King Faisal Specialist Hospital & Research Centre

About: King Faisal Specialist Hospital & Research Centre is a healthcare organization based out in Riyadh, Saudi Arabia. It is known for research contribution in the topics: Detection limit & High-performance liquid chromatography. The organization has 58 authors who have published 157 publications receiving 3527 citations.

Chiral resolution of two potential aromatase inhibitors on cellulose tris (4-methyl benzoate) and cellulose tris (3,5-dimethylphenyl carbamate) chiral stationary phases

Abstract: The chiral resolution of 1-[(benzofuran-2-yl)-5-nitrophenylmethyl] tetrazole (I) and 1-[(benzofuran-2-yl)-5-bromophenylmethyl] tetrazole (II), the novel aromatase inhibitors, has been achieved on Chiracel OD, Chiracel OD-RH columns which are coated with cellulose [tris (3,5-dimethylphenyl carbamate)]and Chiracel OJ-R column coated with cellulose [tris(4-methyl benzoate)]. The mobile phases used were hexane-2-propanol (95:5) on Chiracel OD and water-acetonitrile(45:55) on Chiracel OD-RH and Chiracel OJ-R columns respectively. Compound I has been resolved on Chiracel OD(α = 1.30 and Rs = 3.13) and OD-RH (α = 1.15 and Rs = 1.20)columns while compound II has been resolved on OJ-R(α = 1.31 and Rs = 1.80) column only. The effect of acetonitrile concentration in water-acetonitrile mobile phase was studied on the retention and resolution of both compounds.

Voltammetric determination of coenzyme q10 at a solid glassy carbon electrode

Abstract: This paper reports a simple, sensitive, and accurate voltammetric method for the coenzyme Q10 electroanalytical determination on a glassy carbon electrode (GCE) from commercially available capsules, compared with a UV-VIS spectrophotometric method. Cyclic (CV), linear sweep (LSV), and square-wave (SWV) voltammetry on GCE was employed to explore the coenzyme Q10 behaviour, using as supporting electrolyte, 0.12 M H2SO4 (in methanol) in hexane/methanol (1:2 vol.) mixture. The voltammograms showed the characteristic reduction peaks at potential values in the range of 0.190– 0.300 V vs. Ag/AgCl, depending on the technique that was used. A linear dependence of the reduction peak height on the analyte concentration was obtained using LSV and SWV techniques in the domains 5 × 10−6 −7 × 10−4 mol L−1,and 5 × 10−7 −7 × 10−4 mol L−1 coenzyme Q10 concentration. The detection limit was 10−7 mol L−1 for SWV. The coenzyme Q10 determination from commercially available capsules required four consecutive steps of compound e...

Biotin dissolution from pharmaceutical dosage forms using an automated HPLC system

Abstract: A novel, rapid, accurate, and sensitive automated high‐performance liquid chromatographic assay was developed to determine biotin (BI) in pharmaceutical dosage forms and to follow its dissolution pattern. An efficient separation of BI was performed using a stainless steel Supelcosil LC‐18 column (25 cm × 4.6 mm; 5 µm particle size) preceded by a Sentry guard column. The mobile phase consisted of an 80% aqueous solution (pH 2.5 adjusted with phosphoric acid) containing 20% acetonitrile delivered at a flow rate of 1.5 mL/min. The compound of interest was detected using a photodiode array detector at 190 nm. Under these conditions, the assay run time was 6 min since the retention time of BI was 3.8 ± 0.2 min. The detector response was linear for BI in alkaline solution (r > 0.999) in the range of 0.01–2.00 µg/mL. The detection and the quantification limits for BI were 0.005 and 0.01 µg/mL, respectively. The dissolution data showed RSD% of 3.6–12.7% for all BI determined concentrations. No interferen...

ENANTIOMERIC SEPARATION OF AMINOGLUTETHIMIDE, ACETYL AMINOGLUTETHIMIDE, AND DANSYL AMINOGLUTETHIMIDE BY TLC WITH β-CYCLODEXTRIN AND DERIVATIVES AS MOBILE PHASE ADDITIVES

Abstract: Racemic aminoglutethimide and acetylaminoglutethimide were resolved on a fluorescent Silica gel 60A TLC plate using 30% hydroxy trimethylpropylammonium-β-cyclodextrin with methanol (50:50v/v) as the mobile phase. Also, the resolution of the enantiomers of aminoglutethimide as dansyl derivatives were investigated on reversed phase TLC using a mobile phase consisting of a β-cyclodextrin solution (0.05 M saturated with urea), or 15% (carboxymethyl-β-cyclodextrin) solution with methanol (65:35v/v). Enantiomeric resolution was found to be highly dependent on mobile phase composition. The effect of the type and amount of organic modifier as well as the concentration of β-CD derivative, and the pH of the mobile phase on resolution were studied. Three types of maltodextrins failed to show resolution for any of the racemic compounds studied.

A validated method for analysis of chromium picolinate in nutraceuticals by reversed phase high performance liquid chromatography.

Abstract: A validated high performance liquid chromatographic method was developed for the determination of chromium picolinate in pharmaceutical dosage forms. The analysis was performed at room temperature using a reversed-phase Supelcosil LC-18 (250 x 4.6 mm, 5 microm) column. The mobile phase consisted of acetonitrile:water (40:60 v/v) at a fl ow rate of 0.8 mL/min. The UV-detector was set at 264 nm. The developed method showed a good linear relationship in the concentration range from 0.125 to 12.5 microg/mL with a correlation coefficient from 0.999. The limit of detection and limit of quanti fi cation were 0.091 and 0.181 microg/mL, respectively.