Ali M. Qaisi

A bioequivalence study of two brands of doxycycline capsules

Abstract Bioequivalence of two preparations of doxycycline (Doxydar ™ 100-mg capsules and Vibramycin ™ 100-mg capsules) were compared in a two-way crossover study. Pharmacokinetic parameters were determined for both formulations, including area under the concentration-time curve, mean maximum plasma concentration, time to maximum concentration, half-life, and the terminal rate of elimination. Statistical analysis revealed that differences between the two formulations were not statistically significant. Quality control data, including assay and disintegration, indicated that both products met the in-house specifications. It is concluded that Doxydar 100 mg is bioequivalent to Vibramycin 100 mg.

A comparative single-dose bioequivalence study of two brands of glipizide

Abstract The purpose of this study was to compare the bioavailability and pharmacokinetic properties of two glipizide formulations (Sucrazide ® versus Minidiad ® ). Twenty healthy male volunteers were given a 5-mg tablet of each product in a 12-hour, two-way crossover study (1-week washout period between formulations). Blood samples were collected 13 times over 12 hours following oral administratin of each drug and plasma levels of glipizide were determined by using a modified high-performance liquid chromatographic method. There were no significant differences in oral absorption, area under the concentration-time curve, mean maximum plasma concentration, time to maximum concentration, half-life, and elimination constants between Sucrazide and Minidiab. In addition, quality control data (including assay, dis-integration, and dissolution (tests) indicated that both brands passed both US and British Pharmacopeia standards. In conclusion, our results demonstrated that Sucrazide 5-mg tablets are bioequivalent to Minidiab 5-mg tablets.

Simultaneous Determination of Cetirizine and Pseudoephedrine Combined in Tablet Dosage Form by High Performance Liquid Chromatography

This study develops and validates an efficient, sensitive and simple method for the simultaneous determination of cetirizinedihydrochloride and pseudoephedrinecombined in tablet dosage form by high performance liquid chromatography (HPLC) with an ultraviolet (UV) detector.The validation of this method was carried out according to ICH and USP guidelines. In this study, the mobile phase used wasacetonitrile: water (530:470 (v/v)) with 200mg sodium heptane sulfonic acid and the pH value was adjusted to 2.5 with sulfuric acid. The limit of detection and quantification for cetirizinedihydrochloride were 0.805 and 2.685 µg/mL,respectively,and the limit of detection and quantification for pseudoephedrinewere17.976 and 59.921 µg/mL, respectively. The linearity was studied in the concentration range of 12.2 and 36.5 µg/mL forcetirizinedihydrochloride and 295.91 and 861.73 µg/mL for pseudoephedrine. The recovered amounts of cetirizinedihydrochloride and pseudoephedrinewere98.2% -102.9% and99.5%- 102.4%, respectively.

Simultaneous Determination and Stability Assessment of Metformin and Sitagliptin in Pharmaceutical Form by High Performance Liquid Chromatography = التحديد المتزامن للميتفورمين والسيتاجلبتين في الشكل الصيدلاني باستخدام الكروماتوغرافيا السائلة عالية الأداء

A simple, rapid and highly selective chromatographic procedure is developed for simultaneous quantification of Metformin and Sitagliptinin tablet formulation. The active ingredients are separated using dihydrogen phosphate buffer (pH 6.00)/acetonitrile mobile phase, flow rate 1.0 mL.min-1, and with DAD detection at 218 nm. The stability and assay separation process are accomplished in 9.0 min with high resolution. The method is precise and accurate. A wide dynamic ranges (1.0-15.0) and (2.0-150.0) mg/L for Metformin and Sitagliptin, respectively, is employed. Both drugs are quantified down to 0.1 and 1.0 mg/L for Metformin and Sitagliptin, respectively, which indicates the high sensitivity of the procedure. Finally, the stability-indicating capability of the procedure is accomplished for tablet formulation (50 mg Metformin and 500 Sitagliptin), and the results indicated that Metformin is unstable to UV and H2O2 with degradation higher than 30.0%. Furthermore, Sitagliptin is unstable at acidic, basic, and oxidation environments

Direct conversion of an ortho-allylphenol into a chlorosulfonyl-3-methyl-1,2-benzoxathiin 2,2-dioxide

A one-pot synthesis of methyl 6-chlorosulfonyl-3-methyl-1,2-benzoxathiin-8-carboxylate 2,2- dioxide (9), characterized as its 6-(4-methylpiperazin-1-yl)sulfonyl derivative 10, is achieved via direct reaction of methyl 3-allylsalicylate (1) with chlorosulfonic acid at −7°C. The latter reagent converts methyl 2-methyl-2,3-dihydrobenzofuran-7-carboxylate (3) into the respective 5-chlorosulfonyl derivative 7 (identified as its 5-(4-methylpiperazin-1-yl)sulfonyl derivative 8), while contrary to literature reports, the aromatic δ -sultones 9, 10 (anticipated to be produced from 3) were not detected.