Title of article :
Sampling and determination of volatile organic compounds with needle trap devices
Author/Authors :
Wang، نويسنده , , Aiping and Fang، نويسنده , , Fang and Pawliszyn، نويسنده , , Janusz، نويسنده ,
Issue Information :
روزنامه با شماره پیاپی سال 2005
Pages :
9
From page :
127
To page :
135
Abstract :
In this study, a sorbent was immobilized inside a needle resulting in the development of a needle trap (NT) device. This device was applied to extract organic components from gaseous samples and to introduce an enriched mixture into a conventional gas chromatography (GC) injector. Construction of this simple and integrated sampling/extraction/sample introduction device was optimized by considering different ways to immobilize a sorbent in the needle, packing single and multiple-layer sorbent beds, and applying different desorption strategies into the GC injector. A carrier gas system was modified to minimize the carryover for the needle trap with a sealed tip (NT-1), and a narrow-neck liner was used for the blunt-tip needle trap (NT-2). Breakthrough in the device was investigated by connecting two NT-2 devices in series. The needle trap performed very well as an exhaustive spot sampler, as well as in a time-weighted average (TWA) operation. The linear velocity of the mobile phase has no influence on the sampling rate of the needle trap. Validation results against the standard NIOSH 1501 method using charcoal tubes for indoor air surveys demonstrated good accuracy for the NT approach. The reproducibility of the NT-2 was about 1% for benzene. The detection limits for FID detection and for 25 ml gas sample were 0.23 ng/l, 2.10 ng/l and 1.12 ng/l for benzene, ethylbenzene and o-xylene, respectively.
Keywords :
Gas chromatography , Needle trap devices , Exhaustive extraction , Time weighted average sampling , volatile organic compounds
Journal title :
Journal of Chromatography A
Serial Year :
2005
Journal title :
Journal of Chromatography A
Record number :
1521131
Link To Document :
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