Radioactive scanning agents with stabilizer

DETAILED DESCRIPTION OF THE INVENTION This invention is based on the discovery that gentisyl alcohol and its phenolate salts and esters (all hereinafter "gentisols") can be utilized to prepare highly stable technetium-99m-based scintigraphic scanning agents.
As known in the art, .
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99m Tc-labeled scanning agents are prepared by mixing a pertechnetate solution with a pertechnetate reducing agent.
It has been found that small amounts of gentisyl alcohol, its salts or esters, can be combined with either the pertechnetate solution or the pertechnetate reducing agent, thereby providing compositions uniquely suited for the preparation of superior, stable .
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99m Tc scanning agents.
There are several compositional aspects to the present invention.
In one aspect, compositions of the present invention comprise a pertechnetate reducing agent which provides a pertechnetate reducing metal or cation, and the gentisol stabilizer.
Such compositions comprise a stabilizing amount of the gentisol stabilizer.
In a second aspect, the compositions of the present invention comprise a pertechnetate solution having dissolved therein a stabilizing amount of the gentisol stabilizer.
When practicing the present invention, it is not critical which compositional form is used to prepare the final technetium-base scanning agent.
Commercial producers of pertechnetate generators may find it desirable to dissolve low levels of the gentisol stabilizer directly into the pertechnetate solution as it is eluted from the generator, or to incorporate a gentisol stabilizer directly on the generator column.
Alternatively, it may be more convenient to combine the gentisol compound with the pertechnetate reducing agent.
In either case, upon combining the pertechnetate solution with the reducing agent and gentisol stabilizer, an improved, highly stable scanning agent is provided.
Gentisol Stabilizer Gentisyl alcohol (chemically: 2,5-dihydroxybenzyl alcohol) is a metabolic product of Penicillium patulum which can be prepared or isolated by several known methods