Sensitive liquid chromatography/tandem mass spectrometry method for the simultaneous determination of nine local anesthetic drugs.

Abstract A high-performance liquid chromatography–tandem mass spectrometry (LC/MS/MS) with electrospray ionization (ESI) procedure for the simultaneous determination of nine local anesthetic drugs (procaine, mepivacaine, lidocaine, ropivacaine, oxybuprocaine, tetracaine, bupivacaine, T-caine and dibucaine) in human serum is described. The chromatographic separation was performed on a Mightysil-RP-18 GP II column (2.0 mm × 150 mm, particle size 5 μm). The mobile phase consisted of 10 mM acetic ammonium buffer (pH 5.4) and acetonitrile and was delivered at a flow rate of 0.20 mL/min. The triple quadrupole mass spectrometer was operated in positive ion mode, and multiple reaction monitoring was used for drug quantification. Solid-phase extraction of the nine local anesthetic drugs added to the human serum was performed with an Oasis ® HLB extraction cartridges column. The method was linear for the investigated drugs over the concentration range of 10–100 ng/mL. The recoveries of these drugs were in the range of 81.4–144%. The standard deviation (SD) values for all analytes were