title: Surface plasmon resonance-based inhibition assay for real-time detection of Cryptosporidium parvum oocyst.
abstract: A surface plasmon resonance (SPR)-based inhibition assay method using a polyclonal anti-mouse IgM arrayed Cryptosporidium sensor chip was developed for the real-time detection of Cryptosporidium parvum oocysts. The Cryptosporidium sensor chip was fabricated by subsequent immobilization of streptavidin and polyclonal anti-mouse IgM (secondary antibody) onto heterogeneous self-assembled monolayers (SAMs). The assay consisted of the immunoreaction step between monoclonal anti-C. parvum oocyst (primary antibody) and oocysts, followed by the binding step of the unbound primary antibody onto the secondary antibody surface. It enhanced not only the immunoreaction yield of the oocysts by batch reaction but also the accessibility of analytes to the chip surface by antibody-antibody interaction. Furthermore, the use of optimum concentration of the primary antibody maximized its binding response on the chip. An inversely linear calibration curve for the oocyst concentration versus SPR signal was obtained in the range of 1x10(6)-1x10(2)oocystsml(-1). The oocyst detection was also successfully achieved in natural water systems. These results indicate that the SPR-based inhibition assay using the Cryptosporidium sensor chip has high application potential for the real-time analysis of C. parvum oocyst in laboratory and field water monitoring.
authors.affiliation: School of Chemical and Biological Engineering, Seoul National University, Seoul 151-744, Republic of Korea.
authors.forename: Chang Duk
authors.initials: CD
authors.lastname: Kang
authors.forename: Cuong
authors.initials: C
authors.lastname: Cao
authors.forename: Jeewon
authors.initials: J
authors.lastname: Lee
authors.forename: Insung S
authors.initials: IS
authors.lastname: Choi
authors.forename: Byung Woo
authors.initials: BW
authors.lastname: Kim
authors.forename: Sang Jun
authors.initials: SJ
authors.lastname: Sim
mesh_terms: D000818:Animals; D015374:Biosensing Techniques; D001710:Biotin / Q000737:chemistry; D016785:Cryptosporidium parvum / Q000302:isolation & purification*; D033661:Oocysts; D019809:Streptavidin / Q000737:chemistry; D020349:Surface Plasmon Resonance / Q000379:methods*
chemical_list: D001710:Biotin; D019809:Streptavidin