Investigation of electrochemistry of vitamin K1-lipid emulsion films deposited on electrode surface in the presence and absence of nafion multilayers.

• Main Author: Poh, Hwee Ling.
• Other Authors: Richard David Webster
• Format: Final Year Project
• Language: English
• Published: 2010
• Subjects: DRNTU::Science::Chemistry::Physical chemistry::Electrochemistry
• Online Access: http://hdl.handle.net/10356/40330
• Institution: Nanyang Technological University

Research has shown that nathoquinone in vitamin K1 interacts with H+ and H2O molecules , during its redox reaction; with [H+] and [H2O] affecting the reduction potential. Using cyclic voltammetry technique, this project continues to investigate the electrochemical properties of vitamin K1 in various pH conditions (Britton-Robinson buffer solutions) and at different scan rates with new experimental improvements where nafion and lecithin were used to overcome previous problem of adhering vitamin K1 onto glassy carbon electrode surface. The results obtained show that vitamin K1 in pH3 – 11 undergoes a separate redox reaction mechanism which is different from that in pH13. In pH3 – 11 buffers, a 2 e-/2 H+ transfer occurs while in pH13, a 2 step 1 e-/1H+ each transfer took place and this 2 step reaction gradually changes to assimilate to a 2 e-/2 H+ transfer just like in pH3 – 11; when scan rate increases. The analysis and mechanisms deduced from the results in this experiment are in agreement with the earlier findings on vitamin K1’s electrochemical behavior.