[Determination of methylcyclohexanol in workplace air by solvent desorption-gas chromatography]

Objective: To establish a gas chromatography method with solvent desorption for the determination of methylcyclohexanol in workplace air. Methods: In February 2024, the workpace air samples were collected through Neutral silicone tubes, desorbed with ethanol, separated by a polyethylene glycol capillary column modified with nitrophenyl terephthalic acid (DB-FFAP), and then determined by a hydrogen flame ionization detector (FID) . Results: 1-methylcyclohexanol, 3-methylcyclohexanol and 4-methylcyclohexanol show good linear relationships when the mass concentrations are between 1.15-1840.00 μg/ml, and 2-methylcyclohexanol shows good linear relationship when the mass concentration is between 1.16-1860.00 μg/ml (the correlation coefficient r was better than 0.9999) ; the limit of detection (LOD) was 0.23 μg/ml, and the limit of quantification (LOQ) was 0.77 μg/ml, The lowest detection and lowest quantification concentrations were 0.15 and 0.51 mg/m(3) (measured by 1.5 L air sample). The method showed a good average desorption efficiency which was 96.71%-99.47%, and the relative standard deviation (RSD) of within-batches and between-batches were 0.51%-1.25% and 1.20%-2.45%. The air samples could be saved at least 14 d at room temperature and 4 Celsius degree without obvious loss. Conclusion: This method has the characteristics of high precision, high desorbent efficiency, high sensitivity, and simple operation. It is suitable for the determination of methylcyclohexanol in the air in the workplace.