Analysis of Myo-inositol in Dry Beans by Gas Chromatography of Its Hexaacetate

1972 ◽  
Vol 55 (6) ◽  
pp. 1194-1198
Author(s):  
Richard M Seifert
Keyword(s):  
Mass Spectrometry ◽  
Internal Standard ◽  
Peak Height ◽  
Chromatographic Retention ◽  
Gas Liquid Chromatography ◽  
Standard Curve ◽  
Pinto Bean ◽  
White Bean ◽  
Pinto Beans ◽  
Hydrolysis Of

Abstract A method has been developed for the analysis of myo-inositol in California small white beans, pinto beans, and 2 pinto bean flake products by gas-liquid chromatography of myo-inositol hexaacetate. The identity of myoinositol hexaacetate from bean samples was confirmed by mass spectrometry and chromatographic retention time. A standard curve prepared by plotting peak height vs. μg myoinositol hexaacetate was linear over the range studied, 0.2 to 0.6 μg. Peak heights were measurable in all samples, although inositol hexaacetate was not completely separated in California small white bean samples. An internal standard, perseitol, was used to correct for losses in the procedure. Hydrolysis of phytin was negligible during sample preparation or analysis. Recoveries of 12 to 40 μg inositol from 40 mg samples of California small white beans averaged 113%. These beans contained an average of 71 ppm inositol compared to 215 ppm inositol in similarly prepared pinto beans.

Determination of Volatile Organic Contaminants in Bulk Oils (Edible, Injectable, and Other Internal Medicinal) by Purge-and-Trap Gas Chromatography/Mass Spectrometry

1994 ◽  
Vol 77 (3) ◽  
pp. 647-654 ◽  
Author(s):  
Don W Thompson
Keyword(s):  
Mass Spectrometry ◽  
Gas Chromatography ◽  
Vegetable Oils ◽  
Organic Contaminants ◽  
Internal Standard ◽  
Gas Chromatography Mass Spectrometry ◽  
Purge And Trap ◽  
Standard Curve ◽  
Volatile Organic ◽  
Volatile Organic Contaminants

Abstract Purge-and-trap gas chromatography/mass spectrometry is evaluated for the quantitation of part-per-billion levels of volatile organic contaminants in bulk vegetable oils. Results using 2 purge techniques (direct purging of the heated oil and purging after dispersing the oil on an aluminum oxide powder) and 2 quantitative methods (standard curve and deuterium-labeled internal standard addition) are reported. Twenty volatile compounds and 8 vegetable oils were investigated. Recovery data and estimated detection limits for each compound are reported for each purge technique. Generally acceptable recoveries (70-130% for more than 90% of the analyte spikes) and acceptable detection levels (approximately 4-10 ppb) were obtained for all compounds using either the external standard curve or the deuterium-isotope-labeled internal standard. The use of a dispersant (such as alumina) for sample purging resulted in poor recoveries of the highly volatile contaminants.

Gas-Liquid Chromatographic/Mass Spectrometric Screening Method for T-2 Toxin in Milk

1979 ◽  
Vol 62 (6) ◽  
pp. 1274-1280
Author(s):  
George J Collins ◽  
Joseph D Rosen
Keyword(s):  
Mass Spectrometry ◽  
Electron Impact ◽  
Chemical Ionization ◽  
Impact Ionization ◽  
Trimethylsilyl Ether ◽  
Screening Method ◽  
Internal Standard ◽  
Electron Impact Ionization ◽  
Gas Liquid Chromatography ◽  
Ionization Mass

