Gas-Liquid Chromatographic Determination of Polychlorinated Biphenyls and a Selected Number of Chlorinated Hydrocarbons in Serum

1983 ◽  
Vol 66 (1) ◽  
pp. 32-39
Author(s):  
Virlyn W Burse ◽  
Larry L Needham ◽  
Margaret P Korver ◽  
Chester R Lapeza ◽  
John A Liddle ◽  
...  
Keyword(s):  
Polychlorinated Biphenyls ◽  
Chlorinated Hydrocarbons ◽  
Chromatographic Determination ◽  
Gas Liquid Chromatography ◽  
Solvent Fractionation ◽  
Exogenous Compounds ◽  
Activated Silica Gel ◽  
Liquid Chromatographic

Abstract A method is proposed for concurrently determining the levels of multiple intact exogenous compounds in serum, particularly polychlorinated biphenyls (PCBs) as Aroclor (AR) 1254 and chlorinated hydrocarbons (CHs). Bovine serum pools containing in vivo-bound PCBs (as AR 1254) and in vitro-spiked CHs are used to evaluate the method, which encompasses serum denaturation with methanol, mixed solvent extraction, multiple solvent fractionation from activated silica gel, and determination by electron capture gas-liquid chromatography. Mean recoveries of the in vitro-spiked 9 CHs at levels of 2.0-29.1 ppb ranged from 52.8 to 98.4% from trial environmental pools; mean recoveries of the in vivobound PCBs (as AR 1254) were 114.1 and 92.6% at levels of 10 and 50 ppb, respectively.

Gas-Liquid Chromatographic Determination of Organochlorine Pesticides and Polychlorinated Biphenyls in Human Milk

1980 ◽  
Vol 63 (4) ◽  
pp. 736-741 ◽  
Author(s):  
John D Tessari ◽  
Eldon P Savage
Keyword(s):  
Polychlorinated Biphenyls ◽  
Human Milk ◽  
Organochlorine Pesticides ◽  
Milk Fat ◽  
Chromatographic Determination ◽  
Gas Liquid Chromatography ◽  
Quantitative Extraction ◽  
Florisil Column Chromatography ◽  
Liquid Chromatographic Determination ◽  
Liquid Chromatographic

Abstract A method for the detection of organochlorine pesticides and polychlorinated biphenyls (PCBs) in human milk is described. The method involves quantitative extraction of human milk with acetone and hexane. The pesticide and PCB residues are extracted from the milk fat with acetonitrile (ACN) and then partitioned back into hexane by aqueous dilution of the ACN extract. The ACN partitioning is followed by cleanup with Florisil column chromatography, eluting with 6 and 15% mixtures of ethyl ether-hexane. The 6% eluate is concentrated and transferred to a silicic acid column for separation of PCBs from pesticide residues. Compounds are quantitated by gas-liquid chromatography. Recovery studies demonstrated that the procedure provides 68–103% recovery for pesticides and PCBs.

Evaluation of Potential Analytical Approach for Determination of Polychlorinated Biphenyls in Serum: Interlaboratory Study

1983 ◽  
Vol 66 (4) ◽  
pp. 956-968
Author(s):  
Virlyn W Burse ◽  
Larry L Needham ◽  
Chester R Lapeza ◽  
Margaret P Korver ◽  
John A Liddle ◽  
...  
Keyword(s):  
Polychlorinated Biphenyls ◽  
Ethyl Ether ◽  
Analytical Approach ◽  
Chromatographic Determination ◽  
Electron Capture Detection ◽  
Coefficients Of Variation ◽  
The Mean

Abstract Forty-four laboratories participated in evaluation of a method for determining polychlorinated biphenyls (PCBs) as AR 1254 in serum at the parts per billion level. The method involves deproteinating serum with methanol, extracting with hexane-ethyl ether, and eluting PCBs from deactivated silica gel for gasliquid chromatographic determination with electron capture detection. Compounds are quantitated by using the Webb-McCall factors. Five serum pools, 4 containing in vivo-fortified PCBs (as AR 1254) or 8 in vitro-f ortif ied chlorinated hydrocarbons (CHs), or both, were used. For PCB fortification levels of 9.89 (EP 2), 24.74 (EP 3), and 74.20 ppb (EP 4), interlaboratory coefficients of variation (CVs) for collaborators that adhered to protocol were 92.7, 67.6, and 25.8%, respectively. CVs on the same pools analyzed by the Centers for Disease Control (CDC) were 7.4, 7.8, and 4.6%, respectively. Average interlaboratory recoveries for pools EP 2, EP 3, and EP 4 were 138.1,111.2, and 91.1%, respectively, and 99.8,89.6, and 90.4%, respectively, for CDC on the same pools. There was a general decrease in the mean error for those laboratories that had participated in an earlier study in which they were allowed to use their own methods.

