University of North Florida
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Stuart Chalk, Ph.D.
Department of Chemistry
University of North Florida
Phone: 1-904-620-1938
Fax: 1-904-620-3535
Website: @unf

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Blood Plasma

Classification: Biological fluid -> blood -> plasma -> chicken

Citations 2

"An Electrochemical Enzyme Immunoassay For Chicken Luteinizing Hormone: Extension Of The Detection Limit By Adequate Control Of The Nonspecific Adsorption"
Anal. Biochem. 1998 Volume 259, Issue 2 Pages 167-175
Ying Qu, Luc R. Berghman and Frans Vandesande

Abstract: A noncompetitive heterogeneous enzyme immunoassay for the determination of chicken luteinizing hormone (LH) was equipped with an electrochemical endpoint in order to further enhance its sensitivity. The immunological principle of the original ELISA remained essentially unchanged, except for the fact that the peroxidase label was replaced by alkaline phosphatase, since in the upgraded version of the assay, p-aminophenyl phosphate was to be used as the substrate of alkaline phosphatase. Enzyme-generated p-aminophenol was injected into a flow injection system and detected amperometrically in a thin-layer flow cell with a glassy carbon electrode at 0.325 V vs Ag/AgCl. A classical problem associated with this type of solid-phase immunoassay is the adsorption of proteins other than the capture antibody to the solid phase. The detection sensitivity is therefore often limited by a large background signal observed in the absence of antigen. In the present study, an experiment was designed to examine in each step of the assay the contribution of each of the potential sources of background current. It was shown that the major contribution to the background current was caused by the nonspecific adsorption of biotinylated secondary antibody. Adsorption of the secondary antibody (biotinylated goat anti-rabbit IgG) to the capture antibody (mouse anti-chicken LHbeta) was clearly a case of specific aspecificity, whereas adsorption to the solid phase itself had to be treated as a nonspecific aspecificity. Addition of 0.25% mouse serum to the secondary antibody as a source of mouse immunoglobulin could overcome the cross-reaction and markedly reduced adsorption to capture antibody. The second part of nonspecific adsorption was eliminated by using combinations of Tween 20 and bovine serum albumin as blocking agents. Controlling the adsorption of the biotinylated secondary antibody in this way decreased the detection limit from 39 pg/ml in the original assay to 2.5 pg/ml in the electrochemical version. This way, the plasma volume of samples containing on the order of 1 ng/ml LH was reduced to less than 10 µL. The linear range was 2.5-625 pg/ml. The method allowed us to measure LH in buffer and in adult and juvenile chicken plasma. Copyright 1998 Academic Press.
Hormone, luteinizing 4-Aminophenol Amperometry Electrode Immunoassay Interferences Immobilized antibody

"High Performance Liquid Chromatographic Determination Of Spectinomycin In Swine, Calf And Chicken Plasma Using Post-column Derivatization"
J. Chromatogr. B 1995 Volume 672, Issue 1 Pages 165-171
N. Haagsna*, P. Scherpenisse, R. J. Simmonds, S. A. Wood and S. A. Rees

Abstract: An HPLC method for the determination of spectinomycin in swine, calf and chicken plasma at 0.1µg/ml or higher is described. The clean-up is based upon ion-pair solid-phase extraction on a High Hydrophobic C18 column treated with sodium dioctyl sulfosuccinate. After elution with methanol, spectinomycin is chromatographed on a Spherisorb SCX column using 0.1 M sodium sulfate solution (pH 2.6)-acetonitrile (80:20, v/v) as mobile phase. Fluorescence detection is at an excitation wavelength of 340 nm and an emission wavelength of 460 nm after post-column oxidation with sodium hypochlorite followed by derivatization with o-phthaldialdehyde. Mean recoveries were 99±2% (n = 6), 99±2% (n = 7) and 104±2% (n = 6) for swine, calf and chicken plasma, respectively, at the 0.1µg/ml level.
Spectinomycin HPLC Fluorescence Post-column derivatization