Abstract A method for the analysis of T-2 toxin in milk is presented. Ethyl acetate extracts of milk samples which had been spiked with T-2 toxin were purified by thin layer chromatography and derivatized with N,O-bis(trimethylsilyl)acetamide to produce the T-2 toxin trimethylsilyl ether (T-2 toxin-TMS). N,O-bis(trimethylsilyl-d9)acetamide was used to make T-2 toxin d9-trimethylsilyl ether (T-2 toxin-d9TMS) which was added to the derivatized milk extract as an internal standard. Samples were analyzed by combined gas-liquid chromatography/mass spectrometry using either electron impact ionization or chemical ionization mass spectrometry. In electron impact ionization analyses, simultaneous monitoring of the T-2 toxin-TMS fragment ion at m/z 436 and the T-2 toxin-d9TMS fragment ion at m/z 445 gave a T-2 toxin-TMS detectability estimated at 6 μg/kg. In chemical ionization analyses, the T-2 toxin-TMS fragment ion at m/z 377 and the T-2 toxin-d9TMS fragment ion at m/z 386 were simultaneously monitored to give a T-2 toxin-TMS detectability estimated at 3 μg/kg. Average recovery was 85% at 200 μg/kg and 65% at 20 μg/kg.

Mannitol estimation in biological fluids by gas-liquid chromatography of trimethylsilyl derivatives.

1980 ◽  
Vol 26 (3) ◽  
pp. 441-443 ◽  
Author(s):  
M F Laker ◽  
J N Mount
Keyword(s):  
Liquid Chromatography ◽  
Biological Fluids ◽  
Internal Standard ◽  
Peak Height ◽  
Gas Liquid Chromatography ◽  
Height Measurement ◽  
Standard Solution ◽  
Trimethylsilyl Derivatives

Abstract We describe a procedure for estimating mannitol concentrations in biological fluids. Samples are mixed with internal standard solution (alpha-methylglucose), deproteinized if necessary, desalted, and dried. Specimens are then derivatized by adding pyridine/bis(trimethylsilyl)acetamide/trimethylchlorosilane and heating at 60 degrees C for 30 min. Samples are chromatographed on a 275-cm column of 10% OV-17, operated at 190 degrees C, and quantitated by peak-height measurement. The technique is linear, accurate, precise, sensitive, and free from interference. It has been used to measure mannitol in plasma, urine, and bile.

Gas-Liquid Chromatographic Determination of Oxydemeton-Methyl in Commercial Formulations

1978 ◽  
Vol 61 (3) ◽  
pp. 500-503
Author(s):  
Leonard R Schronk ◽  
Billy M Colvin ◽  
Alan R Hanks
Keyword(s):  
Rapid Determination ◽  
Internal Standard ◽  
Chromatographic Determination ◽  
Peak Height ◽  
Detector Response ◽  
Gel Chromatography ◽  
Gas Liquid Chromatography ◽  
Flame Ionization ◽  
Silica Gel Chromatography

Abstract Flame ionization gas-liquid chromatography (GLC) with a 10% DC-200 on 80-100 mesh Gas-Chrom Q column is used for the rapid determination of oxydemeton-methyl in commercial formulations. The detector response is linear for 1.0–10.0 μg oxydemeton-methyl, with a sensitivity of 4 ng. The column was stabilized before analysis by injection of a lecithin solution. Samples were diluted with chloroform and injected; peak height ratios were used for quantitation with fluoranthrene as the internal standard. Carbaryl was removed from mixed formulations by silica gel chromatography, oxydemeton- methyl was eluted with methanolchloroform (2+98), and the eluate was collected for infrared (IR) and GLC analyses. Methoxychlor and Karathane were removed by chromatography on Florisil before IR analysis. GLC results compare favorably with those for IR, with recoveries ranging from 98.44 to 102.88% for spiked formulations.

scholarly journals A Rapid and Selective LC-MS/MS Method for Quantification of Quetiapine in Human Plasma and its Application to Pharmacokinetic Study on Indian Schizophrenia Patients

2011 ◽  
Vol 8 (4) ◽  
pp. 1802-1814 ◽  
Author(s):  
S. Ravinder ◽  
A. T. Bapuji ◽  
K. Mukkanti ◽  
M. Nagesh ◽  
H. L. V. Ravikiran
Keyword(s):  
Mass Spectrometry ◽  
Human Plasma ◽  
Pharmacokinetic Study ◽  
Dynamic Range ◽  
Solid Phase ◽  
Multiple Reaction Monitoring ◽  
Internal Standard ◽  
Plasma Samples ◽  
Standard Curve ◽  
Multiple Reaction Monitoring Mode

