1,721,003 research outputs found
HPLC and GC-MS detection of compounds released to mineral waters stored in plastic bottles of PET and PVC
No full textThe migration of certain compds. from PET [poly(ethylene terephthalate)] and poly(vinyl chloride) bottles to waters was studied by HPLC with UV detection after extn. with di-Et ether. Compds. in mineral waters were identified by gas chromatog.-mass spectrometry (GC-MS). Erucamide, from PET bottles, was quant. detd. in some mineral waters. Two other compds., also detected in mineral waters stored in PET, were identified as low-mol.-wt. cyclic oligomers produced during the PET polymn. process
Development and Validation of a MEKC Method for Determination of Nitrogen-Containing Drugs in Pharmaceutical Preparations
No full textA fast and accurate micellar electrokinetic capillary chromatography method was developed for quality control of pharmaceutical preparations containing cold remedies as acetaminophen, salicylamide, caffeine, phenylephrine, pseudoephedrine, norephedrine and chlorpheniramine. The method optimization was realized on a Beckman P/ACE System MDQ instrument. The baseline separation of seven analytes was performed in an uncoated fused silica capillary internal diameter (ID)=50 μm using tris-borate (20 mM, pH=8.5) containing sodium dodecyl sulphate 30 mM BGE. On line-UV detection at 214 nm was performed and the applied voltage was 10 kV. The operating temperature was 25°C. After experimental conditions optimization, the proposed method was validated. The evaluated parameters were: precision of migration time and of corrected peak area ratio, linearity range, limit of detection, limit of quantification, accuracy (recovery), ruggedness and applicability. The method was then successfully applied for the analysis of three pharmaceutical preparations containing some of the analytes listed before
Determination of phenolic acids in wine by high-performance liquid chromatography with a microbore column
No full textA method for the extraction and separation of the non-volatile phenolic acids of wine is described. The extracts are analysed by HPLC with a microbe column and UV detection. The free phenolic acids and depsides in different wine samples were identified and determine
RAPID ANALYSIS OF MELATONIN IN PHARMACEUTICAL TABLETS BY CAPILLARY ELECTROPHORESIS WITH UV DETECTION
No full textMelatonin content in pharmaceutical products was quantitatively determined by capillary electrophoresis within 4 min. Sample preparation required the simple dissolution in water and filtration.An internal standard was used, a linear relationship between malatonine concentr. and R(melatonin corrected peak area/I.S. corrected area was obtained. Separations were carried out in a coated capillaries in borate running buffer. The method showed an high precision with a RSD for migration time of 0.3% for intra-day and 1.4%for inter-day measures (n=48). For the R parameter RSD was 2.9% and refers to seven consecutive runs of the same sample on the same day. Two commercially available pharmaceutical products containing melatonin were analysed. The method offers an easy and accurate routin option
Determination of cow milk in ewe milk and cheese by capillary electrophoresis of the whey protein fractions
No full textCapillary Electrophoresis was successfully applied to detect and determine the percentage of cow milk used in adulteration of ewe milk products. The sepatation of the whey proteins was achieved in an 80mM pH 9.2 borate buffer, the only component of BGE. Determination of the percentage of cow milk was based on the ratio of the corrected peak area of cow beta-lactoglobulin to the corrected peak area of a ewe protein hence eliminating the need of the internal standard. The use of methyl silanized capillaries and of proper washing after every run eliminated wall-adsorption phenomena and allowed good repeatability for migration time (RSD% 0.5) and and for ration of the corrected peak areas (RSD% 3.0). A preconcentration step made possible to detect small quantities of cow milk , up to0.5% in milk mixtures and up to 2% in cheeses
- …
