High-performance liquid-chromatographic method compared with a modified radioimmunoassay of cotinine in plasma

1991 ◽  
Vol 37 (11) ◽  
pp. 1989-1993 ◽  
Author(s):  
S L Perkins ◽  
J F Livesey ◽  
E A Escares ◽  
J M Belcher ◽  
D K Dudley
Keyword(s):  
High Performance ◽  
Solid Phase ◽  
Plasma Concentrations ◽  
Potassium Phosphate ◽  
High Performance Liquid Chromatographic ◽  
Reversed Phase ◽  
Liquid Chromatographic Method ◽  
Assay Precision ◽  
Liquid Chromatographic ◽  
Interassay Precision

Abstract Cotinine is a sensitive and specific biochemical marker of exposure to cigarette smoke. We describe a simple solid-phase extraction of cotinine from plasma before quantification by HPLC. Extraction recovery was 97.9% +/- 11.0% for plasma concentrations of 5-400 micrograms/L. Baseline separation of cotinine and caffeine was achieved within 11 min of injection onto a C18 reversed-phase column. The mobile phase was citric acid/dibasic potassium phosphate (30 mmol/L each, pH 6.0) containing 100 mL of acetonitrile per liter. Within-day and day-to-day precision (CV) were 4.7% and 8.4%, respectively. We also describe a modification of the Nicotine Metabolite RIA kit (Diagnostic Products Corp.) for quantifying cotinine in plasma. Recovery of cotinine from supplemented plasma was within 10% of the expected value with this RIA kit. Interassay precision averaged 8.1% for samples in the range 50-400 micrograms/L; intra-assay precision averaged 3.6% at 230 micrograms/L and 8.7% at 53 micrograms/L. Correlation between the two methods was RIA = 1.13 HPLC + 14.8 (n = 128, r = 0.957, P less than 0.001). Both methods are technically simple to perform.

scholarly journals High-Performance Liquid Chromatographic Method for the Determination of Moniliformin in Corn

1998 ◽  
Vol 81 (5) ◽  
pp. 999-1004 ◽  
Author(s):  
Célestin Munimbazi ◽  
Lloyd B Bullerman
Keyword(s):  
High Performance ◽  
Chromatographic Method ◽  
Solid Phase ◽  
High Performance Liquid Chromatographic ◽  
Reversed Phase ◽  
Detector Response ◽  
Dihydrogen Phosphate ◽  
Sodium Dihydrogen Phosphate ◽  
Liquid Chromatographic Method ◽  
Liquid Chromatographic

Abstract A high-performance liquid chromatographic method using UV absorption was developed for determining moniliformin in corn. The toxin was extracted with water containing 1 % tetrabutylammonium hydrogen sulfate (w/v). Paired moniliformin was partitioned into dichloromethane, which was evaporated to dryness at 50 C. The residue was dissolved in water and applied to a disposable stronganion exchange solid-phase extraction tube. Adsorbed moniliformin was eluted from the tube with 0.05M sodium dihydrogen phosphate monohydrate (pH 5). It was determined by ion-pair reversed-phase chromatography and UV measurement at 229 nm. The minimum detectable amount of pure moniliformin was 0.25 ng/injection (signal-to-noise ratio = 3:1). The detector response was linear from 0.25 to at least 20 ng. The limit of determination was 0.025 μg/g corn. Recoveries of moniliformin from corn spiked at 0.025,0.05,0.25, and 1.0 μg/g averaged 96.5,96.2, 97.2, and 97.8% respectively

Homocysteine and other thiols determined in plasma by HPLC and thiol-specific postcolumn derivatization

1993 ◽  
Vol 39 (8) ◽  
pp. 1590-1597 ◽  
Author(s):  
A Andersson ◽  
A Isaksson ◽  
L Brattström ◽  
B Hultberg
Keyword(s):  
High Performance ◽  
Colorimetric Detection ◽  
High Performance Liquid Chromatographic ◽  
Reversed Phase ◽  
Disulfide Reduction ◽  
Liquid Chromatographic Method ◽  
Total Homocysteine ◽  
Assay Precision ◽  
Liquid Chromatographic ◽  
Postcolumn Derivatization

