Abstract：
BACKGROUND:Quantitative, miniaturized nucleic acid assays and immunoassays can be developed with single microparticles, microfluorometric detection, and intrinsically fluorescent lanthanide chelates in a multiple assay format to decrease reagent consumption, cost, and assay time. We used recombinant Fab fragments to capture and detect free and total prostate-specific antigen (PSA) from serum in a submicroliter volume single-particle immunoassay. METHODS:Genetically engineered thiol-Fab or thiolated monoclonal antibodies (mAbs) were covalently attached onto uniformly sized 60-microm maleimide-activated microparticles. Free and total PSA were detected with europium- or terbium-labeled Fab fragments on a single microparticle using a microfluorometer in a time-resolved mode. RESULTS:The detection limit of the free- and total-PSA assays (mean + 3 SD of zero calibrator) was 0.35 microg/L, with a total volume of 330 nL per particle. An excellent correlation was found in microparticle and microtiter-well assays for 21 serum samples: slopes for free and total PSA were 1.06+/-0.03 and 1.03+/-0.02, respectively (S(y|x) = 0.084 and 0.057 microg/L), with intercepts of 0.013+/-0.018 and 0.013+/-0.017 microg/L (R>0.99). Furthermore, the particle-immobilized Fab fragment had a PSA binding capacity 1.5-fold higher than the intact mAb capacity on a single microparticle. Capacity, kinetics, and sensitivity of the Fab fragment and intact mAb assays in the microparticle and microtiter well formats are discussed. CONCLUSIONS:With site-specific (cysteine tail) covalent attachment of Fab fragments on a microparticle, subattomole amounts of PSA can be detected quantitatively.
journal_name
Clin Chemjournal_title
Clinical chemistryauthors
Härmä H,Tarkkinen P,Soukka T,Lövgren Tsubject
Has Abstractpub_date
2000-11-01 00:00:00pages
1755-61issue
11eissn
0009-9147issn
1530-8561journal_volume
46pub_type
杂志文章abstract：:A competitive solid-phase fluoroenzymeimmunoassay has been developed for rapidly measuring 5 beta-pregnane-3 alpha, 20 alpha-diol-3 alpha-glucuronide (Pd-3G) directly in diluted specimens of pre-breakfast urine. The assay involves use of an antiserum to Pd-3G and enzyme-labeled antigen prepared by chemically linking g...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1984-02-01 00:00:00
abstract：BACKGROUND:Different technologies, such as quantitative real-time PCR or microarrays, have been developed to measure microRNA (miRNA) expression levels. Quantification of miRNA transcripts implicates data normalization using endogenous and exogenous reference genes for data correction. However, there is no consensus ab...
journal_title：Clinical chemistry
pub_type： 杂志文章,评审
doi：10.1373/clinchem.2015.239459
更新日期：2015-11-01 00:00:00
abstract：:We describe a sensitive beta-endorphin (beta-EP) radioimmunoassay specific for beta-EP 1-31 applied to human ventricular and lumbar cerebrospinal fluid (CSF). Specificity was documented by reversed-phase HPLC of CSF pools. Simultaneous ventricular and lumbar CSF samples from 13 patients suspected of having normal-pres...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1992-06-01 00:00:00
abstract：:We report the results of a laboratory and clinical evaluation of a commercial kit procedure (Immuno Nuclear Corp.) for measuring the mid-region of the parathyrin molecule. The estimated dose at 50% binding averaged 130 pmol/L, and the minimum detectable concentration was 14 pmol/L. The within-assay CV was less than or...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1986-11-01 00:00:00
abstract：:Ammonia concentrations in plasma may increase because of contamination and deterioration of blood components during specimen handling and storage. Using replicate specimens from healthy volunteers, we studied influences of specimen processing and storage procedures on ammonia measurements made with a self-contained re...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1984-06-01 00:00:00
abstract：:A column-switching HPLC system was utilized for the simultaneous determination of epinephrine, norepinephrine, dopamine, serotonin, and their metabolites metanephrine, normetanephrine, 3, 4-dihydroxyphenylacetic acid, homovanillic acid, and 5-hydroxyindoleacetic acid in human urine. The sample was injected directly on...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1999-02-01 00:00:00
abstract：:We describe a chromatographic system involving a high-performance chemically-bonded reverse-phase column and fluorescence detection for measurement of indoles in urine. We controlled retention and selectivity by optimizing the methanol content and pH of the mobile phase. Six reference indoles were separated in less th...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1976-02-01 00:00:00
abstract：:For 51 liver allograft recipients, we evaluated whether serum profiles of delta (Bd) and conjugated bilirubins (Bc) could be used to diagnose rejection during the first 30-50 postoperative days, in comparison with histology as the "gold standard." Daily measurements of aspartate aminotransferase, alkaline phosphatase,...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1990-01-01 00:00:00
abstract：BACKGROUND:The analysis of bodily fluids using SELDI-TOF MS has been reported to identify signatures of spectral peaks that can be used to differentiate patients with a specific disease from normal or control patients. This report is the 2nd of 2 companion articles describing a validation study of a SELDI-TOF MS approa...
