An on-line SPE-LC-MS/MS method for quantification of nucleobases and nucleosides present in biological fluids.

Solid phase extraction (SPE) and liquid chromatographic (LC) separation of nucleobases and nucleosides are challenging due to the high hydrophilicity of these compounds. Herein we report a novel on-line SPE-LC-MS/MS method for their quantification after pre-column derivatization with chloroacetaldehyde (CAA). The method proposed is selective and sensitive with limits of detection at the nano-molar level.