Electrochemical activation of human factor XII (Hageman factor) immobilized on carbon electrodes

✍ Scribed by Hyacinthe Randriamahazaka; Jean-Maxime Nigretto

• Publisher: Elsevier Science
• Year: 1993
• Tongue: English
• Weight: 699 KB
• Volume: 283
• Category: Article
• ISSN: 0003-2670
• DOI: 10.1016/0003-2670(93)85286-s

✦ Synopsis

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Direct potential-mediated activation of purified human factor XII @XII) immobilized on carbon electrodes has been evidenced. This required first to find a procedure for the immobilization of FXII on the electrode with good reproducibility. The adsorption isotherms of this xymogen and those of the enxymatic form, FXIIa, were characterized and discussed. The catalytic activities were estimated under stirring with a specific substrate (S-2302) provided with chromogenic properties and dissolved in the solution. Pretreatment of the electrode with negative square-wave potential pulses resulted in changes in the adsorption capacity of the carbon surface towards FXIIa. When the untreated electrode was covered with FXII at saturation, application of these pulses generated catalytic activities according to first-order kinetics.