L-DOPA Synthesis Using Tyrosinase Enzyme Precipitate Coatings on the Surface of Electrode

An estimated seven to ten million people worldwide are living with Parkinson's disease. Parkinson’s disease is characterized by a decreased level of the neurotransmitter and dopamine. Levodopa (L-DOPA) is the drug most often prescribed for Parkinson’s disease. This drug is currently chemically synthesized according to a Monsanto process, but the synthesis of L-DOPA suffers from several disadvantages. L-DOPA was synthesized using a tyrosinase enzyme as a biocatalyst for converting L-tyrosine to L-DOPA and an electrochemical method for reducing L-DOPAquinone and the product resulting from enzymatic synthesis to L-DOPA. In this study, three electrode systems consist of glassy carbon electrode (GCE) as working electrode, platinum and Ag/AgCl electrode as auxiliary and reference electrode, respectively. GCE was modified using enzymeprecipitate coating methods to facilitate the electron transfer process and immobilize tyrosinase. Optimum conditions for enzyme precipitate coatings electrode were found to be 30°C and pH 6.5 resulting in L-DOPA concentration of 0.733 mM. After 40 days, relative activity of enzyme for EPC modified electrode remained 73.26%.