title: Practical application of a chromogenic FXIIa assay.
abstract: Autohydrolysis of blood factor XII (FXII+FXIIa-->2FXIIa) is found to be a facile reaction in neat-buffer buffer solutions of FXII but an insignificant reaction in the presence of plasma proteins. Autohydrolysis causes a chromogenic assay for FXIIa in buffer solution to strongly deviate from the traditional plasma-coagulation assay. Autohydrolysis can be accommodated by performing chromogenic detection of FXIIa as a rate assay in swamping concentrations of FXII. Rate-assay results performed in this way are shown to be in analytical agreement with the plasma-coagulation assay. Autohydrolysis can be used as a means of amplifying FXIIa produced by contacting neat-buffer solutions of FXII with biomaterials, suggesting a route to highly sensitive measurement of biomaterial hemocompatibility.
authors.affiliation: Department of Bioengineering, University Park, PA 16802, USA.
authors.forename: Rui
authors.initials: R
authors.lastname: Zhuo
authors.forename: Erwin A
authors.initials: EA
authors.lastname: Vogler
mesh_terms: D001681:Biological Assay / Q000379:methods*; D002863:Chromogenic Compounds / Q000737:chemistry / Q000378:metabolism*; D015956:Factor XIIa / Q000737:chemistry / Q000378:metabolism*; D006801:Humans; D006868:Hydrolysis; D010949:Plasma / Q000737:chemistry / Q000378:metabolism; D013223:Statistics as Topic
chemical_list: D002863:Chromogenic Compounds; D015956:Factor XIIa