Free DNA preservation solution is a liquid reagent specifically used to preserve free DNA in blood and other samples. In the field of liquid biopsy, free DNA is an important detection object, and its integrity directly affects the reliability of subsequent genetic testing results. The function of free DNA preservation solution is to protect DNA molecules from degradation and contamination during the period from sample collection to detection, maintaining their concentration and structure in their original state.
Design logic and core components of preservation solution
Free DNA preservation solution is a multi optimized protective system designed to maintain the structural integrity of free DNA at its original concentration. To achieve this goal, preservation solutions typically contain several key components.
Buffer solution is the basic component of preservation solution, which is responsible for maintaining the pH stability of the entire system. DNA molecules are prone to deprotonation or hydrolysis reactions in acidic or alkaline environments, and the addition of buffer can effectively resist pH fluctuations caused by the sample itself or external environment. Chelating agents are another important component, and EDTA is the most common choice among them. There are naturally occurring nucleases in blood samples, and the activity of these enzymes often depends on metal ions such as magnesium ions as cofactors. EDTA chelates these metal ions, depriving nucleases of the auxiliary conditions required for their activity, thereby inhibiting the degradation process of DNA.
Protease inhibitors also have a place in the preservation solution. Proteases in the sample may degrade proteins that bind to DNA, indirectly affecting the stability of DNA molecules. Adding protease inhibitors helps maintain the binding state between DNA and proteins, providing indirect protection for DNA. In some formulations, polymerase inhibitors are also added to prevent the consumption or alteration of DNA templates by non-specific nucleic acid amplification reactions that may exist in the sample.
The core function of preservation solution
Free DNA preservation solution achieves protection of free DNA through multiple mechanisms. Inhibiting nuclease activity is one of the most direct pathways. After blood collection, nucleases that were originally separated from blood cells will be released through cellular metabolism or come into contact with free DNA. If not inhibited, nucleases will continue to cleave DNA molecules, resulting in a decrease or even disappearance of the target fragment concentration. The chelating agents and protease inhibitors in the preservation solution jointly reduce the activity of nucleases, providing a relatively safe chemical environment for DNA.
The convenience brought by room temperature storage
Traditionally, the preservation of free DNA relies on low-temperature freezing, and samples need to be placed in an environment of minus 20 degrees Celsius or even minus 80 degrees Celsius as soon as possible after collection. Although this method is effective, it requires a large investment in cold chain equipment, strict transportation conditions, and complex operational procedures. Free DNA preservation solution allows samples to be stored at room temperature for several weeks or even longer without significant degradation. This feature greatly simplifies the process of sample collection, transportation, and temporary storage, especially suitable for application scenarios in multi center clinical trials and primary healthcare institutions.
Precautions during use
Free DNA storage solution should be stored in a dark and cool place, avoiding high temperatures and direct sunlight. It should not be stored frozen, as freezing may cause certain components in the storage solution to precipitate or denature, affecting its protective effect. The storage solution is designed for one-time use, and once mixed with the sample, it should not be reused even if it is not completely used to prevent cross contamination. Before use, carefully read the product manual and operate according to the recommended addition ratio and mixing method. For experimental plans with special requirements, pre experiments can be conducted to verify the compatibility of the preservation solution with the subsequent detection system.
Free DNA preservation solution provides an efficient tool for sample management in liquid biopsy. The free DNA preservation solution produced by Hubei Xindesheng Material Technology Co., Ltd. is suitable for the preservation and transportation of free DNA in blood samples, and can provide a stable sample basis for subsequent genetic testing.
