sample and standard preparation

[jayroseville58]

Scenario Number 1 (Assay Test):

Standard Concentration: 0.12mg/ml
Sample Concentration: 0.15mg/ml

Scenario Number 2 (Dissolution Test):

Standard Conc 1: 0.025mg/ml
Sample Conc 1: 0.028mg/ml

Standard Conc 2: 0.02mg/ml
Sample Conc 2: 0.022mg/ml

In order to calculate the percent dissolved (disso test) and percent label claim (assay test), the standard conc should be equal to the sample concentration. With the above mentioned values, can we accept those difference we made for our standard and sample preparation? Thanks.

[Consumer Products Guy]

I think you're pretty close. One cannot always weigh real samples exactly-enough to make equivalent to 100% of the standard concentration.

We specify in our test procedures "from" and "to" limits for sample weights.