• It t part of analytical method validation

Definition:

Specificity to defined capability  to assess unequivocally the analyte in the presence of components which may be expected to be present. They might be impurities, degradants, matrix, etc.

Here we identify that

Any interference found in sample

Like you made tablet azithromycine in such a case observer

CASE ASSAY by HPLC

Any interference like
Placebo
Blank
Degradent
Solvents
Dilution etc

CASE ASSAY by HPLC

Any interference like

Placebo
Solvents
Dilution
Texture of other impurity

( not affected retention time)

Same case to apply in dissolution test 

If not any interference

( Not affected Main peak RT ) found that say method is specify And go next parameters

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