Abstract:

A method has been developed for the simultaneous determination of benzene, toluene, xylene, styrene, decane, diethylbenzene, undecane, divinylbenzene, dodecane and naphthalene residues in macroporous adsorption resins(MARs). The organic residues were extracted from resin samples by ultrasonic extraction with dichloromethane and analyzed by gas chromatography. The chromatographic conditions were as follows: a DB-624 capillary column (30 m×0.32 mm i.d.,1.8 μm); carrier gas, nitrogen with a flow rate of 2.5 mL/min; column temperature, programmed from 40 ℃ to 200 ℃ at a rate of 14 ℃/min and kept at 200 ℃ for 1 min; flame ionization detector temperature, 250 ℃; injector temperature, 220 ℃; splitless injection, 1 μL. All the 10 organic residues were separated well in 12 min. The recoveries for spiked standards (n=3) were 73.8%-107.9%. The relative standard deviations were 1.3%-4.4%. The limits of detection were 0.007-0.03 mg/L. This method is sensitive, accurate and quick. Nine commercial MARs and their pretreated samples were assayed, and the results show that the contents of organic residues varied greatly in two kinds of samples. And the pretreated MARs can be used safely in the production of traditional Chinese medicines.

Key words: benzene, decane, diethylbenzene, macroporous adsorption resin , naphthalene, organic residues, toluene, gas chromatography