scholarly journals GC-MS profiling of urinary organic acids evaluated as a quantitative method

1996 ◽  
Vol 42 (10) ◽  
pp. 1609-1615 ◽  
Author(s):  
P Duez ◽  
A Kumps ◽  
Y Mardens
Keyword(s):  
Organic Acids ◽  
Classical Method ◽  
Internal Standard ◽  
Selected Ion Monitoring ◽  
Practical Procedure ◽  
Urinary Organic Acids ◽  
Relative Standard ◽  
Analytical Response ◽  
Quantitative Results ◽  
Curvilinear Relationships

Abstract We assessed the quantitative performances of a classical method for profiling urinary organic acids: ethyl acetate extraction/oxime-trimethylsilyl derivatization/GC-MS. Twenty-seven acids were quantified on the basis of specific ions in both scan and selected-ion monitoring modes. We found that the tuning of the mass detector severely affects the calibration factors, being critical to achieve quantitative results, and we propose a practical procedure for reproducible tuning. Of seven compounds tested, tropic acid was retained as the internal standard suitable for most of the acids of clinical interest; a second internal standard, 2-ketocaproic acid, was used in quantifying keto-acids. The within-day and total relative standard deviations (CVs), estimated from scan-mode analyses of urine, ranged from 2.6% to 12.7% and from 4.2% to 11.8%, respectively. Curvilinear relationships between analytical response and concentration were observed for most of the acids investigated.

Gas Chromatographic-Mass Spectrometric Determination of Epoxidized Soybean Oil Contamination of Foods by Migration from Plastic Packaging

1988 ◽  
Vol 71 (6) ◽  
pp. 1183-1186 ◽  
Author(s):  
Laurence Castle ◽  
Matthew Sharman ◽  
John Gilbert
Keyword(s):  
Fatty Acid ◽  
Soybean Oil ◽  
Lipid Extraction ◽  
Internal Standard ◽  
Epoxidized Soybean Oil ◽  
Gas Chromatography Mass Spectrometry ◽  
Selected Ion Monitoring ◽  
Pvc Film ◽  
Relative Standard

Abstract A method for the quantitative determination of epoxidized soybean oil (ESBO) in foods is described. The procedure involves addition of a diepoxidized fatty acid ester internal standard, followed by lipid extraction from the food and transmethylation under basic conditions. Without further cleanup, the methylated fatty acid epoxides are derivatized to form 1,3-dioxolanes, which are then determined by capillary gas chromatography-mass spectrometry with selected ion monitoring. A detection limit of 2.0 mg/kg of epoxidized soybean oil in foods and a relative standard deviation of 7% have been achieved routinely. The method has been applied successfully to the analysis of cheeses, sandwiches, cakes, and microwave-cooked meals which have been contaminated with ESBO by migration from PVC film.

scholarly journals Development and validation of a GC–MS method for the simultaneous determination of acetochlor, fluorochloridone, and pendimethalin in a herbicide emulsifiable concentrate formulation

2020 ◽  
Vol 32 (4) ◽  
pp. 238-241 ◽  
Author(s):  
Dandan Wang ◽  
Shengde Wu
Keyword(s):  
Internal Standard ◽  
Ternary Mixtures ◽  
Gas Chromatography Mass Spectrometry ◽  
Selected Ion Monitoring ◽  
Limit Of Quantification ◽  
Emulsifiable Concentrate ◽  
Relative Standard ◽  
Replicate Measurements ◽  
Development And Validation

This paper describes a rapid method to simultaneously determine acetochlor, fluorochloridone and pendimethalin present in a herbicide emulsifiable concentrate (EC) formulation using gas chromatography–mass spectrometry (GC–MS). Selected ion monitoring mode was performed to increase the sensitivity, with dibutyl phthalate as an internal standard. The method was validated with respect to linearity, accuracy, precision, and stability. Chromatographic separation was carried out on a TG-5 MS column (30 m × 0.25 mm × 0.25 μm) with helium as the carrier gas at a flow rate of 1.0 mL/min. Calibration curves were linear over 2.0–20.0 μg/mL for each analyte, and the limit of quantification was below 20 ng/mL. Good performance in terms of recovery ranging from 94.5% to 102.5% at 3 concentration levels proved excellent accuracy. The intra- and inter-day relative standard deviations for 6 replicate measurements were always less than 5%. The developed method is simple and efficient for the routine determination of the ternary mixtures in a compound herbicide EC formulation product.

