Abstract：
:A simple and convenient method using commercially available derivatization reagents is described for the measurement of betaine and N,N-dimethylglycine (DMG) in blood and urine. Precolumn derivatization of plasma or urine is performed directly in acetonitrile without extraction with p-bromophenacyl bromide and crown ether as catalyst. The p-bromophenacyl ester derivatives are then separated by high-performance liquid chromatography, using an isocratic system of acetonitrile and water containing choline. Effluent was monitored at 254 nm. The limit of detection was 5 micromol/L for betaine and 2 micromol/L for DMG. Analytical recovery was >97% for both analytes. Total and within-day CVs were 2.0-4.4% and 0.9-2.2% for DMG. For betaine, the total and within-day CVs were 1.3-5.3% and 0.4-3.8%, respectively. The method is precise and cost-effective and has been used successfully to determine the concentrations of DMG and betaine in human plasma and urine.
journal_name
Clin Chemjournal_title
Clinical chemistryauthors
Laryea MD,Steinhagen F,Pawliczek S,Wendel Usubject
Has Abstractpub_date
1998-09-01 00:00:00pages
1937-41issue
9eissn
0009-9147issn
1530-8561journal_volume
44pub_type
杂志文章abstract：BACKGROUND:Specific gravity (SG) may perform as well as creatinine (CR) correction for adjusting urinary hormone concentrations, as well as offer some advantages. We compared the two methods and applied them to US and Bangladeshi specimens to evaluate their use in different populations. METHODS:Pearson correlations be...
journal_title：Clinical chemistry
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doi：10.1373/clinchem.2004.032292
更新日期：2004-05-01 00:00:00
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journal_title：Clinical chemistry
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更新日期：1990-05-01 00:00:00
abstract：:We describe a competitive enzyme immunoassay, the ExtrAvidin-biotin system, for determining osteocalcin in human serum or plasma. Antibodies were raised against bovine osteocalcin. Binding of the antibodies to osteocalcin was calcium-dependent. Limit of detection is 0.07 nmol/L (0.4 microgram/L). The standard curve fo...
journal_title：Clinical chemistry
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更新日期：1992-10-01 00:00:00
abstract：:We describe a direct radioimmunoassay for serotonin (5-hydroxytryptamine) in cerebrospinal fluid, platelet-poor plasma, and serum. We raised antisera in rabbits against serotonin diazotized to a conjugate of bovine albumin and D,L-p-aminophenylalanine. Polyethylene glycol, alone or in combination with anti-rabbit immu...
journal_title：Clinical chemistry
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更新日期：1982-04-01 00:00:00
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journal_title：Clinical chemistry
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更新日期：1988-08-01 00:00:00
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journal_title：Clinical chemistry
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更新日期：1986-01-01 00:00:00
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journal_title：Clinical chemistry
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更新日期：1995-02-01 00:00:00
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journal_title：Clinical chemistry
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doi：
更新日期：2002-10-01 00:00:00
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journal_title：Clinical chemistry
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doi：
更新日期：2000-01-01 00:00:00
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journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1976-01-01 00:00:00
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journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1977-09-01 00:00:00
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journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1995-04-01 00:00:00
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journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1984-11-01 00:00:00
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journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1990-01-01 00:00:00
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journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1987-12-01 00:00:00
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journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1987-10-01 00:00:00
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journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1991-05-01 00:00:00
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journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1986-06-01 00:00:00
abstract：:We describe a fully automated method of analysis for plasma epinephrine and norepinephrine by use of a two-column system of "high-performance" liquid chromatography. Catecholamines in deproteinized plasma are purified on the first (preparation) column, then transferred automatically to the second (analytical) column i...
journal_title：Clinical chemistry
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doi：
更新日期：1981-12-01 00:00:00
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journal_title：Clinical chemistry
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doi：
更新日期：1987-07-01 00:00:00
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journal_title：Clinical chemistry
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doi：
更新日期：1983-07-01 00:00:00
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doi：
更新日期：1999-08-01 00:00:00
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更新日期：2003-07-01 00:00:00
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更新日期：2004-09-01 00:00:00
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更新日期：2004-07-01 00:00:00
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journal_title：Clinical chemistry
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doi：
更新日期：1996-01-01 00:00:00
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journal_title：Clinical chemistry
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doi：
更新日期：1975-12-01 00:00:00
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journal_title：Clinical chemistry
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doi：
更新日期：1989-06-01 00:00:00
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journal_title：Clinical chemistry
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doi：
更新日期：1985-07-01 00:00:00
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journal_title：Clinical chemistry
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更新日期：1976-01-01 00:00:00
