Coupling protein to latex particles having epoxy gps. - for use in immunological analysis esp. pregnancy testing

摘要

Coupling of protein (I) having a reactive gp. which includes a labile H atom., to latex particles of dia. 0.15-1.5 mu comprises reacting at pH 7-9 to form covalent bonds between (I) and free epoxy gps. in the lates. Unfixed (I) is then removed. The latex particles comprise a core, made by (co)polymerising >=1 'hard' monomer, and an outer sheel made by copolymerising >=1 'hard' monomer and an ethylenically unsatd. monomer having free epoxy gps. Both core and shell may include a 'soft' comonomer. Specifically (I) includes NH2 gps., esp. it is human chorionic gonadotropin (HCG), insulin or an enzyme, and the latex is esp. styrene-glycidyl methacrylate. The conjugates are useful in antigen-antibody testing, esp. pregnancy testing. Severe conditions which might denature (I) are avoided; the particles are of uniform size distribution, so are partic. suitable for automated analysis.