DMF
(N,N-dimethylformamide) DMF is dried with the addition of approx. 1/3 volume of hygroscopic resin to the storage vessel. For example, AG 501-X8 mixed bed resin (from Bio-Rad) can be placed permanently in the stock DMF bottle. If there is any doubt as to the integrity of the DMF, either add further fresh resin or replace with fresh resin. This issue is a consideration should problems be encountered labeling proteins to a desired ratio. The presence of H2O in the labeling reaction (potentially from the DMF) will compete for the free dye.