Development and validation of a gas chromatography/mass spectrometry method for the determination of α- and ß-2, 7, 11-cembratriene-4, 6-diols in tobacco

2016 ◽  
Vol 13 (4) ◽  
pp. 341-347
Author(s):  
Wei Gao ◽  
Naiying Wu ◽  
Wenliang Sun
Keyword(s):  
Mass Spectrometry ◽  
Gas Chromatography ◽  
Internal Standard ◽  
Gas Chromatography Mass Spectrometry ◽  
Selected Ion Monitoring ◽  
Content Type ◽  
Chromatography Mass Spectrometry ◽  
Relative Standard ◽  
Development And Validation

Purpose This paper aims to present a robust method for the determination of α- and ß-2, 7, 11-cembratriene-4, 6-diols (α, ß-CBT-diol) in tobacco samples which was developed and validated by using the self-made α, ß-CBT-diol with higher purity as the standard. Design/methodology/approach After the ultrasonic extraction and clean-up procedures, samples were analyzed by gas chromatography/mass spectrometry in selected ion monitoring mode and full scan mode at the same time. A 1-heptadecanol was used as an internal standard. The important parameters, such as extraction conditions and derivation conditions, were optimized. Findings Under the optimal conditions, good results in terms of linearity (R2 > 0.999) and recoveries (93.2-107 per cent) were achieved. The limits of detection were 0.120 and 0.180 μg/ml for α- and ß-CBT-diol, respectively. α, ß-CBT-diol level of analyzed tobacco was found in the range of 34.2-1.26 × 103 μg/g with relative standard deviations below 6 per cent. Originality/value Such a strategy opens a new door towards the development of a simple, robust and sensitive method for the determination of α, ß-CBT-diol in real samples.

ICH/FDA Guidelines-Compliant Validated Stability-Indicating HPLC-UV Method for the Determination of Axitinib in Bulk and Dosage Forms

2020 ◽  
Vol 16 (8) ◽  
pp. 1106-1112
Author(s):  
Ibrahim A. Darwish ◽  
Nasr Y. Khalil ◽  
Mohammad AlZeer
Keyword(s):  
High Performance ◽  
Kinase Inhibitor ◽  
Degradation Products ◽  
Internal Standard ◽  
Dosage Forms ◽  
Uv Detector ◽  
Stability Indicating ◽  
Therapeutic Benefits ◽  
Relative Standard

Background: Axitinib (AXT) is a member of the new generation of the kinase inhibitor indicated for the treatment of advanced renal cell carcinoma. Its therapeutic benefits depend on assuring the good-quality of its dosage forms in terms of content and stability of the pharmaceutically active ingredient. Objective: This study was devoted to the development of a simple, sensitive and accurate stabilityindicating high-performance liquid chromatographic method with ultraviolet detection (HPLC-UV) for the determination of AXT in its bulk and dosage forms. Methods: Waters HPLC system was used. The chromatographic separation of AXT, internal standard (olaparib), and degradation products were performed on the Nucleosil CN column (250 × 4.6 mm, 5 μm). The mobile phase consisted of water:acetonitrile:methanol (40:40:20, v/v/v) with a flow rate of 1 ml/min, and the UV detector was set at 225 nm. AXT was subjected to different accelerated stress conditions and the degradation products, when any, were completely resolved from the intact AXT. Results: The method was linear (r = 0.9998) in the concentration range of 5-50 μg/ml. The limits of detection and quantitation were 0.85 and 2.57 μg/ml, respectively. The accuracy of the method, measured as recovery, was in the range of 98.0-103.6% with relative standard deviations in the range of 0.06-3.43%. The results of stability testing revealed that AXT was mostly stable in neutral and oxidative conditions; however, it was unstable in alkaline and acidic conditions. The kinetics of degradation were studied, and the kinetic rate constants were determined. The proposed method was successfully applied for the determination of AXT in bulk drug and dosage forms. Conclusions: A stability-indicating HPLC-UV method was developed and validated for assessing AXT stability in its bulk and dosage forms. The method met the regulatory requirements of the International Conference on Harmonization (ICH) and the Food and Drug Administration (FDA). The results demonstrated that the method would have great value when applied in quality control and stability studies for AXT.

Development and Validation of a New Method for the Determination of Anti-hepatitis C Agent Simeprevir in Human Plasma using HPLC with Fluorescence Detection

2020 ◽  
Vol 16 (4) ◽  
pp. 428-435
Author(s):  
Ahmed F.A. Youssef ◽  
Yousry M. Issa ◽  
Kareem M. Nabil
Keyword(s):  
Hepatitis C ◽  
Human Plasma ◽  
Fluorescence Detection ◽  
Internal Standard ◽  
Protein Precipitation ◽  
Assay Method ◽  
Fluorescence Detector ◽  
Limit Of Quantification ◽  
Relative Standard

