Dimethyl sulfoxide , solubility DMSO stock solutions

In recent years, a great diversity of structurally well-defined functionalized fullerenes has been designed and synthesized for that purpose. Some of them exhibit pronounced solubility in water (vide infra). But even for compounds being virtually insoluble in water, stable aqueous phases can be obtained in plenty of cases by diluting stock solutions of the compounds in polar organic solvents with various amounts of water. Notably, dimethyl sulfoxide (DMSO) and tetrahydro-furan (THF) have turned out to be excellent surfactants for preparing stable aqueous fullerene solutions (Angelini et al., 2005 Cassell et al., 1999 Da Ros et al., 1996 Gun kin et al., 2006 Illescas et al., 2003). Also cosolvents such as dimethylforma-mide (DMF) and methanol can be used to promote water solubility. After subsequent dilution of a saturated solution of C60 in benzene with THF, acetone and finally water, actually stable aqueous suspensions of pristine fullerene can be obtained (Scrivens et al., 1994). 

Because cannabinoids generally have very low water solubility, a non aqueous vehicle is required. Cannabinoids are generally stored at -20 C in ethanol (usually 1 mg/mL) or in dimethyl sulfoxide (DMSO for more details see Note 1). If, like anandamide, a compound is particularly prone to oxidation, its ethanolic stock solution is stored under argon. For addition to organ baths in this laboratory, any ethanol is removed by evaporation, and cannabinoids are dispersed in Tween-80 and saline (14) or dissolved in DMSO (see Note 1 and Table 1). 

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