Radiocarbon dating and mass spectrometry

In addition to the stable carbon isotopes ¹²C and ¹³C, the atmosphere contains the radioactive isotope ¹⁴C, with a half-life of 5730 years. This isotope is constantly replenished by cosmic radiation. All living beings take up carbon from the atmosphere through their metabolism. Since carbon is constantly replaced, they retain a constant level of ¹⁴C. When they die, the ¹⁴C decays while the amount of stable isotopes remain constant. By measuring the ratio of remaining ¹⁴C to ¹²C a sample can be dated.

As this ratio is typically of the order of 10^-14 for archaeological samples, highly elaborate sample preparation procedures and precise measurements have to be performed to unambiguously determine the age of a sample. Our laboratory has a long-standing expertise in both development and application of these procedures and performs state-of-the-art radiocarbon dating with several thousands of measurements annually for miscellaneous applications.

A variety of complementary techniques have been used in connection with accelerator mass spectrometry in the field of biomedicine, facilitating extreme measurement capabilities. Subsequently, several new interdisciplinary research areas, with unique analytical capabilities, have emerged.

Sensitivity

In pharmacology, we have demonstrated detection of ¹⁴C-marked drugs in human blood in the zeptomole level range (1 zeptomole = 10^-21 mole).

Small samples

Conventional radiocarbon dating requires milligrams of carbon. We routinely measure samples of only a few micrograms.

Microdosing (clinical phase 0 trials)

New drug candidates can be administered directly to human subjects at an early stage to extract important pharmacokinetic data. This provides information on how the drug is absorbed, distributed, metabolized and excreted.

Regenerative medicine

In a long-term collaborative work with Karolinska Institutet we have developed a method to study specific cell types and extract neurogenesis rates for various parts of the human brain, previously not possible.

Forensic Sciences

In collaboration with the law authorities, date of birth and death can be determined for samples such as teeth from deceased individuals.