A process for isolating and/or identifying at least one active chemical substance from a mixture of active and inactive chemical substances, is characterized by the steps: a) adding a target to said mixture and forming a complex of target and at least one active chemical substance of the mixture, b) separating the complex from the inactive chemical substances of the mixture, and either c) liberating and isolating and/or identifying at least one active chemical substance from the separated complex or d) identifying at least one active chemical substance of the mixture by subtracting from a chromatogram of the mixture of active and inactive chemical substances a chromatogram of the mixture of inactive chemical substances which is obtained after separation of the complex, and possibly liberating and isolating the at least one active substance from the separated complex.