▎ 摘　　要

Poly ( 2 , 2-bithiophene-co-5-methoxyindole ) -oxide graphene composite coating was prepared by voltammetry for headspace solid-phase microextraction and gas chromatography determination of antidepressants ( i. e. , citalopram , fluoxetine and nortriptyline ) . The coating was uniform and showed cauliflower-like microstructure. It had high thermal stability ( up to 400 degrees C ) and could be used for at least 180 times of solid-phase microextraction ( SPME ) without decrease in extraction performance. Furthermore , it presented high extraction capacity for the antidepressants due to the hydrogen bond and pi-pi interaction between the analytes and the coating. Under optimized conditions , good linearity ( R > 0. 9958 ) , wide linear range ( 0. 01 - 50 mu g/L) and low limits of detection ( 4. 25 -6. 25 mu g/L ) were achieved for these analytes. The relative standard deviation was less than 5. 3% for five successive measurements with one fiber, and the relative standard deviations for fiber-to-fiber were 4. 8% - 6. 5% ( n =5 ). The SPME-GC method was applied to the determination of lake water, with recoveries of 93.6% -109%.