A spore syringe is a laboratory tool containing microscopic fungal spores suspended in sterile water. These spores are the dormant reproductive units of the fungus. Proper storage is fundamental to preserving their viability—their ability to successfully germinate when introduced to a nutrient source. Maintaining the correct environmental conditions ensures the spores remain contaminant-free and ready for use.
Short-Term Environmental Needs
When a spore syringe will be used within a relatively short period, such as a few days up to one month, refrigeration is not strictly necessary. The primary focus for this short-term storage is maintaining a stable, moderate temperature. An ideal range for ambient storage is typically between 65°F and 77°F (18°C and 25°C), which reflects standard room conditions.
Storing the syringe in a location away from temperature extremes is important because heat can accelerate the spores’ metabolic rate and degrade their cellular structure. Direct sunlight must be avoided entirely, as ultraviolet (UV) light exposure can severely damage the spores’ DNA, reducing their ability to germinate. A dark drawer or cabinet provides a suitable environment, protecting the syringe from light and shielding it from heat sources like radiators or electronics.
Maximizing Long-Term Viability
For storage periods extending beyond one month, or for preservation lasting up to one to two years, cold storage in a refrigerator is the industry standard. This method significantly extends the viability of the spores by slowing their metabolic processes. The optimal temperature range for long-term preservation is consistently cited as 35°F to 46°F (2°C to 8°C).
Temperatures above this range can risk promoting the slow growth of contaminating bacteria or fungi, while conditions below the threshold carry the risk of freezing. Never place a spore syringe in a freezer, since the formation of ice crystals physically ruptures the delicate cell walls of the spores, rendering them non-viable. Within the refrigerator, the syringe should be placed in an area with stable temperature, such as a middle shelf, and kept away from the door, which experiences frequent temperature fluctuations.
Preparation and Post-Storage Handling
Specific handling steps are necessary to maintain the syringe’s integrity before storage. The needle should be recapped and the syringe itself should be sealed within an airtight container, such as a sterile zip-top bag. This protective measure prevents airborne contaminants from reaching the syringe and minimizes the risk of condensation forming on the exterior when refrigerated.
Clear identification is also necessary. Each syringe should be labeled with the fungal species and the date it was prepared.
When using a refrigerated syringe, it should not be used immediately after removal from the cold environment. The syringe must be allowed to acclimate to room temperature slowly over a period of 30 to 60 minutes before inoculation. This gradual warming prevents a sudden temperature shock that could negatively affect the spores’ ability to germinate.