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Updated: Aug 4, 2026
09:42
Fabrication of a Dipole-assisted Solid Phase Extraction Microchip for Trace Metal Analysis in Water Samples
Published on: August 7, 2016
Development of a generic method to the solid-phase extraction of acidic compounds from complex matrices
D M Boland1, M F Burke, T Mitchell
1Department of Chemistry, University of Arizona, Tucson 85721, USA.
Journal of Analytical Toxicology
|October 16, 2001
Summary
This study developed a mixed-mode solid-phase extraction method for purifying acidic drugs from urine. The method achieved over 80% recovery, demonstrating its effectiveness for complex biological samples.
Area of Science:
- Analytical Chemistry
- Pharmacology
- Biochemistry
Background:
- Isolation and purification of acidic compounds from biological matrices are challenging.
- Existing methods may lack efficiency or specificity for acidic drug analysis.
Purpose of the Study:
- To develop and optimize a mixed-mode solid-phase extraction (SPE) procedure.
- To enhance the isolation and purification of acidic compounds from complex biological samples, such as urine.
Main Methods:
- Utilized Isolute HAX mixed-mode SPE columns combining hydrophobic and ion-exchange properties.
- Optimized conditioning, sample loading, rinsing, and elution steps using specific buffers and solvent ratios.
- Analyzed eluted acidic drugs using high-performance liquid chromatography (HPLC).
Main Results:
- Achieved absolute recoveries exceeding 80% for most tested acidic drugs at 1 microg/mL.
- Demonstrated superior analyte retention and extract purity compared to separate hydrophobic or ion-exchange sorbents.
- Identified acetate as a crucial counter-anion for optimal retention on anion-exchange columns.
Conclusions:
- The developed mixed-mode SPE procedure is effective for purifying acidic compounds from biological matrices.
- The choice of counter-ion significantly impacts the retention of acidic analytes in SPE.
- This method provides a robust approach for the analysis of acidic drugs in complex samples.
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