Background: Simeprevir is one of the recently discovered drugs for treating hepatitis C which is one of the major diseases across the globe. Objective: The present study involves the development of a new and unique High-Performance Liquid Chromatography (HPLC) method using fluorescence detection for the determination of simeprevir (SIM) in human plasma. Methods: Two methods of extractions were tested, protein precipitation using acetonitrile and liquidliquid extraction. A 25 mM dipotassium hydrogen orthophosphate (pH 7.0)/ACN (50/50; v/v), was used as mobile phase and C18 reversed phase column as the stationary phase. The chromatographic conditions were optimized and the concentration of simeprevir was determined by using the fluorescence detector. Cyclobenzaprine was used as an internal standard. Results: Recovery of the assay method based on protein precipitation was up to 100%. Intra-day and inter-day accuracies range from 92.30 to 107.80%, with Relative Standard Deviation (RSD) range 1.65-8.02%. The present method was successfully applied to a pharmacokinetic study where SIM was administered as a single dose of 150 mg SIM/capsule (Olysio®) to healthy individuals. Conclusion: This method exhibits high sensitivity with a low limit of quantification 10 ng mL-1, good selectivity using fluorescence detection, wide linear application range 10-3000 ng mL-1, good recovery and highly precise and validation results. The developed method can be applied in routine analysis for real samples.

scholarly journals Quantitative Determination of Azithromycin in Human Plasma by Liquid Chromatography–Mass Spectrometry and its Application in Pharmackokinetic Study

2012 ◽  
Vol 11 (1) ◽  
pp. 55-63 ◽  
Author(s):  
Maizbha Uddin Ahmed ◽  
Mohammad Safiqul Islam ◽  
Tasmin Ara Sultana ◽  
AGM Mostofa ◽  
Muhammad Shahdaat Bin Sayeed ◽  
...  
Keyword(s):  
Mobile Phase ◽  
Solid Phase ◽  
Internal Standard ◽  
Extraction Process ◽  
Serum Samples ◽  
Limit Of Quantification ◽  
Relative Standard ◽  
Linear Concentration Range ◽  
Linear Concentration

Azithromycin is an effective and well-known antimicrobial agent. In the present study, a simple, sensitive and specific LC/MS/MS method has been developed and validated for the quantification of Azithromycin in  human serum samples using Clarithromycin as internal standard. Azithromycin was extracted from biological matrix  by using solid phase extraction process. The chromatographic separation was performed on Luna C18 (3 ?, 2x150   mm) column with a mobile phase consisting of 35 mM ammonium acetate buffer (mobile phase-A) and acetonitrile  and methanol in ratio of 90:10 ( as mobile phase-B) at a flow rate of 0.25 mL/min. The method was validated over a  linear concentration range of 0.5?50.0 ng/mL and limit of quantification (LOQ) was 0.5 ng/mL with a coefficient of  correlation (r2) = 0.9998. The intra-day and inter-day precision expressed as relative standard deviation were 1.64% – 8.43% and 2.32% – 9.92%, respectively. The average recovery of azithromycin from serum was 98.11%. The method  was successfully applied to a pharmacokinetic study after oral administration of Azithromycin 200 mg/5 ml suspension in healthy Bangladeshi volunteers. DOI: http://dx.doi.org/10.3329/dujps.v11i1.12488 Dhaka Univ. J. Pharm. Sci. 11(1): 55-63, 2012 (June)

scholarly journals An Accurate and Effective Method for Measuring Osimertinib by UPLC-TOF-MS and Its Pharmacokinetic Study in Rats

Molecules ◽  
2018 ◽  
Vol 23 (11) ◽  
pp. 2894 ◽  
Author(s):  
Song-Tao Dong ◽  
Ying Li ◽  
Hao-Tian Yang ◽  
Yin Wu ◽  
Ya-Jing Li ◽  
...  
Keyword(s):  
Matrix Effects ◽  
Internal Standard ◽  
Ultra Performance Liquid Chromatography ◽  
Rat Plasma ◽  
Analysis Method ◽  
T790m Mutation ◽  
Flight Mass Spectrometry ◽  
Relative Standard ◽  
New Generation ◽  
Tof Ms

Osimertinib, a new-generation inhibitor of the epidermal growth factor, has been used for the clinical treatment of advanced T790M mutation-positive tumors. In this research, an original analysis method was established for the quantification of osimertinib by ultra-performance liquid chromatography with time of flight mass spectrometry (UPLC-TOF-MS) in rat plasma. After protein precipitation with acetonitrile and sorafinib (internal standard, IS), they were chromatographed through a Waters XTerra MS C18 column. The mobile phase was acetonitrile and water (including 0.1% ammonia). The relative standard deviation (RSD) of the intra- and inter-day results ranged from 5.38 to 9.76% and from 6.02 to 9.46%, respectively, and the extraction recovery and matrix effects were calculated to range from 84.31 to 96.14% and from 91.46 to 97.18%, respectively. The results illustrated that the analysis method had sufficient specificity, accuracy and precision. Meanwhile, the UPLC-TOF-MS method for osimertinib was successfully applied into the pharmacokinetics of SD rats.

