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Measurement of Ultrafast Vibrational Coherences in Polyatomic Radical Cations with Strong-Field Adiabatic Ionization
Published on: August 6, 2018
FemtoMolar measurements using accelerator mass spectrometry
Mehran Salehpour1, Niklas Forsgard, Göran Possnert
1Ion Physics, Angström Laboratory, Department of Engineering Sciences, Box 534, Uppsala University, SE-751 21 Uppsala, Sweden. mehran.salehpour@teknik.uu.se
Rapid Communications in Mass Spectrometry : RCM
|January 30, 2009
Summary
Accelerator mass spectrometry (AMS) enables ultra-sensitive detection of drugs in body fluids. A novel carbon carrier method allows measurements below 20 femtomolar (fM) in human plasma.
Area of Science:
- Analytical Chemistry
- Biomedical Science
- Pharmacokinetics
Background:
- Accelerator mass spectrometry (AMS) offers ultra-sensitive detection of labeled substances in biological matrices.
- Measuring sub-picomolar (pM) drug concentrations is challenging due to natural carbon-14 (14C) in tissues.
- Existing AMS sample preparation requires milligram quantities, unsuitable for trace amounts.
Purpose of the Study:
- To develop a method for ultra-sensitive quantification of labeled drugs in biological fluids.
- To overcome limitations of natural 14C interference in AMS measurements.
- To enable drug concentration measurements in the femtomolar (fM) range.
Main Methods:
- Separation of labeled drugs from biological matrices using High-Performance Liquid Chromatography (HPLC).
- Application of a carbon carrier method, adding a 14C-deficient compound to HPLC fractions.
- Sample preparation for AMS analysis of composite samples containing trace amounts of labeled drugs.
Main Results:
- Demonstrated concentration measurements below 20 fM in 50 microliter human blood plasma.
- Quantified sub-atmol (amol) amounts of labeled drugs.
- Successfully circumvented natural 14C interference by matrix separation and carrier addition.
Conclusions:
- The developed method enables ultra-sensitive drug quantification in biological fluids at sub-fM levels.
- This technique overcomes the limitations of natural 14C and small sample sizes for AMS analysis.
- The method holds significant potential for pharmacokinetic studies and therapeutic drug monitoring.
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