Diffusive sampling of methylene chloride with solid phase microextraction.

Cheng-Yao Chen; Chunming Hsiech; Jia-Ming Lin

doi:10.1016/j.chroma.2006.10.033

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Diffusive sampling of methylene chloride with solid phase microextraction.

Cheng-Yao Chen·Chunming Hsiech·Jia-Ming Lin

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Abstract

This study examined the characteristics of a solid phase microextraction (SPME) assembly as a passive sampler to determine the short-term exposure level (STEL) of methylene chloride. Two types of SPME fibers and six sampling-related factors were chosen and nested in an L(18) Taguchi's orthogonal array. Samples were thermally desorpted and analyzed by gas chromatograph equipped with an electron capture detector (GC/ECD). The use of 85-mum Carboxen/polydimethylsiloxane (Car/PDMS) fibers resulted in greater adsorbed mass, which was highly correlated with the product of concentration and sampling time (r>0.99, p<0.0001), than 85-microm polyacrylate fibers. The sampling rate (SR) of the 85-microm Carboxen/polydimethylsiloxane fibers was not significantly affected by variations in relative humidity (0-80%) and coexistent toluene (none to 100 ppm). Variance of sampling rate was predominantly attributed to the diffusive path length (86.4%) and sampling time (5.7%). With diffusive paths of 3, 10 and 15 mm, the sampling rates of 85-microm Carboxen/polydimethylsiloxane fibers for methylene chloride were 1.4 x 10(-2), 7.7 x 10(-3) and 5.1 x1 0(-3)mL min(-1), respectively. The measured sampling rates were greater than the theoretical values, and decreased with increment of sampling time until they came to constant.

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Chromatography, Gas Diffusion Environmental Exposure Methylene Chloride Solid Phase Microextraction Journal Article Research Support, Non-U.S. Gov't

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Cheng-Yao Chen, Chunming Hsiech, Jia-Ming Lin. 2006-11-02. Diffusive sampling of methylene chloride with solid phase microextraction.. https://doi.org/10.1016/j.chroma.2006.10.033

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