scholarly journals Electron Capture Gas-Liquid Chromatographic Study of Metabolites Produced by Some Arthritic Transudate-Associated Organisms In Vitro and In Vivo in Rabbit Models

1978 ◽  
Vol 8 (4) ◽  
pp. 402-409
Author(s):  
John B. Brooks ◽  
A. Richard Melton
Keyword(s):  
Electron Capture ◽  
Fetal Calf Serum ◽  
Calf Serum ◽  
Gas Liquid Chromatography ◽  
Chromatographic Study ◽  
Chamber Model ◽  
Acid Metabolites ◽  
Liquid Chromatographic

Computerized, frequency-pulsed, modulated electron capture gas-liquid chromatography was used to study the acid metabolites produced in vitro in fetal calf serum and in vivo in an animal chamber model. Several strains of Diplostreptococcus agalactiae, Propionibacterium acnes, Staphylococcus aureus , and Streptococcus serogroups A, B, and G were studied. All of these organisms have been reported to be associated with arthritic transudates in humans. Metabolites were detected by this method from derivatized extracts of both spent fetal calf serum and chamber fluids. Since there was little host response to the organisms cultured in the chambers, it is highly probable that the products detected represent metabolites produced in an in vivo type of environment. The metabolic patterns were reproducible and exhibited many similarities in vitro and in vivo. Production of the acids detected was reproducible, and these acids were useful identification markers. The data support published reports (J. B. Brooks, C. C. Alley, and J. A. Liddle, Anal. Chem. 46: 1930-1934, 1974; J. B. Brooks, G. Choudhary, R. B. Craven, D. Edman, C. C. Alley, and J. A. Liddle, J. Clin. Microbiol. 5: 625-628, 1977; J. B. Brooks, R. B. Craven, A. R. Melton, and C. C. Alley, in H. H. Johnson and W. B. Newson, ed., Second International Symposium on Rapid Methods and Automation on Microbiology , 1976; J. B. Brooks, R. B. Craven, D. Schlossberg, C. C. Alley, and F. M. Pitts, J. Clin. Microbiol. 8: 203-208, 1978; J. B. Brooks, D. S. Kellogg, C. C. Alley, H. B. Short, and H. H. Handsfield, J. Infect. Dis. 129: 660-668, 1974) that bacterial metabolites might be detectable in diseased body fluids. The growth characteristics of the organisms in the animal model and fetal calf serum are discussed, and a moderately priced computer for performing data manipulations is evaluated.

scholarly journals THE EFFECTS OF SOME PESTICIDES ON REEF CORALS

1970 ◽  
Vol 17 ◽  
pp. 69-70
Author(s):  
Austin E. Lamberts
Keyword(s):  
Reef Coral ◽  
Chlorinated Hydrocarbons ◽  
In Vitro Studies ◽  
Toxic Substances ◽  
Reef Corals ◽  
Stress Effects ◽  
Skeletal Calcium

While investigating a reef coral kill in Samoa it was speculated that this might have been due to contamination by some chemical. Subsequently, scleractinian reef corals were tested to assess their reactions to 12 commonly used pesticides and toxic substances. The chlorinated-hydrocarbons such as DDT and Endrin produced stress effects in corals subjected to 2ppm for 24 hours in in-vitro studies although the corals continued to deposit skeletal calcium. In-vivo tank experiments suggested that small amounts of these substances in seawater stimulated the corals to deposit skeletal calcium. Other pesticides were much less toxic to the corals.

scholarly journals Mining the Microbiota of the Neonatal Gastrointestinal Tract for Conjugated Linoleic Acid-Producing Bifidobacteria

2004 ◽  
Vol 70 (8) ◽  
pp. 4635-4641 ◽  
Author(s):  
E. Rosberg-Cody ◽  
R. P. Ross ◽  
S. Hussey ◽  
C. A. Ryan ◽  
B. P. Murphy ◽  
...  
Keyword(s):  
Linoleic Acid ◽  
Conjugated Linoleic Acid ◽  
Bifidobacterium Bifidum ◽  
Genomic Diversity ◽  
Gas Liquid Chromatography ◽  
Fecal Material ◽  
Single Strain ◽  
Different Strains

