IPTG

Make a 1M IPTG stock solution like so: The molecular weight of IPTG is 238.298 g/mol.

1g IPTG dissolved in water to a total volume of 4.2 mL will give 0.5M final concentration.

The easiest way to do this is to add 2-3 ml water to 1 g IPTG in a 15 mL Falcon tube. dissolve and add water to the 4 mL mark and then add 200 µL with a P1000 pipette.

Filter the solution through a small 0.2 µM filter into several eppendorf tubes ~ 0.5 mL in each. Freeze the aliquots at -20C.