Microtube Sealer

CryoProof™ 313 Tube Sealer

Manufacturers of microtubes do not recommend storing them under cryogenic conditions because of the potential of liquefied nitrogen seeping into the tube through the cap. Current methods manually encase the entire tube in a heat shrink tubing using a heat gun. The CryoProof 313 is an innovative and patented tube sealer that automatically heat shrinks a short plastic tubing to seal only the cap of a cryogenic tube, and assures a leak-proof seal in seconds. The seal reduces the potential loss of valuable the samples during cryogenic storage arising from very cool air or liquid nitrogen seeping into the tube, or the release of hazardous samples from the tube.

The CryoProof sealing process is microprocessor controlled, and involves simply placing the tube into a holder, putting a heat shrink tubing over the cap, and pressing a button. A beam of hot air shrink wraps the tubing around the cap as the rotating tube to form a seamless and uniform seal. The temperature of the hot air from the CryoProof is controlled precisely and the beam is focused only on the rotating cap. The result is a more consistent and reliable seal compared to manual sealing using a heat gun and crimping the hot ends of the plastic tubing. By sealing the cap and not the entire tube, you still can place the tubes in their regular racks for easy storage and identification after sealing.


  • Microprocessor controlled for precision and reproducibility
  • Short heating times to seal
  • Seals only the cap for easy storage thereafter
  • Adjustable temperature and time to optimize sealing conditions for a given tube
  • Rotation of the tube during the process ensures a uniform and seamless seal
  • Narrow beam of hot air is directed only at the cap of the tube so that biological
    samples will not be thermally affected
  • Holders to accommodate various tube sizes
  • LOOP button for selecting up to 30 sealing runs
  • STOP button to terminate at any time