Location: U3202 MRB3
So that the next two answers are obvious to the most frequently asked questions about the Typhoon, I have put them at the beginning.
- No. Our Typhoon CANNOT do fluorescent scans. We have only one red laser at 650 nm which is used for phosphorimaging. The FLA 7000IP can be upgraded in the future to include lasers for dyes such as GFP.
- No. The older, hard-backed Molecular Dynamics screens will not work. Our new Typhoon requires thin, magnetic-backed Fuji BAS-MS or BAS-SR screens sold by GE Healthcare. Please see the datafile for the screens below for specifications. If you would like to order any screens and have questions, please contact the Equipment Manager.
*Note: The information below was taken from the GE Healthcare website pages for the FLA7000 phosphorimager.
How does Storage Phosphorimaging work?
Storage phosphor screens capture latent images produced by ionizing radiation (X-rays, b, and g emissions from isotopes such as 14C, 3H, 125I, 131I, 32P, 33P, 35S, etc.). Upon laser-induced stimulation, light is emitted from the storage phosphor screen in proportion to the amount of radioactivity in the sample. A photomultiplier tube then captures the emitted light and records it on the scan. The resulting digital image allows for quantitation of subtle signal intensity differences over a wide dynamic range using the Typhoon storage phosphor imaging system and the ImageQuant TL software. Typically, 50% to 90% less exposure time is required compared with an equivalent exposure to conventional film. Publication quality images are often obtained in a single exposure.
There is a FLA 7000IP User Guide located on the desktop of the Typhoon computer and is in the link below.
Storage Phosphor Screen BAS-IP comprises a three-layer Phosphorimaging Plate. The photo-stimulatable phosphorlayer contains 5 μm phosphor particles formulated as BaFBr and is sandwiched between a protective layer and a support film uniformly coated with trace amounts of bivalent europium (Eu2+) as a luminescence center.
Additional information can be found by visiting the GE Healthcare screens equipment page.
The questions below are taken from the FAQs section of the GE website.
Q. Can I expose my phosphor screen to -70 degrees C?
A. We do not recommend exposing screens to -70 degrees C. Screens exposed to temperatures below ambient cannot be returned for replacement. Low temperature exposure does not enhance the sensitivity. If you proceed with the low temperature exposure these are the areas of concern:
- Prevent water from condensing on the surface of the screen
- Use -20 degrees instead of -70 degrees.
- Place the wet gel in a Ziplock bag with some desiccant in the bag.
- After exposure quickly remove the gel and avoid exposing the screen to both air and light.
- Put the gel back in the freezer before it melts.
- Leave the screen and cassette in the bag while they warm up to room temperature.
Customers have successfully exposed the screens to minus 20 degrees with no apparent damage, but this is not guaranteed.
Q. How do you clean up after using a storage phosphor scan on the Typhoon?
A. After the Typhoon instrument completes the scan, open the sample lid and remove the storage phosphor screen. Avoid touching the white side of the screen.
After each scan, you should:
- Remove the sample from the exposure cassette and dispose of the sample using the established procedure in your laboratory.
- Check the storage phosphor screen for contamination.
- "Clean" the storage phosphor screen (please read below before you do any "cleaning").
- Erase the storage phosphor screen.
- Check the Image Eraser for contamination and clean the eraser.
- Check the exposure cassette for contamination and clean the exposure cassette.
Store the storage phosphor screen at room temperature. Store the screen away from sources of radiation, such as strong beta or gamma emitters or X-ray machines. Place the screen in a protective box or in a clean exposure cassette. Damaged screens are unusable and must be replaced.
Q. How do you clean the Storage Phosphor screen exposure CASSETTE?
A. The Cassette is NOT the SCREEN. THIS PROCEDURE IS ONLY FOR THE CASSETTE. THE CASSETTE HAS THE GRID LINES ON THE SURFACE.
Immediately before placing the sample in the exposure cassette, clean the grid surface of the cassette with a damp cloth moistened with a small amount of distilled water. If visible spots remain, clean the surface first with 75% ethanol and then with distilled water.
Caution: Do not allow liquid to seep into the exposure cassette. Use a damp cloth only. Do not pour or spray liquid in the cassette.
Q. How do you clean the Storage Phosphor screen?
A. Well, you don't. This is why one should never touch the screens with their bare fingers as the oils will be permanently etched on them. Any largescale wetting of the screens will cause significant deterioration of the crystal lattice over time. If there are buffer crystals on the screen, you might take a Kimwipe LIGHTLY dampened with MQ H2O and brush off the crystals.