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Molecular Beam Mass Spectrometry With Tunable Vacuum Ultraviolet (VUV) Synchrotron Radiation
Published on: October 30, 2012
Subattomole sensitivity in biological accelerator mass spectrometry
Mehran Salehpour1, Göran Possnert, Helge Bryhni
1Ion Physics, Angström Laboratory, Department of Engineering Sciences, Box 534, Uppsala University, SE-751 21 Uppsala, Sweden. mehran.salehpour@teknik.uu.se
Analytical Chemistry
|April 22, 2008
Summary
Researchers optimized accelerator mass spectrometry (AMS) for tiny biological samples. This new method allows precise measurement of carbon-14 labeled compounds in trace amounts, crucial for pharmaceutical research.
Area of Science:
- Biomedical science
- Analytical chemistry
- Nuclear physics
Background:
- Accelerator Mass Spectrometry (AMS) is a powerful tool for detecting isotopes like carbon-14.
- Traditional AMS requires significant sample mass (around 1 mg of carbon).
- Analyzing small biological samples presents challenges due to limited material.
Purpose of the Study:
- To adapt AMS for the analysis of very small biological samples (down to tens of micrograms of carbon).
- To improve the sensitivity and quantitation limits for carbon-14 measurements in biological matrices.
- To demonstrate the utility of the optimized method for pharmaceutical research.
Main Methods:
- Utilized a 5 MV Pelletron tandem accelerator at Uppsala University.
- Developed a miniaturized graphitization reactor for sample preparation.
- Applied Accelerator Mass Spectrometry (AMS) to analyze carbon-14 labeled biological samples.
Main Results:
- Successfully analyzed biological samples with as little as tens of micrograms of carbon.
- Achieved routine measurements of carbon-14 labeled molecular markers from femtomole down to a few hundred zeptomole (10^-21 mol).
- Quantitated pharmaceutical substances in human blood at concentrations below 1 picomolar (pM).
Conclusions:
- The adapted AMS method significantly reduces the required sample size for carbon-14 analysis.
- This technique enables highly sensitive detection of labeled compounds in small biological samples without additional separation.
- The optimized method is valuable for preclinical pharmaceutical studies and biomarker research.
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