Spectroscopic investigations of human serum fibrinogen and magnetic iron (III) oxide nanoparticle interactions under normal and oxidative stress conditions

Authors

Valdez Rahming, College of Saint Benedict/Saint John's University

Document Type

Thesis

Publication Date

2012

Disciplines

Chemistry

Abstract

The interactions of magnetic nanoparticles (MNP) with human serum fibrinogen and the effects of protein oxidation on binding affinity were investigated by UV-Vis, IR, fluorescence, and circular dichroism spectroscopy. Results indicated that MNP quench fibrinogen fluorescence mainly by a static quenching mechanism. The fluorescence quenching constants (K_sv) were determined as 1.60 x10⁶ M^-1 and 1.06 x10⁶ M^-1 at 300 K and 310 K respectively. The thermodynamic parameters of enthalpy change (ΔH^o_­­), entropy change (ΔS^o_­­), and free energy change (ΔG^o) were – 23.37 kJ mol^-1, 40.00 J.mol^-1 and - 35.31 kJ. mol^-1 (at 300 K) respectively. The formation of fibrinogen-MNP complex caused mild changes in the secondary structure of the protein. Metal catalyzed oxidation of fibrinogen resulted in significant changes in the secondary structure and adversely affected its binding affinity for MNP. After 4 hours of oxidation, the binding constant (K_a) of the fibrinogen-MNP interaction showed a four- fold decrease compared to that of unoxidized protein.

Comments

Advisor: Md Abul Fazal, Faculty Evaluator and co-advisor: Henry V. Jakubowski, Faculty Evaluator: Brian Johnson

Recommended Citation

Rahming, Valdez, "Spectroscopic investigations of human serum fibrinogen and magnetic iron (III) oxide nanoparticle interactions under normal and oxidative stress conditions" (2012). Chemistry Student Work. 2.
https://digitalcommons.csbsju.edu/chemistry_students/2