This drug (by Tocris) is only soluble in DMSO. We can't use more than 5% DMSO, however the drug precipitates when DMSO is mixed with saline. Does anyone have a recommendation for another vehicle (drug to be used in vivo)?
(no warranty) Try to use high-HLB surfactants like Pluronuic F68(poloxamer 188) or F127 (poloxamer407). They are suitable for delivery of some non water-soluble compounds and not very harsh on cells (but of course you will need to test it first).