Physical Data
- Radiation: Beta (100% abundance)
- Energy: Max: 157.47 keV; Average 48.8 keV
Half-Life
- Physical: 87.44 days
- Biological: 623 days (unbound); 90 days (bound)
- Effective: 44 - 76 days (unbound)
Range
- 26 cm in air unshielded
External Hazard
- Not an external hazard
Internal Hazard
- Critical Organ: Testis
- Internal uptake results in exposure to the whole body.
Skin & Eye Hazard
- Avoid skin contamination.
Safety Guidelines
- Plexiglas 1 cm thick is recommended as shielding material. Thinner Plexiglas, although adequate to reduce exposure, does not have good mechanical properties.
- Dosimeters cannot detect S-35 beta radiation due to its low energy.
- Wear a lab coat and disposable gloves when working with S-35. Change gloves frequently.
- Avoid direct eye contact - work behind a Plexiglas shield or wear safety glasses.
- Methionine, cysteine and trans-label compounds can form volatiles during storage, thawing and incubation resulting in contamination.
- Radiolytic breakdown may occur during the freezing process and during thawing. As much as 1 mCi of S-35 can be released per 8 mCi vial of
S-35 amino acid. - Source vials should be opened and used in an operating fume hood.
- Vent S-35 amino acid stock vials with an open-ended, charcoal-filled disposable syringe. Activated charcoal has a high affinity for S-35 vapors.
Updated 1/2013