Preparation of a pure sample for bioassay

Preparation of a pure sample for bioassay (3). pheromone of the palaearctic bee, Andrena wilkella... 

A. Possibly. A substance known as divinorin C has been recently reported by Valdes et. al to be behaviorally active in mice at even lower dosage than salvinorin A. Divinorin C is closely related chemically to salvinorin A and is present in his Salvia extracts in 1/9 the concentration of salvinorin A. It may contribute to the psychoactive effects of Salvia leaves. Divinorin C has never been bioassayed in humans due (among other reasons) to the difficulty in preparing pure samples in significant quantity for such bioassay. A few other salvinorin like compounds are known to be present in Salvia and may also contribute to its psychoactivity. However, salvinorin A is the only Salvia divinorum compound presently known to be psychoactive in humans. 

Accuracy In terms of bioassay, the accuracy of an assay is given by the percentage recovery of the pure substance that was added to the sample before the assay was done. In normal practice the hormonal content of an afiquot of a sample of plasma is first determined. Then a known amount of a standard preparation of the hormone (e.g. 100mUml ) is added to the sample and a second aliquot is assayed. If, for example, the first sample was assayed at 10 mU ml and the second at 105 mU ml the percentage recovery was 95%. 

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