A rapid therapeutic drug monitoring method of carbamazepine in serum by using coffee ring effect-based surface-enhanced Raman spectroscopy

Carbamazepine (CBZ) has a narrow therapeutic concentration range, and therapeutic drug monitoring (TDM) is necessary for its safe and effective administration. This study aims to develop a procedure for CBZ detection in plasma using coffee ring effect-based surface-enhanced Raman spectroscopy (SERS). Silver nanoparticles deposited onto silicon wafers were used as the SERS-active material. Surface treatment optimization of the silicon wafers and the liquid–liquid extraction method were conducted to eliminate the influence of impurities on the silicon wafer surface and the protein matrix. The proposed detection procedure allows for the fast determination of CBZ in artificially spiked serum samples within a concentration range of 2.5–40 μg·mL –1 , which matches the range of the drug concentrations in the serum after oral medication. The limit of detection for CBZ was found to be 0.01 μg·mL –1 . The developed method allowed CBZ and its metabolites to be ultimately distinguished from real serum samples. It is anticipated that the developed method will have great potential for monitoring other drug concentrations.