Rapid determination of tramadol in human plasma by headspace solid-phase microextraction and capillary gas chromatography-mass spectrometry.

Department of Pharmacy, Fudan University, Shanghai 200032, PR China.
Journal of Pharmaceutical and Biomedical Analysis (Impact Factor: 2.95). 03/2005; 37(1):143-7. DOI: 10.1016/j.jpba.2004.09.050
Source: PubMed

ABSTRACT A simple, rapid and sensitive method for determination of tramadol in plasma samples was developed using headspace solid-phase microextraction (HS-SPME) and gas chromatography with mass spectrometry (GC-MS). The optimum conditions for the SPME procedure were: headspace extraction on a 65-microm polydimethylsiloxane/divinylbenzene (PDMS/DVB) fiber; 0.5 mL of plasma modified with 0.5 mL of sodium hydroxide (0.1 M); extraction temperature of 100 degrees C, with stirring at 2000 rpm for 30 min. The calibration curve showed linearity in the range of 1-400 ng mL(-1) with regression coefficient corresponding to 0.9986 and coefficient of the variation of the points of the calibration curve lower than 10%. The detection limit for tramadol in plasma was 0.2 ng mL(-1). The proposed method was successfully applied to determination of tramadol in human plasma samples from 10 healthy volunteers after a single oral administration.

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