A Sensitive HPLC-ESI-MS-MS Method for the Determination of Cotinine in Urine

Determination of New Long-term Metabolites of Methylprednisolone In Human Urine by HPLC-ESI(-)/MS

Methylprednisolone synthetic corticosteroid (MP, Medrol, Canada 8 mg) was orally administered to healthy male volunteer. Urine samples were collected up to three days post-dose. Ten new metabolites have been identified in addition to the seven ones reported previously. LC-MS analysis have shown well-known 11-keto – 11-hydroxy interconversion and the formation of methylprednisolone 20-hydroxy, 6...

HPLC-ESI-MS/MS of imidazole alkaloids in Pilocarpus microphyllus.

Pilocarpine, an important imidazole alkaloid, is extracted from the leaves of Pilocarpus microphyllus (Rutaceae), known in Brazil as jaborandi and used mainly for the treatment of glaucoma. Jaborandi leaves also contain other imidazole alkaloids, whose pharmacological and physiological properties are unknown, and whose biosynthetic pathways are under investigation. In the present study, a HPLC ...

A sensitive liquid chromatography–electrospray ionization-mass spectrometry (LC–ESI-MS) method for determination of eperisone

spectrometry (LC–ESI-MS) method for determination of eperisone in human plasma using buflomedil as the internal standard (IS) is established. After being made alkaline with saturated sodium bicarbonate solution, plasma samples are extracted with a mixture of diethyl ether–cyclohexane (1:1, v/v) and separated by highperformance liquid chromatography on a reversed-phase C1 8 column with a mobile ...

LC-MS/MS Method for the Determination of 21 Opiates and Opiate Derivatives in Urine

Validated HPLC–MS/MS Method for Simultaneous Determination of Curcumin and Piperine in Human Plasma

Purpose: To develop a sensitive and rapid method for the simultaneous determination of curcumin and piperine in human plasma. Methods: The method was based on high-performance liquid chromatography (HPLC) with electrospray ionization tandem mass spectrometer (ESI-MS/MS) detection in positive ionization mode. The analytes and internal standard were isolated from acidified plasma using liquid–liq...