This study was conducted in Lattakia Governorate (Burj Islam Village) to study the level of contamination of the greenhouses soil with the two organic phosphorous pesticides Dimethoate and Dichlorovos. The optimal wavelength was determined for the an
alysis of both pesticides using High Performance Liquid Chromatography (HPLC) technology with UV/DAD detector. According to the results, the optimal wavelength for the analysis of Dimethoate is 200 nm, while it was 195 nm for the analysis of Dichlorovos. The recovery of Dimethoate was estimated at wavelength 200 nm which was 101.33 ± 3.868 and for dichlorvos at wavelength 195 nm when it was 98.995 ± 2.078. The results also showed that the greenhouses soil were contaminated with the residues of both pesticides, Dimethoate was detected in concentrations between (0.839 - 2.668) ppm, while Dichlorovos concentrations were between (10.046 - 44.359) ppm, indicating extensive use of both especially Dichlorovos, whose concentrations were higher than Dimethoate's in the studied sites.
The purpose of this article is how to determine simultaneously the content of
some Anti-Inflammatory (NSAIDS):, Ketoprofen, Flurbiprofen, Orphenadrine
Citrate (Muscle relaxant( and Clopidogrel Bisulfate (Anti-thrombocytopenia( in
pure and pharmace
utical formulations by Reverse Phase-High performance liquid
chromatography (RP-HPLC).
A new analytical method has proposed for determination of
five synthetic colorants used in the wine industry (i.e., Tartrazine,
Brilliant Black, Sunset yellow, Brilliant Blue and Erythrosine) by
reversed-phase high-performance liquid chromatograph
y equipped
with Diode Array detector.
Experimental conditions, including spectral properties, limits
of detection and recoveries for these synthetic colorants in detail
were studied and assigned according to the statistical methods
adopted.
The possibility to develop a High-Performance Liquid
Chromatographic method was studied for simultaneous
determination of: Cu(II), Ni(II), Co(II), Hg(II) by using DTC as
reagent. The diethyldithiocorbamate Reagent was studied by
spectrophotometric Method, Unique Ionisation Constant was
determined and its value.
Tylosin and Spiramycin are medium-spectrum macrolide antibiotic used exclusively in veterinary medicine for the treatment of a wide range of infections.This research deals with the determination of optimal conditions for simultaneous separation and d
etermination of two macrolides antibiotics (Tylosin and Spyramicine), using C8 and C18 Chromatographic separation columns and doing the comparison between them in order to develop a rapid and sensitive method which can be used to measure these two compounds using High Performance Liquid Chromatography – Diode array detector (HPLC-DAD).
This study has used the gradient elution for mobile phase and revealed that the best conditions for separation and determination are conjugated with the best retention times and best areas for both studied compounds using a mobile phase consisted of an aqueous solution of anhydrated disodium Hydrogen Phosphate at pH=2.4 and an organic solution of acetonitrile with a ratio of 80:20v/v (solution A) and acetonitrile (solution B) [Na2HPO4(0.04M) pH:2.4/CAN (80:20v/v)]/ ACN, temperature 40°C for both columns, flow ratio of 1ml/min. for the mobile phase and maximum absorption wave length 280 nm, 232nm for Tylosin and Spyramicine respectively. The best peak areas are recorded as 5.759, 5.927 for Tylosin and Spyramicine 0.10ppm respectively, using C8 Chromatographic separation column in comparison with the best peak areas 4.432, 4.212 respectively at the same concentration using C18 Chromatographic separation column. It was noticed that the best retention times for Tylosin and Spyramicine were 7.013, 4.214min. respectively at concentration of 0.10ppm using C8 Chromatographic separation column in comparison with the best retention times 7.641, 5.898min. respectively at the same concentration using C18 Chromatographic separation column. The calibration curves for both separated compounds on C8 Chromatographic separation column showed a good linearity within a concentration range of 0.0010-0.10 ppm ≈ 1-100ppb at the two wave lengths λmax. = 280, 232nm respectively.
The purpose of this article is how to use HPLC technique for
quantitive analysis of cholesterol in some foods. The best conditions
are studied for this analysis including composition of mobile phase,
temperature, flow rate, the wavelength of detec
tor UV-VIS, and
acidity of mobile phase. The column used for cholesterol
determination by this method was: C18(5μm,250x4.6mm) with
injection volume of 20μL. Methanol 100% was used as mobile
phase.
spectrophotometric and chromatographic methods was used for
determination of five water-soluble vitamins, including : Thiamine
HCl (B1), Ascorbic acid (VC), Niacinamide (PP), Cyanocobalamin
(B12), Riboflavin (B2) in this research.
The conditions
of chromatographic separation were reached to the
vitamins with good resolution.
The aim of this study was to control the content of some commercial products containing amino acid (Arginine) available in the local market in addition to other products containing creatine and protein. Three methods were used for quantitative determ
ination of amino acids Kjeldahl method depending on the total content of nitrogen, assay by the visible radiation using Spectrophotometer after ninhydrin derivatization and high performance liquid chromatography with pre-column O-phtadelaldehyde derivatization using fluorescence detector. There were no significant differences in the results obtained by the three used methods. The results revealed that dietary supplements containing creatine and protein were conform to the European pharmacopoeia specifications, regarding products containing arginine used as medication and locally manufactured, they were conform to pharmacopoeia specifications while the illegal dietary supplement containing arginine were not conform.
A simple and accurate method was developed for the analysis of
carbinoxamine maleate, dextromethorphan hydrobromide and
pseudoephedrine hydrochloride content in pure form and pharmaceutical
preparations using HPLC. Analysis was conducted on a sili
ca column (6 μm)
with mobile phase consisting of ethanol – ammonium acetate (0.05 M) in rate
[85:15] respectively, and at detection wavelength of 276 nmand flow rate 1ml/ min.
Results were linear (correlation coefficient R > 0.9996) in the range of the
studied concentrations for the active materials. The relative standard
deviations (n=6) of intra and interday assay were 0.931%, 1.527% for
carbinoxamine maleate and 0.717%, 1.058 % for dextromethorphan
hydrobromide and 0.309%, 0.891% for pseudoephedrine hydrochloride,
respectively. This method, proved to be easy, precise and economical, is useful
for quality control of pharmaceutical drugs industrial samples.
The purpose of this article is how to use HPLC technique for analysis of
some vitamins. The studied vitamins are niacinamide (vit.PP), pyridoxine
hydrochloride (vit.B6), riboflavin (vit.B2) and thiamine hydrochloride (vit. B1),
which can be found
in some Syrian pharmaceutical preparations.
