TLC–surface enhanced Raman scattering of apomorphine in human plasma

Apomorphine is a well-known short-acting dopamine agonist typically used in the treatment of patients with advanced Parkinson's disease. In this work we propose a method for detection of apomorphine in blood plasma through Surface Enhanced Raman Scattering (SERS) technique. Detection can be achieved in a few minutes by simply depositing a drop of the blood plasma containing Apofin® on silica Thin Layer Chromatography (TLC) substrates and dropping the silver colloid on it. The Raman measurements carried out on the edges of the stain reveal the presence of the drug through its SERS signal which is found to significantly differ from the normal Raman spectrum. We propose a Density Functional Theory (DFT) model for the interpretation of the major SERS signatures of apomorphine in terms of the interaction of the drug molecule with silver.