[Detecting nicotine and its metabolite cotinine in human hair with capillary gas chromatography].

OBJECTIVE

To develop a rapid method for determination of nicotine and its metabolite cotinine in human hair with capillary gas chromatography with flame ionization detector.

METHODS

The hair sample was digested by 1.5 mol/L sodium hydroxide solution. The nicotine and cotinine in the hair sample were extracted with a mixed solvent of dichloromethane-methanol (3:1). Aliquot of the extraction solution was vaporized with nitrogen flow and then methanol was added to dissolve the analysts. The analysts were tested with capillary gas chromatography.

RESULTS

The detection limits (signal to noise ratio of 3:1) were 4.3 ng/mL for nicotine and 10 ng/mL for cotinine, respectively. The spiked recoveries were 90.33%-113.1% for nicotine with relative standard deviation (RSD) of 2.1%-7.0% and 92.92%-117.4% for cotinine with relative standard deviation (RSD) of 4.4%-8.9%, respectively.

CONCLUSION

The proposed method is sensitive, simple, easy and rapid. It can be easily extended to large scale applications in tobacco epidemiology studies.