A rapid, robust and selective high pressure liquid chromatography–positive electrospray ionization tandem mass spectrometry method has been developed and validated for the quantification of quetiapine (QUE) in human plasma with K2EDTA using oxcarbazepine (IS) as an internal standard. Analyte and internal standard were extracted from human plasma by solid-phase extraction using acetonitrile. The eluted samples were chromatographed on a C18 column by using a 10:75:15v/v mixture of ammonium formate buffer (5 mM, pH 4.50) and acetonitrile and methanol as an isocratic mobile phase at a flow rate of 0.4 mL/min and analyzed by mass spectrometry in the multiple reaction monitoring mode using the respective [M+H]+ions,m/z384.3/253.2 for Quetiapine andm/z253.1/208.1 for the internal standard. The assay exhibited a linear dynamic range of 5.01 - 2501.04 ng/mL for quetiapine in human plasma. Acceptable precision and accuracy were obtained for concentrations over the standard curve range. A run time of 2.5 min for each sample made it possible to analyze 300 patient plasma samples per day. The validated method has been successfully used for the estimation of quetiapine in real time schizophrenia patient’s plasma samples for pharmacokinetic study.

scholarly journals The separation and sequencing of permethylated peptides by mass spectrometry directly coupled to gas-liquid chromatography

1976 ◽  
Vol 157 (3) ◽  
pp. 777-780 ◽  
Author(s):  
J D Priddle ◽  
K Rose ◽  
R E Offord
Keyword(s):  
Mass Spectrometry ◽  
Molecular Weight ◽  
Chemical Ionization ◽  
Chromatographic Retention ◽  
Gas Liquid Chromatography ◽  
Retention Data ◽  
Primary Sequence ◽  
Peptide Derivatives ◽  
Derivatives Of

The use of g.l.c. coupled to mass spectrometry to separate and sequence permethylated acetyl- and trifluoroacetyl-peptides in a single operation is described. Both electron impact and chemical ionization were used to induce fragmentation, and the latter was found to be more sensitive. Chromatographic retention data are presented which suggest that peptide derivatives of molecular weight of at least 750 are accessible to the technique. The application of our methods to the determination of the primary sequence of proteins is discussed.

Simultaneous gas-chromatographic analysis for phenobarbital, diphenylhydantoin, carbamazepine, and primidone in serum.

1976 ◽  
Vol 22 (6) ◽  
pp. 769-771 ◽  
Author(s):  
C V Abraham ◽  
H D Joslin
Keyword(s):  
Chromatographic Analysis ◽  
Limit Of Detection ◽  
Internal Standard ◽  
Peak Height ◽  
Gas Liquid Chromatography ◽  
Toxic Concentration ◽  
Sensitive Determination ◽  
Derivatives Of ◽  
Methyl Phenyl

Abstract We describe a simple, sensitive determination of phenobarbital, diphenylhydantoin, carbamazepine, and primidone in serum, by use of gas-liquid chromatography with temperature programming. The methylated derivatives of these anticonvulsants are well resolved, as was 5-(p-methyl-phenyl)-5-phenylhydantoin, the internal standard. The proposed procedure requires only 0.20 ml of serum and can be done in less than 30 min. The lower limit of detection for each of the drugs is 0.5 mg/liter. Analytical recoveries of drug from serum were excellent and peak height and concentration were linearly related up to twice the toxic concentration for serum.