Abstract We describe a versatile high-performance liquid-chromatographic method for determining homocysteine and other plasma sulfhydryls. Using three different procedures for preparation of plasma, we determined total, free (non-protein-bound), and reduced forms of homocysteine, cysteine, glutathione, cysteinylglycine, and gamma-glutamylcysteine in human plasma. Sample preparation involves disulfide reduction with dithiothreitol and protein precipitation with sulfosalicylic acid. The assay utilizes isocratic reversed-phase ion-pair liquid chromatography at pH 2.4, postcolumn derivatization with 4,4'-dithiodipyridine, and colorimetric detection at 324 nm. The intra-assay precision (CV) of the method for total homocysteine is 1.5%; the interassay precision over 2.5 months is 2.5%. The detection limit for homocysteine is < 50 nmol/L plasma.

Quantitative Analysis of 5-Hydroxymethylfurfural in Linezolid Injection by High Performance Liquid Chromatography

2020 ◽  
Vol 16 (8) ◽  
pp. 1059-1067
Author(s):  
Jéssica Maurício Batista ◽  
Christian Fernandes
Keyword(s):  
High Performance ◽  
Potassium Phosphate ◽  
Gradient Elution ◽  
High Performance Liquid Chromatographic ◽  
Official Method ◽  
Ph Variation ◽  
Drug Products ◽  
Liquid Chromatographic Method ◽  
Liquid Chromatographic

Background: Linezolid is a synthetic broad-spectrum antibacterial belonging to the class of oxazolidinones. Linezolid for intravenous infusion is isotonized with dextrose. In acidic environment, the dehydration of dextrose produces furan derivatives, 5-hydroxymethylfurfural (5-HMF) being the main one. The determination of this degradation product is of fundamental importance, since there is evidence it is cytotoxic, genotoxic, mutagenic and carcinogenic. However, there is no official method for the determination of 5-HMF in drug products. Objective: The aim of this study was to develop and validate a high performance liquid chromatographic method to quantify 5-HMF in injection of linezolid. Methods: The chromatographic separation, after optimization, was performed on C18 (150 x 4.6 mm, 5 μm) column. Mobile phase was composed of 14 mM potassium phosphate buffer pH 3.0 ([H+] = 1.0 x 10-3) and methanol in gradient elution at 1.0 mL min-1. The injection volume was 10 μL and detection was performed at 285 nm. Results: The method was optimized and validated, showing selectivity, linearity in the range from 0.075 to 9.0 μg mL-1, precision (RSD ≤ 2.0%), accuracy (mean recovery of 100.07%) and robustness for temperature and pH variation. Conclusion: The method was shown to be adequate to determine 5-HMF in injection containing linezolid in routine analysis.

DEVELOPMENT OF VALIDATED RP-HPLC METHOD FOR THE QUANTITATIVE ANALYSIS OF CHROMIUM PICOLINATE III IN A DIET VINEGAR FORMULATION

INDIAN DRUGS ◽  
2013 ◽  
Vol 50 (05) ◽  
pp. 48-52
Author(s):  
A Lodhi ◽  
◽  
A Jain ◽  
B. Biswal
Keyword(s):  
High Performance ◽  
Limit Of Detection ◽  
High Performance Liquid Chromatographic ◽  
Reversed Phase ◽  
Hplc Method ◽  
Chromium Picolinate ◽  
Limit Of Quantification ◽  
Pharmaceutical Dosage Forms ◽  
Liquid Chromatographic Method ◽  
Liquid Chromatographic

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 ODS, 5µm (250×4.6) mm column. The mobile phase consisted of acetonitrile: buffer (60:40 V/V) at a flow rate of 0.5 mL/min. The PDA-detector was set at 264 nm. The developed method showed a good linear relationship in the concentration range from 1.5 – 12.5 µg/mL with a correlation coefficient from 0.999. The limit of detection and limit of quantification were 0.0540513 and 0.1637919 µg/mL respectively.

Sign in / Sign up

Export Citation Format

Share Document