Abstract:

Objective To establish a headspace arrow solid phase microextraction combined with gas chromatography-mass spectrometry（SPME-GC-MS） for the determination of 2，5-hexadione in urine，to provide a more efficient，simple and sensitive method for the detection of urine samples in people with occupational exposure to n-hexane. Methods 4 mL urine samples were collected in a headspace bottle，added salting agent，sealed and loaded on the machine. After separation by chromatographic column，SIM scanning was performed qualitatively and external standard method was used for quantization. Results After the column type，the amount of salting agent added and the conditions of arrow headspace solid phase microextraction were optimized，HP-INNOWax column was selected，1.5g NaCl was added，the preheating temperature was 60 ℃，and the extraction time was 30 min. The linearity of 2，5-hexanedione in urine was good in the concentration range of 0.05-5.00 μg/mL，and the correlation coefficient was 0.997 2. The limits of detection and the limits of quantification were 0.01 and 0.03 μg/mL，respectively. The relative standard deviation of precision test was 2.07%-6.19%，and the recovery rate of urine samples was 83.98%-97.62%. The method was used to test the urine samples of 8 occupational n-hexane contacts，and low concentration was detected in 5 of them. The experiment showed that this method had high sensitivity，and the results were accurate and reliable.Conclusion Compared with the liquid-liquid extraction method in the hygiene standard WS/T 243-2004 "Biological limit values for occupational exposure to n-hexane"，the established SPME-GC-MS for the detection of 2，5-hexandione in urine greatly simplifies the experimental procedure，and the pretreatment is simple and rapid，which can eliminate the interference of complex urine matrix，and can be used for urine sample detection and analysis in occupational exposure to n-hexane.

Key words: Headspace arrow solid phase microextraction, Gas chromatography-mass spectrometry, Urine, 2, 5-hexanedione