Validation of Sterilization Process by Gamma Radiation

The Laboratory of Technological Assays in Clean Environment (LETAL) provides to the community the unique national service of evaluation of gamma radiation as a sterilization process for health care products, namely medical devices, active principles, raw materials and packaging.

This service allows to estimate the microbial bioburden of the product; the minimal radiation dose (Dmin) to attain the sterilization of the product; and for some products the maximum radiation dose (Dmax) that the product can tolerate without degradation, using spectrometric and chromatographic technics.

The Validation of the Sterilization Dose by Gamma Radiation service is based on the International Standard ISO 11137. Our consulting services can guide you to evaluate the best approach to lower the microbial contamination of your product in order to permit the validation of the sterilization by gamma radiation.

We work closely with industry and other academic groups to evaluate the extent to which gamma radiation methods can be used as sterilization processes that guarantee the Safety and Quality of different kinds of products.

Further information:

Doctor Sandra Cabo Verde 

: +351-21-9946253
Email: 

Radiocarbon Dating Services

The C²TN Radiocarbon Dating Laboratory is a unique research facility in Portugal, providing dating services in a large diversity of research areas such as Archaeology, Anthropology, Palaeoceanography, Quaternary Geology, Isotope Hydrology and Palaeoenvironmental Studies.

The analytical services comprise the absolute dating of organic samples using radiometric measurements by liquid scintillation counting (Benzene Method). Common samples include wood, charcoal, bone, shell, seeds, peat and organic sediments with a maximum age of about 50,000 years. The optimal sample weight for radiocarbon dating with the Benzene Method equals 5 g of carbon (circa 10 g of wood/charcoal; 150 g of shells; 200 g of bones; considering dry samples without contaminants). Smaller samples can also be dated although the precision may be affected. The usual turnaround time for delivery of results is 6 to 8 weeks.

The C²TN Radiocarbon Dating Laboratory is continuously involved in research projects and operates closely with clients providing technical services to public and private institutions, regional and local governments, universities and other research groups.

Further information:

M. Fátima Araújo () - Pedro Valério ()

: +351-21-9946000