Determination of Serum and Urinary Phenylalanine by Gas Chromatography

1973 ◽  
Vol 19 (5) ◽  
pp. 496-498 ◽  
Author(s):  
Z K Shihabi ◽  
G K Summer
Keyword(s):  
Gas Chromatography ◽  
Quantitative Analysis ◽  
Nitrous Acid ◽  
Gas Chromatograph ◽  
Phenyllactic Acid ◽  
Mild Conditions ◽  
Amino Acid Analyzer ◽  
Urine Specimens ◽  
Serum And Urine

Abstract Phenylalanine in serum and urine was determined by gas chromatography after it was converted, by action of nitrous acid, to the corresponding hydroxy acid, phenyllactic acid. After extraction with ether, the phenyllactic acid was derivatized with bis(trimethylsilyl)trifluoroacetamide under mild conditions, and the product was injected directly into the gas chromatograph. The precision of the method was verified by recovery studies and by comparison with the results of quantitative analysis of phenylalanine on an amino acid analyzer. Urine specimens from normal infants and children and from patients with phenylketonuria were analyzed by this method to show that the procedure is applicable to diagnosis of the disorder.

Determination of volatile alcohols and acetone in serum by non-polar capillary gas chromatography after direct sample injection.

1984 ◽  
Vol 30 (10) ◽  
pp. 1672-1674 ◽  
Author(s):  
N B Smith
Keyword(s):  
Gas Chromatography ◽  
Capillary Gas Chromatography ◽  
Capillary Column ◽  
Internal Standard ◽  
Fused Silica ◽  
Gas Chromatograph ◽  
Ionization Detector ◽  
Flame Ionization ◽  
Split Ratio

Abstract In this method for detection and quantification of volatile alcohols by capillary gas chromatography, the serum sample is deproteinized, then directly injected into the gas chromatograph with 1-propanol as the internal standard. The capillary column is a 30-m bonded methylsilicone-coated, fused-silica column. With helium as the carrier gas, the injector inlet is set at a split ratio of 1/30 and the average linear velocity in the column is 25 cm/s. Injector and flame-ionization detector temperatures are 280 degrees C, oven temperature 35 degrees C. Chromatography time is less than 3 min.

Determination of CO2 in Wines by Gas Chromatography

1964 ◽  
Vol 47 (4) ◽  
pp. 730-734
Author(s):  
Howard L Ashmead ◽  
Glenn E Martin ◽  
John A Schmit
Keyword(s):  
Gas Chromatography ◽  
Direct Method ◽  
Alcoholic Beverages ◽  
Gas Chromatograph ◽  
Injection Port ◽  
Carrier Gas ◽  
Solid Adsorbent ◽  
Partial Pressures ◽  
Injection Port Temperature

Abstract A fast and direct method is presented for the determination of CO2 in wines. Partial pressures from other ingredients of alcoholic beverages do not interfere. The method was compared to the manometric procedure under vacuum. An F & M Model 450 Gas Chromatograph with a filament detector was used for C02 determinations. Components were separated by a column 9” long and 1/8” o.d. using charcoal (60—80 mesh) as solid adsorbent. Injection port temperature was ambient; detector and column temperatures were 40°C. Helium was used as a carrier gas at the rate of 50 ml/min. Approximately 50 μ1 samples of standard and unknown solutions were used for the respective determinations.

Determination of five estrogens in wastewater using a comprehensive two-dimensional gas chromatograph

2014 ◽  
Vol 6 (15) ◽  
pp. 5652-5658 ◽  
Author(s):  
Sameera R. Gunatilake ◽  
Taylor L. Clark ◽  
Jose M. Rodriguez ◽  
Todd E. Mlsna
Keyword(s):  
Mass Spectrometry ◽  
Gas Chromatography ◽  
Two Dimensional ◽  
Gas Chromatograph ◽  
Quadrupole Mass ◽  
Trace Level ◽  
Quadrupole Mass Spectrometry ◽  
Novel Method

Comprehensive two-dimensional gas chromatography (GC × GC) hyphenated with rapid quadrupole mass spectrometry was successfully used to develop a novel method for the determination of trace level estrogens in influent and effluent wastewater.

A procedure for the determination of dichloromethane and tetrachloroethene in water using pervaporation and gas chromatography

2011 ◽  
Vol 65 (5) ◽  
Author(s):  
Irena Rutkiewicz ◽  
Wojciech Kujawski ◽  
Jacek Namieśnik
Keyword(s):  
Gas Chromatography ◽  
International Agency ◽  
Gas Chromatograph ◽  
Human Carcinogen ◽  
Enrichment Technique ◽  
Liquid Samples ◽  
Basic Parameters ◽  
Direct Aqueous Injection

AbstractIn the present study, pervaporation was applied to the determination of tetrachloroethene (PCE) and dichloromethane (DCM) in liquid samples. PCE is the most commonly used solvent in drycleaning processes. PCE belongs to group 2A of carcinogens (probably carcinogenic to humans) according to the classification of the International Agency for Research on Cancer (IARC). DCM is also widely used as an industrial solvent for the purification and isolation of intermediates or products. DCM is classified as a “possible” human carcinogen by the IARC. The aim of this study was to evaluate a new procedure for the determination of DCM and PCE in liquid samples based on the pervaporative removal of DCM and PCE from liquid samples as an analyte isolation/enrichment technique, followed by a direct aqueous injection of the extracts onto the column of a gas chromatograph equipped with an electron capture detector (DAI-GC-ECD). The basic parameters of the new PV-DAI-GC-ECD procedure were evaluated.