journal_title：Clinical chemistry
pub_type： 杂志文章,多中心研究
doi：10.1373/clinchem.2007.091496
更新日期：2008-01-01 00:00:00
abstract：BACKGROUND:Consideration of circulating biomarkers for risk stratification in heart failure (HF) is recommended, but the influence of atrial fibrillation (AF) on prognostic performance of many markers is unclear. We investigated the influence of AF on the prognostic performance of circulating biomarkers in HF. METHODS...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：10.1093/clinchem/hvaa287
更新日期：2021-01-08 00:00:00
abstract：BACKGROUND:Dried blood spots (DBS) are a convenient and inexpensive method for biobanking. Although many countries have established population-based DBS biobanks from neonatal screening programs, the quality and usefulness of DNA from DBS have not been extensively assessed. METHODS:We compared 4 common DNA extraction ...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：10.1373/clinchem.2007.087510
更新日期：2007-08-01 00:00:00
abstract：:We evaluated and compared five commercial radioimmunoassay kits with a standard counter-immunoelectrophoretic assay for the measurement of prostatic acid phosphatase in serum. Four of the five radioimmunoassays performed as described by the supplier with respect to sensitivity, stability, precision, linearity, analyti...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1981-10-01 00:00:00
abstract：BACKGROUND:Direct equilibrium dialysis and direct ultrafiltration free thyroxine (T(4)) assays rely on semipermeable membranes to exclude T(4)-binding serum proteins from dialysates and ultrafiltrates. The presence of these proteins in dialysates or ultrafiltrates will yield spuriously high free T(4) values when free T...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：10.1373/clinchem.2007.085316
更新日期：2007-05-01 00:00:00
abstract：:Ornithine carbamoyltransferase (EC 2.1.3.3) activity is a sensitive, specific indicator of hepatocellular injury. This paper describes development of an improved automated procedure for measurement of this activity. Triethanolamine-ethylenediaminetetraacetate is used as a buffer, and activity is determined by measurin...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1975-05-01 00:00:00
abstract：:We evaluated the analytical performance of Trinder's glucose oxidase (EC 1.1.3.4)/peroxidase (EC 1.11.1.7) 4-aminophenazone-phenol method for the quantification of serum glucose as adapted to the Technicon SMAC. Our results correlated well with those by the routine SMAC glucose oxidase/peroxidase 3-methyl-2-benzothiaz...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1979-10-01 00:00:00
abstract：:Values for insulin-mediated glucose disposal vary continuously throughout a population of apparently healthy individuals, with at least a sixfold variation between the most insulin sensitive and most insulin resistant of these individuals. The more insulin resistant a person, the more insulin must be secreted to preve...
