The Impact of Low-temperature Centrifugation on DNA

The impact of low-temperature centrifugation on DNA

The impact of low-temperature centrifugation on DNA integrity is mainly reflected in the following aspects:

1. Preventing DNA Denaturation  

   Low-temperature centrifugation helps prevent DNA denaturation. High temperatures can cause the double-stranded DNA to unwind into single strands, while low temperatures help maintain the double-stranded structure of DNA, thereby preserving its integrity.

2. Reducing DNA Fragmentation and Degradation  

   Low-temperature centrifugation can reduce DNA fragmentation and degradation. Although the rate of DNA degradation in solution is not strongly related to temperature, repeated freeze-thaw cycles can accelerate DNA fragmentation and degradation. A low-temperature environment can mitigate this risk, thereby maintaining DNA integrity.

3. Maintaining DNA Molecular Integrity  

   During DNA extraction, maintaining the integrity of DNA molecules typically requires lower centrifugation temperatures. Generally, if a high-speed refrigerated centrifuge is used, the centrifugation temperature is often controlled at around 4°C or lower. This is because low temperatures can prevent DNA denaturation and inactivation, thus preserving its integrity.

4. Preventing Sample Deterioration  

   In certain biological sample separation and preparation experiments, such as the separation of gene fragments, precipitation, and recovery of enzyme proteins, the centrifugation temperature is usually controlled at around 4°C to prevent aggregation, denaturation, and inactivation of the substances to be separated. Low-temperature centrifugation helps prevent sample deterioration, thereby maintaining DNA integrity.

In summary, the impact of low-temperature centrifugation on DNA integrity is primarily reflected in preventing DNA denaturation, reducing DNA fragmentation and degradation, maintaining DNA molecular integrity, and preventing sample deterioration. Therefore, during DNA extraction and separation experiments, it is generally necessary to control the centrifugation temperature at around 4°C or lower.