(131b) Immobilization and Orientation Controll of Anti-CRP Scfv on a Seuface of Polystyrene Latex Beads and Its Application to Latex-Turbidimetoric Assay
ScFv-immobilized PS latex beads were prepared by the passive adsorption method. Averaged diameter of scFv-PS were significantly increased probably because multi-point interaction of positively-charged PS-tag induced aggregation of PS latex beads which were negatively-charged. On the other hand, latex beads with scFv-PM and scFv-D10 were well-dispersed at the pH between 7.5 and 8.5, while scFv-PM-immobilized latex beads were aggregated at pH 6.5, suggesting that surface charge of scFv-PM-immobilized latex beads might be neutral at this pH which was correspondence to isoelectric point of scFv without PMMA-tag. These results expected that scFv molecules were site-specifically immobilized through the PMMA-tag. ScFv-D10-immobilized latex beads were not aggregated at the pH range between 6.5 and 8.5, suggesting that scFv-D10 molecules were randomly oriented and change in charge density of latex beads was not significant so much because the exposed D10-tag might be caught up on surface charge density which must be reduced by immobilization of scFv.
Â Turbidimetoric assays were performed using both scFv-PM and scFv-D10-immobilized latex beads. Consequently, scFv-PM-immobilized latex beads had wider detection range of CRP, compared with scFv-D10-immobilized latex beads.
Â Thus, scFv-PM-immobilized latex beads developed in the present study will be useful for economic and sensitive detection of biomarkers using latex-turbidimetric assay.