Saliva samples are frequently used in forensic and medical applications, such as DNA analysis and paternity testing. Proper low-temperature preservation is crucial to maintain the integrity of these samples and prevent DNA degradation. This article discusses the importance, methods, and features of low-temperature preservation cases for saliva samples.

Content

1. Importance of Low-Temperature Preservation

   • DNA Integrity: Saliva contains a high concentration of DNA, making it valuable for forensic and diagnostic purposes. Low-temperature preservation helps prevent DNA degradation, ensuring that the sample remains viable for analysis.

   • Preventing Contamination: Storing saliva samples at low temperatures reduces the risk of bacterial growth, contamination, or other environmental factors that could affect the accuracy of DNA analysis.

2. Methods of Low-Temperature Preservation

   • Freezing: Freezing saliva samples at temperatures of -20°C or lower is a common method of long-term preservation. This ensures that DNA remains stable and can be analyzed even months or years later.

   • Liquid Nitrogen: For highly sensitive samples or when rapid preservation is necessary, liquid nitrogen can be used to freeze saliva instantly, preventing cellular breakdown and DNA degradation.

   • Portable Coolers: For field-based sample collection, portable coolers equipped with ice packs or phase change materials can maintain low temperatures during transport to a laboratory for further analysis.

3. Types of Low-Temperature Preservation Cases

   • Vials with Seals: Saliva samples are often stored in sealed vials, which are then placed in insulated containers. These vials are designed to protect the sample from temperature fluctuations and ensure that it remains secure during transport.

   • Cryovials: Cryovials are specialized containers used for cryogenic storage of biological samples. They are capable of withstanding extremely low temperatures and are often used for preserving saliva samples intended for long-term storage.

   • Cooling Boxes: For transport over longer distances, cooling boxes designed for biological samples offer controlled temperature environments, ensuring that the saliva samples are kept within the required temperature range during transit.

4. Advantages of Using Low-Temperature Preservation Cases

   • Long-Term Storage: Proper low-temperature storage enables saliva samples to be preserved for long periods without degradation, making them available for future analysis.

   • Increased Accuracy: Samples that are stored correctly at low temperatures are less likely to be affected by environmental factors, ensuring more accurate and reliable test results.

   • Reduced Risk of Contamination: The sealed, insulated environments in preservation cases prevent exposure to contaminants, ensuring that saliva samples remain pure and uncontaminated.

5. Compliance and Regulations

   • Regulatory Standards: Low-temperature preservation cases must meet certain standards to comply with forensic, medical, and legal regulations. This includes ensuring the containers are leak-proof, secure, and capable of maintaining the correct temperature throughout storage and transport.

   • Chain of Custody: Proper documentation and labeling are essential to maintain the chain of custody for forensic samples, ensuring that the sample can be tracked from collection to analysis.

Features

• Temperature Control: Maintains optimal storage conditions to prevent DNA degradation.

• Sealed and Secure: Protects saliva samples from contamination during transport and storage.

• Long-Term Preservation: Enables storage of saliva samples for extended periods without compromising integrity.

• Portable Options: Cooling boxes and portable coolers allow for safe transport of samples.

Scope
Low-temperature preservation cases are used in forensic science, medical diagnostics, research, and legal investigations where saliva samples need to be preserved for DNA analysis, disease testing, or paternity verification.