ISSN:
1435-1536
Keywords:
Key words Polystyrene latex
;
protein coadsorption
;
electro-kinetic
;
colloidal stability
Source:
Springer Online Journal Archives 1860-2000
Topics:
Chemistry and Pharmacology
,
Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics
Notes:
Abstract The latex agglutination immunoassay technique uses polymer colloids as a carrier for the adsorbed proteins to enhance the antigen–antibody reaction. Competitive co-adsorption of IgGaCRP and m-BSA proteins on polystyrene latexes with different functionality (sulfate and sulfonate groups) was carried out looking for the increase in the immunoreactivity and colloid stability of latex–protein complexes. The preferential adsorption of a protein is also studied, comparing both surface types. Regarding the application in the development of a diagnostic test system, it is necessary to study the latex–protein complexes from an electrokinetic and colloid stability point of view. The presence of protein on the surface latex shifts the iso-electric point (i.e.p.) of the latex–protein complexes to pH values near the i.e.p. of the protein which is the majority. Thus by the adsorption of m-BSA we can obtain complexes with the i.e.p. near pH 5 and, therefore, with a significant electrostatic repulsion at neutral pH. Due to the higher surface charge density of the sulfonate latexes there is a higher adsorption of both proteins, which can provide a better colloidal stability (by the adsorption of m-BSA) and a better immunoreactivity (by the adsorption of IgG).
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1007/s003960050072
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