Where to store a tick for research? - briefly
Ticks intended for scientific study are best preserved either frozen at –80 °C or immersed in 70 % ethanol stored at 4 °C for short‑term use. The chosen method should match downstream molecular or morphological analyses.
Where to store a tick for research? - in detail
Preserving a tick for scientific investigation requires maintaining DNA, RNA, proteins, and morphology while preventing degradation and contamination. The choice of storage method depends on the intended analyses, duration of storage, and available facilities.
Freezing at ultra‑low temperature provides the broadest compatibility with molecular assays. Specimens placed in cryovials and stored at ‑80 °C retain nucleic acids and proteins for years. For short‑term needs, refrigeration at 4 °C slows enzymatic activity but does not halt degradation; samples should be transferred to colder conditions within 24–48 hours.
Ethanol preservation is suitable for DNA work. Immersion in 70–95 % ethanol, followed by storage at ‑20 °C, dehydrates tissues and inactivates nucleases. Ethanol penetrates quickly, but prolonged exposure can damage protein epitopes, limiting its use for immunological studies.
Commercial stabilization solutions, such as RNAlater, fix nucleic acids at ambient temperature. After submerging the tick in the solution, storage at 4 °C for up to one week, then at ‑20 °C for long‑term preservation, maintains RNA integrity. These reagents are incompatible with downstream histology that requires fresh tissue morphology.
Dry storage of pinned specimens preserves external morphology for taxonomic work. After cleaning and desiccating, ticks are mounted on pins and kept in sealed, low‑humidity containers with silica gel. This method does not support molecular analyses but safeguards diagnostic characters for decades.
When transporting specimens, maintain the selected temperature regime. Use insulated containers with ice packs for refrigerated samples or dry ice for frozen material. Include absorbent pads to contain potential leaks from ethanol or stabilization solutions.
Accurate documentation is essential. Record collection date, geographic coordinates, host information, and storage conditions on a waterproof label attached to each vial or pin. Store metadata in a digital database linked to specimen identifiers.
Regulatory compliance must be observed. Follow institutional biosafety guidelines for handling arthropod vectors, and obtain permits for cross‑border transport if required. Dispose of waste according to hazardous material protocols.
In summary, optimal storage practices include:
- Ultra‑low‑temperature freezing (‑80 °C) for comprehensive molecular work
- Ethanol immersion (70–95 %) plus ‑20 °C for DNA‑focused projects
- RNAlater immersion with subsequent 4 °C and ‑20 °C storage for RNA preservation
- Pinned, dry specimens for morphological taxonomy
- Consistent temperature control during transport
- Detailed labeling and digital record‑keeping
- Adherence to biosafety and permitting regulations
Selecting the appropriate method aligns storage conditions with analytical goals, ensuring sample integrity throughout the research lifecycle.