scholarly journals THE METHOD OF DETERMINATION OF THE SORPTION CAPACITY OF ACTIVATED CARBON BY GAS CHROMATOGRAPHY

2017 ◽  
Vol 1 ◽  
pp. 12-18
Author(s):  
Ksenia Naumenko ◽  
Natalia Frolova ◽  
Oksana Petrusha ◽  
Natalia Chepel
Keyword(s):  
Gas Chromatography ◽  
Activated Carbon ◽  
Sorption Capacity ◽  
Vapor Phase ◽  
Gas Chromatograph ◽  
The Real ◽  
Desorption Branch ◽  
Method Of Determination ◽  
Absorption Characteristics

The article analyzes the possibility of gas chromatography use for determination of sorption capacity of adsorbents on the example of activated carbon BAC-A. The offered method provides the use of gas chromatograph with flame-ionizing detector and with nozzle geyser that is filled with studied adsorbent. At that the isotherms of absorption of substance are constructed by manifestation curve – desorption branch of substance peak on chromatogram. As a result the isotherms of absorption of isoamylol and camphor on activated carbon were constructed and the values of specific sorption capacity for these substances were calculated. This method allows receive fast and precisely the data about absorption characteristics of adsorbent and also adapt the conditions of the study using gas chromatography to the real conditions of adsorption of substances by studied adsorbent (temperature, adsorbent concentration in vapor phase and so on).

scholarly journals Determination of Residues of Eight Synthetic Pyrethroids in Tobacco by Capillary Gas Chromatography

1994 ◽  
Vol 16 (2) ◽  
pp. 65-75
Author(s):  
BS Dattilo ◽  
S Gallo ◽  
G Lionetti
Keyword(s):  
Gas Chromatography ◽  
Film Thickness ◽  
Stationary Phase ◽  
Capillary Gas Chromatography ◽  
Capillary Column ◽  
Limit Of Detection ◽  
Synthetic Pyrethroids ◽  
Gas Chromatograph ◽  
Limit Of Determination

AbstractA method was developed for the simultaneous determination of the residues of the following eight synthetic pyrethroids and their isomers in tobacco: tetramethrin, permethrin, cyfluthrin, cypermethrin, alfamethrin, flucythrinate, fluvalinate and deltamethrin. The pesticides were extracted from ground tobacco by means of acetone:water 9:1 for 5 hours. The extract was diluted with water and partitioned into n-hexane. The organic phase was concentrated to about 1 ml and then purified by a Florisil-SPE column. The gas-chromatographic analyses were run with a gas-chromatograph Carlo Erba Series Mega HRGC 5300 equipped with a capillary column (stationary phase OV-1 - 0.10-0.15 µm film thickness, 25 m long) and a 63Ni electron-capture detector. Two different injection ports were used: split-splitless and cold split-splitless, working both with isothermal and programmed temperatures. Both the limit of detection and the limit of determination were estimated for each compound. Recoveries from fortified samples at level of 1 µgKg-1 are reported.

scholarly journals Study in aroma of sweet natural non Muscat wines 2nd part : quantitative analysis of volatil compounds taking part in aroma of sweet natural wines during ageing

OENO One ◽  
1998 ◽  
Vol 32 (4) ◽  
pp. 211
Author(s):  
Isabelle Cutzach ◽  
Pascal Chatonnet ◽  
R. Henry ◽  
Monique Pons ◽  
Denis Dubourdieu
Keyword(s):  
Mass Spectrometry ◽  
Amino Acids ◽  
Gas Chromatography ◽  
Quantitative Analysis ◽  
Volatile Compounds ◽  
Olfactory Perception ◽  
Maillard Reactions ◽  
Furanic Compounds ◽  
Port Wines

<p style="text-align: justify;">This study is dedicated to quantification, by gas chromatography combined with mass spectrometry, of some volatile compounds founded during ageing of sweet natural wines. Besides determination of the thresholds olfactory perception enable us knowing better the more active compound in sweet natural wines aroma.</p><p style="text-align: justify;">The results enable to know better volatile compounds which are able to produce ageing aromas characteristic of sweet natural wines. These products are always rich in sugar and grown up in a more or less oxidising environment. Logically, many of the compounds identified in this work (derived furanic compounds and many others) are Iinked with chemical like Maillard reactions between sugars and amino-acids. Others compounds as a sotolon need oxidising phenomena to increase in the environment.</p><p style="text-align: justify;">Comparatively, oldest Port wines have been analysed. The compounds measured in these Port wines also exist in French sweet natural wines of type Banyuls and Rivesaltes, keeped under oxidising environment. But the dillerences of concentrations in some compounds discriminate them from the Port wines.</p>

Micromethod for determination of creatinine in biological fluids by high-performance liquid chromatography.

1978 ◽  
Vol 24 (5) ◽  
pp. 747-750 ◽  
Author(s):  
S J Soldin ◽  
J G Hill
Keyword(s):  
High Performance Liquid Chromatography ◽  
Continuous Flow ◽  
Present Method ◽  
High Performance ◽  
Biological Fluids ◽  
Coefficients Of Variation ◽  
Analytical Recovery ◽  
Urine Specimens ◽  
Serum And Urine

Abstract We describe a procedure for the rapid and specific measurement of creatinine, in which it is separated from other compounds in serum or urine by paired-ion chromatography and is quantified by measuring its absorbance at 200 nm. The procedure can be done on as little as 10 microliter of serum. Between-day precision studies for concentrations of 13 and 62 mg/liter yielded coefficients of variation of 6.9 and 2.2%, respectively. Analytical recovery of various amounts of creatinine added to plasma exceeded 95% in all cases. The proposed procedure was compared with the continuous-flow procedure by analyzing a series of serum and urine specimens by both methods. There was excellent agreement for urine specimens, but with serum the results by the present method were significantly (P less than 0.001) lower.

Sign in / Sign up

Export Citation Format

Share Document