When pellets containing amino acid alanine are irradiated, stable free radicals are produced in concentration which depends on exposure.

The measured response to microwaves of the pellet placed in a magnetic field of paramagnetic resonance spectrometer, is quantatively related to the radiation dose which the pellet absorbed.


Dose Range

The alanine pellet has a functional dose range of 0.1 to 70kGy (0.01kGy to 100kGy may also be achieved) which makes it ideal for almost any range if irradiation processes.



A white cylindrical pellet of alanine in a wax binder.
90.9% Amino acid L-alpha alanine
9.1% Paraffin wax



Diameter: 4.8mm +/- 0.1mm (5mm to special order)
Height:  2.8mm +/-0.1mm
Mass: 60mg +/-2mg within the overall batch, +/- 0.6mg within a lot. (standard deviation 0.3mg)


Measurement Reproducibility

Mass: CV 0.5%
Irradiation response: CV 0.5% NPL irradiated



Each batch is verified by NPL comparison