Interaction of bacterial endotoxine (lipopolysaccharide) with latex particles: application to latex agglutination immunoassays.
The latex agglutination immunoassay technique uses polymer colloids as carriers for antibodies or antigens to enhance the immunological reaction. In this work, the interaction of a lipopolysaccharide (LPS) of Brucella Melitensis with two conventional latexes has been studied. Some experiments on the physical adsorption of the LPS onto these polystyrene beads have been performed and several complexes with different coverage degrees were obtained by modifying the incubation conditions. Regarding the application in the development of diagnostic test systems, it is advisable to study the latex-LPS complexes from an electrokinetic and colloidal stability point of view. The complexes were electrokinetically characterized by measuring the electrophoretic mobility under different redispersion conditions. The colloidal stability was determined by simple turbidity measurements. Experimental and theoretical data have been employed to study the molecular disposition of the LPS in the latex particle surface to compare with the outer membrane of bacterial cells. Latex complexes covered by different LPS amounts showed high colloidal stability and adequate immunoreactivity that remains for a long time period.
Peula-García
J M
JM
Departamento de Física Aplicada II, Universidad de Málaga, Málaga, 29071, Spain.
Molina-Bolivar
J A
JA
Velasco
J
J
Rojas
A
A
Galisteo-González
F
F
D000327:Adsorption; D000372:Agglutination Tests; D000818:Animals; D000906:Antibodies / Q000097:blood; D017347:Brucella melitensis / Q000737:chemistry*; D004797:Enzyme-Linked Immunosorbent Assay; D006801:Humans; D007118:Immunoassay / Q000379:methods*; D007840:Latex / Q000737:chemistry* / Q000145:classification; D008070:Lipopolysaccharides / Q000737:chemistry*; D046911:Macromolecular Substances / Q000737:chemistry; D008863:Microspheres; D015394:Molecular Structure; D010316:Particle Size; D011137:Polystyrenes / Q000737:chemistry / Q000145:classification
D000906:Antibodies; D007840:Latex; D008070:Lipopolysaccharides; D046911:Macromolecular Substances; D011137:Polystyrenes