Interaction of Bacterial Endotoxine (Lipopolysaccharide) with Latex Particles: Application to Latex Agglutination Immunoassays

• Published in: Journal of colloid and interface science Vol. 245; no. 2; pp. 230 - 236
• Main Authors: Peula-García, J.M., Molina-Bolivar, J.A., Velasco, J., Rojas, A., Galisteo-González, F.
• Format: Journal Article
• Language: English
• Published: San Diego, CA Elsevier Inc 15.01.2002; Elsevier
• Subjects: Adsorption; Agglutination Tests; Animals; Antibodies - blood; Applied sciences; Biological and medical sciences; Brucella melitensis - chemistry; electrokinetic characterization; Enzyme-Linked Immunosorbent Assay; Exact sciences and technology; General pharmacology; Humans; Immunoassay - methods; Latex - chemistry; Latex - classification; Lipopolysaccharides - chemistry; LPS; Macromolecular Substances - chemistry; Medical sciences; Microspheres; Miscellaneous; Molecular Structure; Organic polymers; Particle Size; particle-enhanced immunoassays; Pharmaceutical technology. Pharmaceutical industry; Pharmacology. Drug treatments; Physicochemistry of polymers; polystyrene latex; Polystyrenes - chemistry; Polystyrenes - classification; Properties and characterization; particle-enhanced immunoassays; polystyrene latex; LPS; electrokinetic characterization; Stability; Liquid solid adsorption; Experimental study; Immunochemistry; Endotoxin; Latex; Intermolecular interaction; Toxin; Brucellaceae; Ionic strength; Electrophoretic mobility; Lipopolysaccharide; pH; Bacteria; Styrene polymer; Molecular complex; Brucella melitensis
• ISSN: 0021-9797; 1095-7103
• DOI: 10.1006/jcis.2001.7958

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.