journal_title：Clinical chemistry
pub_type： 杂志文章,评审
doi：10.1373/clinchem.2005.048611
更新日期：2005-06-01 00:00:00
abstract：:Unsaturated cobalamin-binding capacity in plasma (P-UBBC) is determined by use of a silica gel (QUSO G32) to separate haptocorrin (P-ApoHC) and transcobalamin (P-ApoTC). The method is sensitive and precise: detection limit 13 pmol/L, interassay coefficients of variation 3% for P-UBBC (mean = 1080 pmol/L), 4% for P-Apo...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1989-07-01 00:00:00
abstract：:We compared cardiac troponin I (cTnI), using Access, Sanofi Pasteur, and cardiac troponin T (cTnT), using Elecsys, Boehringer Mannheim, in the first two routine blood samplings in a routine panel of cardiac markers for the biochemical diagnostic evaluation of patients with symptoms of acute myocardial infarction (AMI)...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1998-07-01 00:00:00
abstract：BACKGROUND:The prognostic value of changes in paraprotein markers after stem cell transplantation is unknown. We evaluated disease response using serum immunofixation (s-IFIX), total kappa and lambda ratio (KLR), and free light chain (FLC) ratio in myeloma patients who underwent autologous or autologous plus allogeneic...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：10.1373/clinchem.2009.124370
更新日期：2009-08-01 00:00:00
abstract：:I describe a simple, single-tube batch fractionation procedure for separating MM and MB isoenzymes of creatine kinase on a macroporous strong anion exchanger (AG MP-1, Bio-Rad Laboratories). The isoenzymes can be separated in less than 3 min, with a resulting dilution of the serum with no more than an equal volume of ...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1976-01-01 00:00:00
abstract：:Determination of the ratio of testosterone to epitestosterone (T/E) in urine is used to detect testosterone administration in athletes, with a ratio > 6 considered as evidence of an offense. We show that administration of ketoconazole, which inhibits testosterone biosynthesis, may be useful for differentiating between...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1993-09-01 00:00:00
abstract：:We divided patients with brain lesions into three groups: (a) patients with primary or metastatic brain cancer, (b) brain infarctions, and (c) brain contusion(s). We analyzed each patient's sera for creatine kinase isoenzyme BB (CK-BB), using a monoclonal antibody kit (Impres-BB; International Immunoassay Laboratories...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1989-04-01 00:00:00
abstract：:Measured triglyceride concentrations were extremely low (less than 100 mg/L) in the serum of some patients who were receiving hydroxyurea for myeloproliferative diseases. The assay being used to quantify triglycerides was a "cascaded" enzymatic method involving (a) lipase, to generate glycerol from triglycerides; (b) ...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1985-08-01 00:00:00
abstract：:We analyzed pancreatic enzyme data from 508 patients with suspected pancreatitis by neural network analysis, by an Expert multirule generation protocol, and by receiver-operator characteristic (ROC) curve analysis of a single test result. Neural network analysis showed that use of lipase provided the best means for di...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1993-09-01 00:00:00
abstract：:The immunoreactivity of anti-triiodothyronine (anti-T3) IgG, pretreated at acidic pH and adsorbed onto polystyrene beads, was significantly greater than that determined for native anti-T3 IgG immobilized at optimum pH 3.5. Acidic-pH-pretreated IgG, adsorbed at pH 7.0 onto ethanol-treated beads, had less immunoreactivi...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1990-03-01 00:00:00
abstract：BACKGROUND:Immunoassays specific for 1-84 parathyroid hormone (PTH) reportedly reflect the bioactivity of PTH; however, PTH immunoassays can be susceptible to interference by cross-reacting PTH fragments. In addition, these assays currently lack standardization. A methodology using immunocapture purification with liqui...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：10.1373/clinchem.2009.134643
更新日期：2010-02-01 00:00:00
abstract：:The identification of nicotinamide-N1-oxide as a metabolite in the urine of a schizophrenic patient prompted a study of the relative metabolism of nicotinic acid and nicotinamide in mental patients and healthy volunteers. Metabolites quantified included N1-methyl-2-pyridone-5-carboxamide, N1-methyl-4-pyridone-3-carbox...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1976-11-01 00:00:00
abstract：:Concentrations of free thyroxin (T4) and free triiodothyronine (T3) were measured in sera from pregnant women, in subjects with congenitally increased or decreased thyroxin-binding globulin (TBG), and in euthyroid controls. Measured free hormone concentrations were compared with calculated values for free hormone deri...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1983-08-01 00:00:00
abstract：:Recombinant DNA techniques are contributing to the understanding of the pathogeneses of genetic, neoplastic, and viral diseases, and are used in the diagnosis of certain genetic and viral diseases. Such techniques will have wider application in the future and will play an increasing role in the clinical laboratory. Th...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1985-06-01 00:00:00
abstract：BACKGROUND:PCR-based mutation detection is prone to methodological errors, e.g., in restriction length fragment polymorphism (RFLP) and allele-specific amplification (ASA), false PCR results may occur because of technical faults or atypical new mutations. METHODS:We investigated the ability of a genotyping assay based...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1999-12-01 00:00:00
