Peak purity

Dear friends,
I have a question regarding the peak purity . in three point peak purity my system show that problem is at Apex means conc. is High. so I want to know that is it acceptable that dilute the sample and show that peak purity ? if yes than how much % of RS it is acceptable. If you dilute the sample than impurity also diluted so it may be BDL and your system show the Peak is Pure
Please clarify it.

Regards,
vikas Parashar

Dear Vikas,
In the test of Related substances some times you can’t get the peak purity of active with in the acceptance criteria due to very high concentration of your active,but you can find the peak purity of your diluted standard (active ingredient only)and you can report it also.But you should have proper justification.

Haresh Donda
Senior Scientist-Analytical Research

[quote=vikasparashar]Dear friends,
I have a question regarding the peak purity . in three point peak purity my system show that problem is at Apex means conc. is High. so I want to know that is it acceptable that dilute the sample and show that peak purity ? if yes than how much % of RS it is acceptable. If you dilute the sample than impurity also diluted so it may be BDL and your system show the Peak is Pure
Please clarify it.

Regards,
vikas Parashar[/quote]

[quote=vikasparashar]Dear friends,
I have a question regarding the peak purity . in three point peak purity my system show that problem is at Apex means conc. is High. so I want to know that is it acceptable that dilute the sample and show that peak purity ? if yes than how much % of RS it is acceptable. If you dilute the sample than impurity also diluted so it may be BDL and your system show the Peak is Pure
Please clarify it.

Regards,
vikas Parashar[/quote]

Lets see how much i understood this Q. if u r talking about Related substance test then it is more likely to check it by high concentration of Active so that Impureties in trace amounts can emerge in chromatogram and active peak appear as cigar peak and all impureties are calculated by area noramalization method. Some times Impureties are generated by giving stress to the sample solution by heat, reactions with 0.1 N HCl and Hypochlorite solutions. This is simply a Qualitative test to check peaks resolution between active and impurity peaks.