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Lisa M. Killam

Bio: Lisa M. Killam is an academic researcher. The author has contributed to research in topics: Solid-phase microextraction & Detection limit. The author has an hindex of 2, co-authored 2 publications receiving 848 citations.

Papers
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Journal ArticleDOI
TL;DR: The solid phase microextraction (SPME) technique as mentioned in this paper involves exposing a fused silica fiber that has been coated with a stationary phase to and aqueous solution containing organic contaminants.
Abstract: The solid-phase microextraction (SPME) technique involves exposing a fused silica fiber that has been coated with a stationary phase to and aqueous solution containing organic contaminants. The analytes partition into the stationary phase until an equilibrium has been reached, after which the fiber is removed from the solution and the analytes are thermally desorbed in the injector of a gas chromatograph

598 citations

Journal ArticleDOI
TL;DR: In this paper, Solid Phase Microextraction (SPME) was applied to the analysis of benzene, toluene, ethyl benzene and xylenes in groundwater.
Abstract: rn Solid-phase microextraction (SPME) is applied to the analysis of benzene, toluene, ethyl benzene, and xylenes in groundwater. The inexpensive SPME method reduced the sample preparation time by 3-7-fold when compared to purge and trap methods. The relative standard deviation ranged from 3 to 5% for the single-operator relative standard deviation using a methyl silicone fiber. Limits of detection of 1-3 ppb (w/v) were obtained when using a fiber coated with 56-pm methyl silicone film and FID detection. The linear range extended from 15 to 3000 ppb (w/v). Solvents have been completely removed from the sample preparation step.

258 citations


Cited by
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Journal ArticleDOI
TL;DR: An analytical technique is described which combines solvent extraction with gas chromatographic (GC) analysis in a simple and inexpensive apparatus involving very little solvent consumption and is in good agreement with a convective-diffusive kinetic model.
Abstract: An analytical technique is described which combines solvent extraction with gas chromatographic (GC) analysis in a simple and inexpensive apparatus involving very little solvent consumption. A small drop (8 μL) of a water-immiscible organic solvent, containing an internal standard, is located at the end of a Teflon rod which is immersed in a stirred aqueous sample solution. After the solution has been stirred for a prescribed period of time, the probe is withdrawn from the aqueous solution, and the organic phase is sampled with a microsyringe and injected into the GC for quantification. The observed rate of solvent extraction is in good agreement with a convective−diffusive kinetic model. Analytically, the relative standard deviation of the method is 1.7% for a 5.00-min extraction of the analyte 4-methylacetophenone into n-octane.

1,191 citations

Journal ArticleDOI
TL;DR: In this article, a modification of the solid-phase microextraction method (SPME) is proposed to shortens the time of extraction and facilitates the application of this method to analysis of solid samples.
Abstract: Headspace solid-phase microextraction is a solvent-free sample preparation technique in which a fused silica fiber coated with polymeric organic liquid is introduced into the headspace above the sample. The volatilized organic analytes are extracted and concentrated in the coating and then transferred to the analytical instrument for desorption and analysis. This modification of the solid-phase microextraction method (SPME) shortens the time of extraction and facilitates the application of this method to analysis of solid samples. The detection limits of the headspace SPME technique are at ppt level when ion trap mass spectrometry is used as the detector and are very similar to that of the direct SPME technique

1,157 citations

Journal ArticleDOI
TL;DR: The main objective of this contribution is to describe the development of the concepts, techniques and devices associated with solid-phase microextraction as a response to the evolution of understanding of the fundamental principles behind this technique.

740 citations

Journal ArticleDOI
TL;DR: The solid phase microextraction (SPME) technique as mentioned in this paper involves exposing a fused silica fiber that has been coated with a stationary phase to and aqueous solution containing organic contaminants.
Abstract: The solid-phase microextraction (SPME) technique involves exposing a fused silica fiber that has been coated with a stationary phase to and aqueous solution containing organic contaminants. The analytes partition into the stationary phase until an equilibrium has been reached, after which the fiber is removed from the solution and the analytes are thermally desorbed in the injector of a gas chromatograph

598 citations

Journal ArticleDOI
TL;DR: Solid-phase microextraction (SPME) as mentioned in this paper is a sample preparation technique that minimizes the consumption of organic solvents and has been shown to be useful in analytical chemistry.
Abstract: In recent years, much attention in analytical chemistry has been paid to sample preparation techniques, especially those which minimise the consumption of organic solvents One of the most promising of these, solid-phase microextraction (SPME), is presented in both its theoretical and practical aspects Conditions which affect its performance are assessed, as are the problems which may arise from its use Finally, some typical applications are listed, highlighting the method's sensitivity and precision, and the range of samples where SPME can be used successfully

526 citations