I am working on a BCS Class II drug and need to run an MTT test. And I cannot dissolve the drug with the allowed concentrations of DMSO. First, I dissolve it in high concentrations of DMSO, and when I dilute it with PBS or cell culture media (w/o FBS), it precipitates immediately. And for formulation purposes, I use CDs to improve solubility. But I need to measure the pure drug's cytotoxicity. So what will be the best recommendation?