The target analyte you mentioned 8-hydroxy 2-deoxyguanosine in itself is a reference in ultra pure form. The sample containing the target analyte is to be spiked with the ultra pure internal standard of known concentration which will give rise to commensurate increase in peak area of the target analyte peak in the chromatogram which can be compared with peak area for the sample without spiking.

Colleague Kulkami suggests spiking which might be suitable, depending on your purpose.

For what reason do you need the internal standard?

Is there a loss of your component of interest in sample preparation? What kind of HPLC operational system (column plus mobile phase) are you using. Depeding on the separation mechanism you can select either (and prefered) a similar component or search for something complete different qua structure.

If you have a robust method you might as well think about an external standard, to be used in the beginning and in the end of the series.

Jos P M Wielders sir,

I am working on urine and column is C18. Mobile phases are water (94%) and methanol (6%). System is HPLC-UV (Schimadzu-labsolution).

People prefer similar analog or similar structure of molecule as internal standard but in all case it is not possible. Hence you choose those molecule as internal standard which are not show any type of interaction with your own molecule. Beside of that it need to be optimise instrument parameter with your own compound.

Thanks Mamunur Rashid,

Creatinine is most preferred internal standard for this analyte as I found in most of previous studies.

Okay bahi..Good