Samples of animal or plant tissue are rarely thin or small enough to allow for full counting efficiency. Homogenization of such samples will allow them to be dispersed into a cocktail, but processing large numbers of radioactive samples by homogenization is not practical. To allow for efficient and consistent counting of tissue samples, tissue solubilizers have been developed. These products contain strong denaturants and other agents, which can dissolve tissues at moderately elevated temperatures.

Counting Tissue Samples

BIOSOL/BIOSCINT

1. Place up to 200 mg of tissue, or 1 ml of blood, in a glass scintillation vial. Ground or minced tissue will dissolve more rapidly. Avoid adhesion of the sample to the bottom of the vial, as this will extend the digestion time.
2. Add 1 ml of Biosol. Agitate gently (do not vortex).
3. Incubate in shaking water bath at 50°C for 1-4 hours, until clear.
4. If necessary (for blood or other pigmented samples) decolorize with 0.2 ml of 30% H₂O₂. Cap loosely and incubate at 50°C 1 hour.
5. Cool to room temperature, add 10 ml of Bioscint and count.

SOLUSOL

1. Place up to 100 mg of tissue, or 0.5 ml of blood, in a glass scintillation vial. Ground or minced tissue will dissolve more rapidly. Avoid adhesion of the sample to the bottom of the vial, as this will extend the digestion time.
2. Add 0.2-0.4 ml of Solusol.  For blood samples, use 1-5 volumes Solusol per volume of sample.   Agitate gently (do not vortex).
3. Incubate at 50°C for 1-2 hours, or at room temperature for 3-5 hours, until clear.  Blood samples may require longer digestions (up to 24 hours in some cases).
4. If necessary (for blood or other pigmented samples) decolorize with 2 volumes of 20% benzoyl peroxide in toluene. Cap loosely and incubate at 50°C 30 minutes. Lightly colored samples may be bleached by UV or sunlight exposure.
5. Cool to room temperature, add 10 ml of Soluscint XR and count.

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