Enzyme Immunoassay for Screening Sulfamethazine Residues in Swine Blood

Abstract An enzyme immunoassay (EIA) was developed to screen for residues of sulfamethazine (SMT) and its metabolites in swine blood. Swine blood vas treated with perchloric acid and centrifuged. The supernatant solution was neutralized with K2HP04, centrifuged, and applied to a reverse phase Cg cartridge. The analytes were eluted with methanol- water (2 + 3), and the eluate was diluted and assayed. Average recoveries, using 14C-labeled compounds, were 73, 72, 61, and 62% for SMT, W4-glucosyISMT, iV4-acetylSMT, and W4-desaminoSMT, respectively. Tubes coated with antibody were incubated with the eluate and an SMT-P-galactosidase conjugate. Bound enzyme was detected with fluorogenic substrate. When blood was fortified with 0.1 ppm SMT or a molar equivalent of metabolite, the average relative response of the EIA was 100%, control blood; 61%, SMT; 66%, glucosylSMT; 60%, acetylSMT; and 77% desaminoSMT.

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Evaluation of a Commercial Enzyme Immunoassay Kit for Serum Carcinoembryonic Antigen

Annals of Clinical Biochemistry International Journal of Laboratory Medicine ◽

10.1177/000456328101800412 ◽

1981 ◽

Vol 18 (4) ◽

pp. 248-251 ◽

Cited By ~ 1

Author(s):

Dickran Fabricatorian ◽

Neil D Gallagher

Keyword(s):

Horseradish Peroxidase ◽

Guinea Pig ◽

Carcinoembryonic Antigen ◽

Enzyme Immunoassay ◽

Perchloric Acid ◽

Acid Extraction ◽

Commercial Enzyme ◽

Serum Carcinoembryonic Antigen ◽

Commercial Enzyme Immunoassay

An enzyme immunoassay kit for carcinoembryonic antigen (CEA) that uses plastic beads coated with guinea-pig anti-CEA as first antibody and goat anti-CEA conjugated with horseradish peroxidase as second antibody has been evaluated. The method does not involve perchloric acid extraction and therefore avoids a dialysis procedure. It is accurate, sensitive, and inexpensive to operate, and provides values comparable to those obtained with the Roche-CEA Z-Gel radioimmunoassay.

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Urinary excretion of arterial blood prostaglandins and thromboxanes in man

AJP Endocrinology and Metabolism ◽

10.1152/ajpendo.1982.242.3.e171 ◽

1982 ◽

Vol 242 (3) ◽

pp. E171-E177 ◽

Cited By ~ 1

Author(s):

R. D. Zipser ◽

K. Martin

Keyword(s):

Renal Artery ◽

Blood Concentration ◽

Isotope Ratio ◽

Fractional Excretion ◽

Labeled Compounds ◽

Prostaglandin I2 ◽

Reverse Phase ◽

Dual Isotope ◽

Arterial Blood ◽

Brachial Vein

To determine the fraction of the arterial prostaglandin E2 (PGE2), 6-ketoprostaglandin F1 alpha (6-keto-PGF1 alpha), and thromboxane B2 (TXB2) that is excreted unmetabolized into human urine, the 3H-labeled compounds were separately infused into the renal artery or brachial vein of 23 subjects. Urine extracts were subjected to sequential chromatography on thin-layer plates, Sephadex LH-20, and reverse-phase high-pressure liquid chromatography to isolate the unmetabolized fraction. Dual isotope ratio techniques were used to identify peak fractions, to assess purity, and to calculate recovery. Following renal artery infusions, 32.2% of 6-keto-PGF1 alpha, 13.5% of TXB2, and 3.9% of PGE2 were excreted unmetabolized. Calculated fractional excretion of these compounds on a single transit through the kidney are approximately 30, 13, and 3.9%, respectively. Following brachial vein infusion of [3H]prostaglandin I2, 2.7% of the infusate was excreted as 6-keto-PGF1 alpha, suggesting that circulating prostaglandin I2 may contribute to urinary 6-keto-PGF1 alpha. When combined with published measurements of urinary PGE2, 6-keto-PGF1 alpha, and TXB2, these data can be used to calculate the maximum arterial blood concentration of these substances. The results indicate that arterial blood concentration of PGE2, TXB2, and 6-keto-PGF1 alpha in man are only a few picograms per milliliter or less.

