Abstract
The thermodynamics of adsorption of gallic acid (GA, 3,4,5-trihydroxylbenzoic acid) on the hanging mercury drop electrode (HMDE) surface was studied by temperature-dependent stripping voltammetry (TD-SV), at physiological pH 7.4. The thermodynamic parameters, e.g., Gibbs free energy, Δ G ADS, enthalpy, Δ Η ADS and entropy, Δ S ADS, of adsorption have been determined at physiological temperatures 2–40 °C. Chemisorption of the radical species ≡[GA(OH) 2(O −)] is the energetically important reaction. The thermodynamic data show a complex mechanism of adsorption of GA on the electrode surface, which is strongly dependent on temperature. At low-temperatures T < 12 °C, adsorption is controlled by enthalpy, while at T > 22 °C, adsorption is entropy driven. In the temperature range 12 °C and 22 °C, a combined enthalpy–entropy stabilization occurs. A mechanism is proposed which analyses the implication of thermodynamics to the interfacial adsorption of polyphenols with cell membranes under physiological conditions.
Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
