this is nothing new.
Biotechniques 2000 Sep;29(3):536-8
Extended stability of restriction enzymes at ambient temperatures.
Clark J, Harrison JC, Mdegela RH, March JB.
Moredun Research Institute, Penicuik, Scotland, UK.
The stability of restriction enzymes as supplied by manufacturers without
any modification has been examined. No reduction in activity was observed
for three enzymes (HindIII, EcoRI and Tsp509I) held at ambient temperature
or 4 degrees C for the period of study (12 months), while activity was
observed for up to 12 weeks after storage at 37 degrees C, which was
considerably better than following desiccation with trehalose, a recognized
preservation technique. A larger trial of 23 different restriction enzymes
held at room temperature for one week showed that all enzymes retained
significant activity. As a practical demonstration of the usefulness of this
finding, enzymes were posted to Africa by conventional mail (cost $1 US) and
shown to retain activity upon arrival after three weeks in transit (compared
to a cost of $1000 US by cold-chain transportation). Supplying enzymes to
third-world markets should now be possible by removing the necessity for
cold-chain transport. After arrival, enzymes can simply be stored in a
standard domestic refrigerator.