[Determination of p-Anisidine in workplace air by HPLC].

Objective: To establish an HPLC method for determining p-Anisidine in workplace air. Methods: An C(18) capillary column was used with the detection wavelength of 240 nm, the methanol solution (v/v=62:38) as mobile phase, the flow rate was 0.9 ml/min, and the injection volume was 20 µl. Results: The linear range (µg/ml) for p-Anisidine was 0~100; correlation coefficient was 0.999 7; the detection limit was 0.15 µg/ml; the average precision of RSD was 4.4%. The sampling efficiency was more than 95% using silicone tube as sampling filter. Sample can be stored at room temperature for more than 7 d. Conclusion: the method appered to be accurate, simple, sensitive and reliable, also have a high sampling efficiency, and can be usd to determine p-anisidine in workplace air simultaneously.

[Monoamine concentrations in experimental ulcers in rats].

A high performance liquid chromatography with electrochemical detection (HPLC-ECD method was employed for determination of monoamines, including epinephrine (E), norepinephrine (NE), 3,4-dihydroxyphenylacetic acid (DOPAC), dopamine (DA), 5-hydroxy-3-indole acetic acid (5HIAA), homovallilic acid (HVA) and 5-hydroxytryptamine (5HT), in body, antrum and duodenal mucosa of normal rats and rats with MPTP (1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine) induced ulcers. Abundant contents of DA and DOPAC were emerging in normal gastric body, antrum and duodenal mucosa while subsequent reduction of DA concentration were observed in gastric body and duodenal mucosa of rats by MPTP intracerebroventricular injection and persisted for a long time. The degree of reduction was correlated with time and dosage of MPTP administered. The decrease of 5HT in gastric body and its increase in duodenum were also observed at the same time. Such variation of concentrations implied that DA might play an important role in the pathogenesis of ulcerous diseases and 5HT might probably contribute to the development of ulcers.