Scintillation

... like Mith wrote. In our lab we use tritium-labelled thymidine, which the cells then incorporate into their dna and this can be measured with scintillation counters that measure beta decay. Tritium is a weak radiation source and thus fairly safe to use, yet reliable to measure.

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... of the radiation is low—which contributes to it’s non-penetration—but at the same time, that makes it more difficult to detect. You have to use a scintillation counter of some sort; P-32, by contrast, is easy to detect with a simple geiger counter. 3. Because it is hard to detect contamination ...

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... attracted to amino acids when tested in a radioassay. The bacterium was labeled with P(i), and the disintegrations per minute determined by liquid scintillation counting were proportional to the number of cells accumulating in microcapillaries containing amino acids. Positive chemotaxis was observed ...

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