ABSTRACT This study was designed to isolate different strains of the genus Bifidobacterium from the fecal material of neonates and to assess their ability to produce the cis-9, trans-11 conjugated linoleic acid (CLA) isomer from free linoleic acid. Fecal material was collected from 24 neonates aged between 3 days and 2 months in a neonatal unit (Erinville Hospital, Cork, Ireland). A total of 46 isolates from six neonates were confirmed to be Bifidobacterium species based on a combination of the fructose-6-phosphate phosphoketolase assay, RAPD [random(ly) amplified polymorphic DNA] PCR, pulsed-field gel electrophoresis (PFGE), and partial 16S ribosomal DNA sequencing. Interestingly, only 1 of the 11 neonates that had received antibiotic treatment produced bifidobacteria. PFGE after genomic digestion with the restriction enzyme XbaI demonstrated that the bifidobacteria population displayed considerable genomic diversity among the neonates, with each containing between one and five dominant strains, whereas 11 different macro restriction patterns were obtained. In only one case did a single strain appear in two neonates. All genetically distinct strains were then screened for CLA production after 72 h of incubation with 0.5 mg of free linoleic acid ml−1 by using gas-liquid chromatography. The most efficient producers belonged to the species Bifidobacterium breve, of which two different strains converted 29 and 27% of the free linoleic acid to the cis-9, trans-11 isomer per microgram of dry cells, respectively. In addition, a strain of Bifidobacterium bifidum showed a conversion rate of 18%/μg dry cells. The ability of some Bifidobacterium strains to produce CLA could be another human health-promoting property linked to members of the genus, given that this metabolite has demonstrated anticarcinogenic activity in vitro and in vivo.

Gas-Liquid Chromatographic Determination of Sodium Fluoroacetate (Compound 1080)

1980 ◽  
Vol 63 (1) ◽  
pp. 49-55
Author(s):  
Iwao Okuno ◽  
Dennis L Meeker
Keyword(s):  
Liquid Chromatography ◽  
Tissue Sample ◽  
Chromatographic Determination ◽  
Gas Liquid Chromatography ◽  
Tissue Samples ◽  
Fluoroacetic Acid ◽  
Pentafluorobenzyl Bromide ◽  
Liquid Chromatographic Determination ◽  
Liquid Chromatographic

Abstract An analytical method is described for the determination of Compound 1080 (sodium fluoroacetate) residues in 1–10 g tissue. Sample extracts of tissues are cleaned up with silica gel, and Compound 1080 (as fluoroacetic acid) is separated by a micro-distillation procedure. The fluoroacetic acid in the distillate is derivatized with pentafluorobenzyl bromide to form pentafluorobenzyl fluoroacetate which is measured by electron capture gas-liquid chromatography. Recoveries of sodium fluoroacetate from fortified tissue samples averaged about 25%. Despite the limited recoveries, results were quite reproducible, and levels as low at 2 ppm were determined in fortified 1 g samples, and 0.2 ppm in 10 g samples. The method is relatively simple and has been used routinely in our laboratory for the analysis of various types of samples such as grain, and tissues from birds, rodents, and larger animals.

Gas-Liquid Chromatographic Determination of Maleic Hydrazide in Tobacco and Tobacco Smoke

1979 ◽  
Vol 62 (1) ◽  
pp. 171-175 ◽  
Author(s):  
Alfred F Haeberer ◽  
Orestes T Chortyk
Keyword(s):  
Liquid Chromatography ◽  
Tobacco Smoke ◽  
Plant Growth Regulator ◽  
Maleic Hydrazide ◽  
Chromatographic Determination ◽  
Gas Liquid Chromatography ◽  
Trimethylsilyl Derivative ◽  
Liquid Chromatographic Determination ◽  
Liquid Chromatographic

Abstract A method is presented for the determination of the plant growth regulator maleic hydrazide (MH; l,2-dihydro-3,6-pyridazinedione) in tobacco and tobacco smoke. Residues are converted to the bis(trimethylsilyl) derivative before analysis by gas-liquid chromatography. The method has been applied to cigarettes and condensed smoke and has been used to determine the per cent transfer of MH into cigarette smoke. Free MH residues could be determined directly on the tobacco samples, whereas total MH values were obtainable only after acid hydrolysis. In spite of large MH residues in tobacco, only 0.2% of the MH was transferred into smoke.

Rapid Extraction and Gas-Liquid Chromatographic Determination of Benzoic and Sorbic Acids in Beverages

1983 ◽  
Vol 66 (1) ◽  
pp. 209-211
Author(s):  
Ricardo G Coelho ◽  
David L Nelson
Keyword(s):  
Chromatographic Determination ◽  
Gas Liquid Chromatography ◽  
Benzoic Acids ◽  
Ethereal Extract ◽  
Rapid Extraction ◽  
Liquid Chromatographic Determination ◽  
Carbonated Drinks ◽  
Temperature Programmed ◽  
Liquid Chromatographic

Abstract A rapid method for extraction and quantitative determination of sorbic and benzoic acids in carbonated drinks and fruit juices is described. Acidified sample aliquots are transferred onto an Extrelut column. Acid preservatives are then eluted from the column with a mixture of ethyl ether-petroleum ether. Content of preservatives in the concentrated ethereal extract is readily determined by temperature-programmed gas-liquid chromatography without the need to prepare derivatives.

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