A Comparison of Soxhlet Extraction and Ultrasonic-Assisted Extraction for Analysis of Photoinitiators in Printed Cartonboard Food-Packaging Materials

2012 ◽  
Vol 262 ◽  
pp. 561-566
Author(s):  
Chao Ding ◽  
Fang Wang ◽  
Mei Xia Pang ◽  
Xin Xin Yi ◽  
Feng Tan ◽  
...  
Keyword(s):  
Food Packaging ◽  
Soxhlet Extraction ◽  
Gas Chromatography Mass Spectrometry ◽  
Packaging Materials ◽  
Selected Ion Monitoring ◽  
Food Packaging Materials ◽  
Assisted Extraction ◽  
Relative Standard ◽  
Ultrasonic Assisted ◽  
Phenyl Ketone

A new method was established for detecting a series of photoinitiators (PIs) in printed cartonboard food-packaging materials, which were benzophenone (BP), 4-methylbenzophenone (MBP), 1-hydroxycyclohexyl phenyl ketone (Irgacure184), ethyl-4-dimethylaminobenzoate (EDAB), 2-ethylhexyl-4-dimethylaminobenzoate (EHDAB) and 2-isopropylthioxanthone (ITX) by gas chromatography–mass spectrometry (GC/MS). Extraction was carried out with ethyl acetate by ultrasonic solvent extraction. Samples were analyzed by GC/MS in selected ion monitoring (SIM) mode. The results indicated that six kinds of PIs had good linear relations (R2>0.9989) in the range of 10~200 μg/L. Limit of Detections (LODs) and Limit of Quantifications ( LOQs ) of all kinds of PIs were 0.3~2.6 μg /kg and 1~8 μg/kg, respectively. The recoveries of six kinds of PIs at three kinds of concentrations researched (0.30 μg/kg, 0.60 μg/ kg, 1.0 μg/kg) were ranging from 66.7%~89.4%, with the Relative Standard Deviation (RSD) of 4.2%~10.6% (n=6). The results also suggested that PIs were detected in food packaging materials.

scholarly journals Determination of 1,3-Dichloropropanol in Soy Sauce and Related Products by Headspace Gas Chromatography with Mass Spectrometric Detection: Interlaboratory Study

2005 ◽  
Vol 88 (5) ◽  
pp. 1404-1412 ◽  
Author(s):  
Sarah Hasnip ◽  
Colin Crews ◽  
Nicholas Potter ◽  
Paul Brereton ◽  
Henri Diserens ◽  
...  
Keyword(s):  
Gas Chromatography ◽  
Standard Deviation ◽  
Relative Standard Deviation ◽  
Internal Standard ◽  
Mass Spectrometric ◽  
Soy Sauce ◽  
Headspace Gas Chromatography ◽  
Relative Standard ◽  
Headspace Gas

Abstract An interlaboratory study was performed to evaluate the effectiveness of a headspace gas chromatography (GC) method for the determination of 1,3-dichloro-propan-2-ol (1,3-DCP) in soy sauce and related products at levels above 5 ng/g. The test portion is mixed with an internal standard (d5-1,3-DCP) and ammonium sulfate in a sealed headspace vial. After achieving equilibrium, the headspace is sampled either by gas-tight syringe or solid-phase microextraction (SPME) and analyzed by GC with mass spectrometric detection. 1,3-DCP is detected in the selected-ion mode (monitoring m/z 79 and 81 for 1,3-DCP and m/z 82 for the deuterated internal standard) and quantified by measurement against standards. Test materials comprising soy, dark soy, mushroom soy, and teriyaki sauces, both spiked and naturally contaminated, were sent to 9 laboratories in Europe, Japan, and the United States; of these, 5 used SPME and 4 used syringe headspace analysis. Test portions were spiked at 5.0, 10.0, 20.0, 100.0, and 500.0 ng/g. The average recovery for spiked blank samples was 108% (ranging from 96–130%). Based on results for spiked samples (blind pairs at 5, 10, 20, 100, and 500 ng/g) as well as a naturally contaminated sample (split-level pair at 27 and 29 ng/g), the relative standard deviation for repeatability (RSDr) ranged from 2.9–23.2%. The relative standard deviation for reproducibility (RSDR) ranged from 20.9–35.3%, and HorRat values of between 1.0 and 1.6 were obtained.

Sign in / Sign up

Export Citation Format

Share Document