If you have access to fluorescence equipment, that is probably the most sensitive - and large pi molecules will probably fluoresce.

There are issues - do the adsorbed molecules change in quantum yield and therefore not lie on the same calibration curve as free molecules - but this can be addressed by making up samples of different concentrations for each.

Thank you Prof. James for your suggestion ... Appreciated !

Hi Ahmed, difficult question.

Are you working with multi-walled or single-walled CNT's? Do you know the CNT diameter or length? Does it affect the binding?

Fluorescence is a problem since it is not quantitative.

Can you turn the question around and immobilize your compound and see what CNTs bind to it?