Abstract
A new method for the determination of trimethylamine in air was studied and the following procedure was established. Trimethylamine in air was sampled at a flow rate of 2 1/min with a sampling tube, which was a 5 mm i. d. × 20 cm glass tube packed with 4 g of (1630) mesh glass beads coated with 0.2 % tartaric acid. Air in the sampling tube was exchanged for nitrogen gas. The sampling tube was installed in a gas chromatograph (FID). The temperature of the sampling tube was elevated from room temperature to 120°C in 25 s, and immediately 25 μl of 15 % ammonia water was injected into the sampling tube. Trimethylamine desorbed was transferred to a gas chromatograph and determined. In this method, the average recovery of trimethylamine was 99.7% and 3.5 % in the coefficient of variation. Trimethylamine was stable in the sampling tube for 96 h after sampling. This method was applied to the determination of trimethylamine in air of a mouse-breeding room and (9.610.0) ppb of trimethylamine was detected. The lower limit of quantitative determination was 0.2 ppb when 20 1 air was flowed. By this method trimethylamine in air is determined simply, rapidly, and precisely.
