher in case of insulin loaded PEG2-PLA40 and PEG5-PLA20 microspheres prepared by single emulsion emulsion-solvent evaporation technique. Insulin release was characterized by an initial burst, which was attributed to the amount of protein located on or close to the microsphere surface. The total ion chromatogram (TIC) of insulin samples extracted after 6, 12 and 18 days of PEG2-PLA40 microspheres erosion showed that insulin was intact inside the eroding microspheres. In addition, only small amounts of protein undergo degradation under these conditions (only 11.69% Â 1.13 of the initially loaded insulin loading were detected as degradation products after 18 days. Mass spectra recorded at these retention times confirmed the presence of insulin with a molar mass of 5734 Da and other two products of molar masses of 5587 Da and 5487 Da.
Scientia Pharmaceutica 01/2010; 78(3):493-505.
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ABSTRACT: In recent years, the acylation of peptides during the erosion of poly(lactic acid) and poly(lactic-co-glycolic acid) microspheres has been described in the literature. To investigate whether insulin is prone to the covalent attachment of lactic or glycolic acid, insulin-loaded PLA and PLGA microspheres containing 5% bovine insulin were manufactured using a w/o/w multiple emulsion-solvent evaporation technique. Microspheres were characterized for their insulin encapsulation efficiency and release characteristics in phosphate-buffered saline (PBS) at pH 7.4 and 37 degrees C. Moreover, the stability of the peptide during 18 days of release was evaluated using HPLC and HPLC-MS techniques. The results showed that the insulin loading efficiencies of PLA and PLGA microspheres were 75.18% and 79.63%, respectively. The microspheres were spherical with relatively porous surfaces with an average diameter of 40 and 53 mum, respectively. Insulin release from the microspheres was characterized by an initial burst, which was attributed to the amount of protein located on or close to the microsphere surface. The total ion chromatogram (TIC) of insulin samples extracted after 18 days of erosion in phosphate buffer pH 7.4 at 37 degrees C revealed that deamidation was the major mechanism of instability. Surprisingly, no acylation products were found. Control experiments in concentrated lactic acid solutions confirmed a minimal reactivity of the peptide under these conditions.
Journal of Controlled Release 10/2005; 106(3):241-52. · 5.73 Impact Factor
