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Jeddah, Saudi Arabia

Ashour S.,University of Aleppo | Bayram R.,Batterjee Medical College
Spectrochimica Acta - Part A: Molecular and Biomolecular Spectroscopy

New, accurate, sensitive and reliable kinetic spectrophotometric method for the assay of moxifloxacin hydrochloride (MOXF) in pure form and pharmaceutical formulations has been developed. The method involves the oxidative coupling reaction of MOXF with 3-methyl-2-benzothiazolinone hydrazone hydrochloride monohydrate (MBTH) in the presence of Ce(IV) in an acidic medium to form colored product with lambda max at 623 and 660 nm. The reaction is followed spectrophotometrically by measuring the increase in absorbance at 623 nm as a function of time. The initial rate and fixed time methods were adopted for constructing the calibration curves. The linearity range was found to be 1.89-40.0 μg mL-1 for initial rate and fixed time methods. The limit of detection for initial rate and fixed time methods is 0.644 and 0.043 μg mL-1, respectively. Molar absorptivity for the method was found to be 0.89 × 104 L mol-1 cm-1. Statistical treatment of the experimental results indicates that the methods are precise and accurate. The proposed method has been applied successfully for the estimation of moxifloxacin hydrochloride in tablet dosage form with no interference from the excipients. The results are compared with the official method. © 2015 Elsevier B.V. All rights reserved. Source

Abdulra'Uf L.B.,University of Malaya | Abdulra'Uf L.B.,Kwara State University | Sirhan A.Y.,Batterjee Medical College | Tan G.H.,University of Malaya
Journal of AOAC International

Sample preparation has been identified as the most important step in analytical chemistry and has been tagged as the bottleneck of analytical methodology. The current trend is aimed at developing cost-effective, miniaturized, simplified, and environmentally friendly sample preparation techniques. The fundamentals and applications of multivariate statistical techniques for the optimization of microextraction sample preparation and chromatographic analysis of pesticide residues are described in this review. The use of Placket-Burman, Doehlert matrix, and Box-Behnken designs are discussed. As observed in this review, a number of analytical chemists have combined chemometrics and microextraction techniques, which has helped to streamline sample preparation and improve sample throughput. Source

Anwar M.M.,National Research Center of Egypt | El-Haggar R.S.,Helwan University | El-Haggar R.S.,Batterjee Medical College | Zaghary W.A.,Helwan University | Zaghary W.A.,King Saud University
Profiles of Drug Substances, Excipients and Related Methodology

Salmeterol xinafoate is a potent and a long-acting β2-adrenoceptor agonist. It is prescribed for the treatment of severe persistent asthma and chronic obstructive pulmonary disease. Different methods were used to prepare (R)-(-)-salmeterol such as: mixing a sample of 4-benzyloxy-3-hydroxymethyl-ω-bromoacetophenone with sodium lauryl sulfate and the mixture was added to the microbial culture of Rhodotorula rubra, treatment of p-hydroxyacetophenone with Eschenmoser's salt and carbonate exchange resin followed by a sequence of supported reagents and scavenging agents or via Rh-catalyzed asymmetric transfer hydrogenation. The enantioselective synthesis of (S)-salmeterol was achieved via asymmetric reduction of the azidoketone 4 by Pichia angusta yeast. Physical characteristics of salmeterol xinafoate were confirmed via: X-ray powder diffraction pattern, thermal analysis and UV, vibrational, nuclear magnetic resonance, and mass spectroscopical data. Initial improvement in asthma control may occur within 30min following oral inhalation of salmeterol in fixed combination with fluticasone propionate. Clinically important improvements are maintained for up to 12h in most patients. It is extensively metabolized in the liver by hydroxylation, thus increased plasma concentrations may occur in patients with hepatic impairment. © 2015 Elsevier Inc. Source

Alfaris E.,King Saud University | Naeem N.,Batterjee Medical College | Irfan F.,King Saud University | Qureshi R.,King Saud University | And 4 more authors.
Journal of Dental Education

Long training workshops on the writing of exam questions have been shown to be effective; however, the effectiveness of short workshops needs to be demonstrated. The aim of this study was to evaluate the impact of a one-day, seven-hour faculty development workshop at the College of Dentistry, King Saud University, Saudi Arabia, on the quality of multiple-choice questions (MCQs). Kirkpatrick's four-level evaluation model was used. Participants' satisfaction (Kirkpatrick's Level 1) was evaluated with a post-workshop questionnaire. A quasi-experimental, randomized separate sample, pretest-posttest design was used to assess the learning effect (Kirkpatrick's Level 2). To evaluate transfer of learning to practice (Kirkpatrick's Level 3), MCQs created by ten faculty members as a result of the training were assessed. To assess Kirkpatrick's Level 4 regarding institutional change, interviews with three key leaders of the school were conducted, coded, and analyzed. A total of 72 course directors were invited to and attended some part of the workshop; all 52 who attended the entire workshop completed the satisfaction form; and 22 of the 36 participants in the experimental group completed the posttest. The results showed that all 52 participants were highly satisfied with the workshop, and significant positive changes were found in the faculty members' knowledge and the quality of their MCQs with effect sizes of 0.7 and 0.28, respectively. At the institutional level, the interviews demonstrated positive structural changes in the school's assessment system. Overall, this one-day item-writing faculty workshop resulted in positive changes at all four of Kirkpatrick's levels; these effects suggest that even a short training session can improve a dental school's assessment of its students. Source

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