How to store spore syringes: shelf life, temperature and what actually degrades them
A spore syringe is a stable specimen if you treat it like one. Most of the questions we get about "dead" syringes come down to heat, light or a cap left off. Here is what matters, what does not, and how the library stores its own stock.
01The three things that matter
- Temperature. Store at 2 to 8 degrees, the ordinary fridge range. Spores tolerate cool storage for a long time; they do not tolerate a warm windowsill or a car in summer.
- Light. UV degrades spores. Keep syringes in their sleeve, a box or a drawer inside the fridge.
- The seal. A capped luer-lock tip keeps the water sterile. A syringe left uncapped, even briefly, invites bacteria that will show up on your next slide.
02Should you freeze a spore syringe?
No. Water expands as it freezes and ice crystals damage the spores. A freezer is the one place a syringe should never go. Refrigeration is enough; if you need decades of archival storage, the format for that is a dried print, sealed, not a suspension.
Most of the questions we get about "dead" syringes come down to heat, light or a cap left off.
03How long a syringe keeps
Refrigerated, capped and dark, a syringe from a well-prepared print stays a useful microscopy specimen for many months and often a good deal longer. There is no hard expiry; what changes over time is the proportion of intact spores and, in a poorly made syringe, the amount of bacterial growth. Under the objective an aged specimen shows more debris and more empty spore walls. A fresh one shows clean, full, evenly suspended spores.
MycoWorld prepares syringes to order in small batches, logs the LOT, and refrigerates stock from the moment it is filled to the moment it is packed. That is why the LOT date on your syringe is recent.
04Signs a specimen has degraded
- Cloudiness that looks milky rather than a fine even haze, or strands and clumps that were not there before: bacterial growth.
- A strong smell on opening: contamination.
- Colour changes in the water: contamination or light damage.
- Under the microscope, a high proportion of empty or collapsed spore walls: age or heat.
A syringe showing any of these belongs in the bin, not on your slide. MycoWorld replaces any specimen that arrives compromised; send a photo and the LOT number.
05A simple storage routine
Keep a labelled box in the fridge. Store syringes tip-up in their sleeves, note the LOT and the date received in your notebook, and take a slide from each new arrival within the first week so you have a baseline to compare against later. That is the whole discipline, and it is the same one the library uses.
Specimens for this story: MRRL (Melmak Revert), Project Bluebook (CG isolation), MFH Ape and Albino Saturn Tidepool, all prepared under sterile protocol and LOT-logged in the UK.
Questions people ask
Can I store spore syringes at room temperature?
For a few days in transit, yes. For anything longer, the fridge. Warmth is the main cause of degraded specimens.
How long do MycoWorld syringes last?
Refrigerated, capped and dark, many months and often longer. Every syringe is LOT-logged and prepared to order, so the date on it is recent.
My syringe has been in the fridge for a year. Is it still usable for microscopy?
Very likely. Take a slide: clean, full spores mean it is fine; mostly empty walls and debris mean it has aged past usefulness.