I'm currently working on research on hepatoprotective activity of moringa on tuberculosis drugs induced liver toxicity, Isoniazid combined with Rifampicin by intraperitoneal, but Rifampicin cant seem to dissolve well in saline solution.
I suggest you try distilled water but one may want to look at its polarity when compared to saline. I think distilled water is neutral when compared to other solvents in certain % in distilled water or deionized water (acetone, DMSO, tween 20) which could cause toxicity