Metabolism of amphetamines by Mycobacterium smegmatis

1980 ◽  
Vol 26 (3) ◽  
pp. 343-349 ◽  
Author(s):  
Ronald T. Coutts ◽  
Brian C. Foster
Keyword(s):  
Mass Spectrometry ◽  
Liquid Chromatography ◽  
Mycobacterium Smegmatis ◽  
Alkyl Substituent ◽  
Acetyl Derivative ◽  
The Other ◽  
Gas Liquid Chromatography ◽  
Considerable Influence ◽  
Hydrolysis Of ◽  
Oxygenated Products

Amphetamine and five N-alkylated homologues were readily metabolized by Mycobacterium smegmatis and the products obtained were identified by gas–liquid chromatography and mass spectrometry. The N-alkyl substituent had a considerable influence on the degree and mechanism of biotransformation. With the exception of the N-isopropyl derivative, all of the N-alkylated homologues were dealkylated to amphetamine which was then conjugated to the N-acetyl derivative. The degree of N-oxygenation of these substrates was significantly different from that observed in mammalian and fungal systems where four products are generally recovered. Mycobacterium smegmatis N-oxygenation of amphetamine did not occur, whereas all N-alkylated amphetamines were converted to the corresponding nitrones or, in the case of methamphetamine, to 1-phenyl-2-propanone oxime. No other N-oxygenated products were isolated. Mycobacterium smegmatis metabolism of 1-phenyl-2-propanone oxime, N-hydroxyamphetamine. N-hydroxy-N-(n-propyl)amphetamine, and the nitrone, α-methyl-N-(n-propylidene) benzeneethanamine N-oxide, was also studied. Some hydrolysis of the oxime to 1-phenyl-2-propanone was observed. The other three substrates were metabolized to amphetamine and N-acetylamphetamine.

Spontaneous hydrolysis of heroin in buffered solution

1978 ◽  
Vol 56 (4) ◽  
pp. 665-667 ◽  
Author(s):  
Paul T. Smith ◽  
M. Hirst ◽  
C. W. Gowdey
Keyword(s):  
Liquid Chromatography ◽  
Rate Constant ◽  
Phosphate Buffer ◽  
Internal Standard ◽  
Order Rate Constant ◽  
Gas Liquid Chromatography ◽  
First Order ◽  
Order Rate ◽  
Spontaneous Hydrolysis ◽  
Hydrolysis Of

Electron-capture gas–liquid chromatography was used to study the spontaneous hydrolysis of heroin in phosphate buffer (pH 6.4 and pH 7.4) at 23 °C. Aliquots of solution were taken over a 24-h period. After extraction at pH 8.9 into propan-2-ol (10%) – ethyl acetate, deacetylated products were made into heptafluorobutyrate derivatives which were analyzed quantitatively using nalorphine as the internal standard. Heroin decomposes to O6-monoacetylmorphine (O6-MAM) under these conditions. Further decomposition to morphine was not observed. Spontaneous hydrolysis was faster at pH 7.4 (first-order rate constant, 9.6 × 10−5 min−1) than at pH 6.4 (first-order rate constant, 3.0 × 10−5 min−1). In 24 h, the decomposition to O6-MAM was 13 and 4%, respectively.

Analysis of Thiamine in Pinto Beans by Gas Chromatography of the Sulfite Cleavage Product 5-(2-Hydroxyethyl)-4-methylthiazole

1973 ◽  
Vol 56 (5) ◽  
pp. 1273-1276
Author(s):  
Richard M Seifert ◽  
Charlotte Fung Miller
Keyword(s):  
Mass Spectrometry ◽  
Gas Chromatography ◽  
Retention Time ◽  
Chromatographic Method ◽  
Cleavage Product ◽  
Pinto Bean ◽  
Pinto Beans ◽  
Gas Chromatographic Method ◽  
Good Agreement

Abstract A gas chromatographic method has been developed for the analysis of thiamine in pinto beans. The method should be applicable to other products. Thiamine is extracted and then quantitatively split by sulfite treatment to give the ether-extractable 5-(2-hydroxyethyl)-4-methylthiazole. The thiazole was analyzed by GLC. Its purity and identity were confirmed by mass spectrometry and GLC retention time. Total thiamine (as the HCl) calculated from the analyzed thiazole averaged 164 ±16 μg/25 g pinto beans. Recovery of total thiamine in 25 g pinto bean samples containing added thiamine HCl (100–500 μg) ranged from 97 to 83%. GLC analysis of pinto bean samples was in good agreement with analysis by the thiochrome method at levels of 5.9–8.6 μg/g, but results were more variable at lower levels.

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