IN-VITRO STUDY OF LECTIN-LATEX CONJUGATES FOR SPECIFIC BIOADHESION

The biological activity of lectin-latex conjugates, prepared by covalent coupling (carbodiimide method) of different lectins (tomato, asparagus pea and mycoplasma) to poly(styrene) latexes, was tested in vitro with pig gastric mucin (PGM). After incubation of the conjugates with PGM, followed by centrifugation, the remaining PGM in the supernatant was measured by HPLC. Rate constants of interaction between PGM and lectin-latex conjugates were determined. At equilibrium, which was reached after 40 min of incubation, between 11.8% and 13.8% of the bulk PGM had interacted with the conjugates. The sugar specificity of each lectin-latex conjugate was demonstrated. The PGM interaction with the lectins seemed to be irreversible. Scatchard plots revealed only one type of ligand/receptor group interaction per lectin for PGM binding by lectin-latex conjugates. The binding capacities for the three lectin-latex conjugates tested ranged between 8.5 and 11.5 mu g PGM per mu g lectin.