Basic question about PMSF

[Dr Engelbert Buxbaum]

ChenHA wrote:


> We often use PMSF to inhibit serine proteases.  We normally make 100
> mM stock in isopropanol,and used 100 to 1000X dilution.  Other
> solvents apart from methanol and isopronanol  are ethanol and DMSO.

Please do not use DMSO as solvent for the quite toxic PMSF
(acetylcholine esterase inhibitor!). In case of spillage DMSO can easily
penetrate skin and take dissolved substances with it. i-Propanol is a
good choice, cheap, low toxicity and less polar than MeOH or EtOH, so
PMSF is more stable in this solvent.