The best way to do this is by dissolving the compounds or extracts in any other solvent such as methanol and then mixing this solution with DMSO/water. For eg. take 10 mg extract dissolve in 10-30 ul methanol and later dissolve this solution in 2 ml distilled water or DMSO.

Look up the formulation used for Taxol or tamoxifen

Thanks for suggestions. Methanol sometimes causes damage to cells and thereby detachment of adherent cells which leads to faulty results. IF compounds/ extracts are not dissolved in methanol (non-polar compounds) then how to sort out this problem?Any further suggestion.