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Updated: Jun 1, 2026
09:42
Fabrication of a Dipole-assisted Solid Phase Extraction Microchip for Trace Metal Analysis in Water Samples
Published on: August 7, 2016
Water analysis by solid phase microextraction based on physical chemical properties of the coating
A Saraullo1, P A Martos, J Pawliszyn
1The Guelph-Waterloo Centre for Graduate Work In Chemistry, Department of Chemistry, University of Waterloo, Waterloo, Ontario, Canada N2L 3G1.
Analytical Chemistry
|June 7, 2011
Summary
A new method quantifies petroleum hydrocarbons in water using solid phase microextraction (SPME) and linear temperature-programmed retention index (LTPRI). This technique estimates partition coefficients, enabling accurate analysis of contaminants like BTEX.
Area of Science:
- Analytical Chemistry
- Environmental Science
- Separation Science
Background:
- Accurate quantification of petroleum hydrocarbons in water is crucial for environmental monitoring.
- Traditional methods can be complex and time-consuming.
- Development of simpler, more efficient analytical techniques is needed.
Purpose of the Study:
- To develop a novel and simple method for quantifying petroleum hydrocarbons in water.
- To establish partition coefficients (K(fw)) for various hydrocarbon classes using SPME.
- To correlate K(fw) with linear temperature-programmed retention index (LTPRI).
Main Methods:
- Solid Phase Microextraction (SPME) with poly(dimethylsiloxane) fiber coating.
- Linear Temperature-Programmed Retention Index (LTPRI) for analysis.
- Determination of partition coefficients (K(fw)) for aromatics, cycloalkanes, and alkanes.
- Utilizing Henry's law coefficients to estimate K(fw).
Main Results:
- A linear relationship was observed between log K(fw) and LTPRI for different hydrocarbon series.
- The slope of this relationship was consistent across all series, linked to hydrocarbon-fiber interactions.
- The y-intercept varied by hydrocarbon group, correlating with Henry's law coefficients.
- The method was successfully applied to quantify BTEX in contaminated water samples.
Conclusions:
- The developed SPME-LTPRI method provides a simple and effective way to quantify petroleum hydrocarbons in water.
- Partition coefficients can be reliably estimated using Henry's law coefficients and LTPRI.
- This approach offers a valuable tool for environmental analysis of hydrocarbon contamination.
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