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Enzyme Linked Immunosorbent Assay (ELISA)

Natural Sciences Engineering and Technology Journal ◽

10.37275/nasetjournal.v1i2.6 ◽

2021 ◽

Vol 1 (2) ◽

pp. 29-38

Author(s):

Maya Chandra Dita

Keyword(s):

Quality Control ◽

Enzyme Immunoassay ◽

Immunosorbent Assay ◽

Solid Phase ◽

Control Measures ◽

Diagnostic Tools ◽

Enzyme Linked Immunosorbent Assay ◽

Antigen Binding ◽

Fluorogenic Substrate ◽

Specific Antibodies

Enzyme immunoassay (EIA) and enzyme-linked immunosorbent assay (ELISA) are both widely used as diagnostic tools in medicine and as quality control measures in many industries. ELISA has been the system of choice when testing soluble antigens and antibodies. EIA / ELISA uses the basic immunological concept of antigen binding to specific antibodies, which allows the detection of small amounts of antigens such as proteins, peptides, hormones or antibodies in fluid samples. In all protocols, solid-phase reagents are incubated with secondary or tertiary reactants covalently coupled with the enzyme. The unbound conjugate is washed and a chromogenic or fluorogenic substrate is added.

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Determination of Valdecoxib in Human Plasma Using Reverse Phase HPLC

E-Journal of Chemistry ◽

10.1155/2011/148938 ◽

2011 ◽

Vol 8 (2) ◽

pp. 875-881

Author(s):

Prafulla Kumar Sahu ◽

K. Ravi Sankar ◽

M. Mathrusri Annapurna

Keyword(s):

Human Plasma ◽

Perchloric Acid ◽

Mobile Phase ◽

Internal Standard ◽

Clinical Settings ◽

Reverse Phase Hplc ◽

Reverse Phase ◽

Extraction Recovery ◽

Rp Hplc

An RP-HPLC analytical method for estimation of valdecoxib in human plasma was developed and validated. Protein precipitation and valdecoxib extraction from plasma (200 μL) was carried out by adding 800 μL perchloric acid (5%, v/v in water) containing nimesulide as the internal standard followed by vortex mixing and centrifugation. The supernatant (20 μL) was then injected onto an ODS C18(25 cm×4.6 mm) column from Shimadzu. The mobile phase comprised of acetonitrile and water (35: 65) with a total run time of 12 min and the wavelength of the detector was set at 244 nm. The extraction recovery of valdecoxib from plasma was >95% and the calibration curve was linear (r2= 0.999) over valdecoxib concentrations ranging from 20 to 1400 μg/mL (n= 10). The method had an accuracy of >92% and LOD and LLOQ of 3.58 μg/mL and 13.45 μg/mL respectively. The method reported is simple, reliable, precise, accurate and has the capability of being used for determination of Valdecoxib in clinical settings.

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Extended Preservation of Iron for Transmission

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100061781 ◽

1967 ◽

Vol 25 ◽

pp. 354-355

Author(s):

E. P. Abrahamson II ◽

M. W. Dumais

Keyword(s):

Acid Solution ◽

Perchloric Acid ◽

Microscopy Study ◽

Perchloric Acid Solution ◽

Transmission Microscopy ◽

Iron Base ◽

Cold Stage

In a transmission microscopy study of iron and dilute iron base alloys, it was determined that it is possible to preserve specimens for extended periods of time. Our specimens were prepunched from 5 to 8 mil sheet to microscope size and annealed for several hours at 700°C. They were then thinned in a glacial acetic-12 percent perchloric acid solution using 10 volts and 20 milliamperes, at a temperature of 8 to 14°C.It was noted that by the use of a cold stage, the same specimen can be observed for periods up to one week without excess contamination. When removal of the specimen from the column becomes necessary, it was observed that a specimen may be kept for later observation in 1,2 dichloroethene or methanol for periods in excess of two weeks.

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