Ensuring Nucleic Acid Stability in Samples: Comprehensive Guidelines & High-Quality Reagents by ANT BIO PTE. LTD.

In molecular biology research, especially in experiments such as molecular cloning, the stability of nucleic acids (DNA/RNA) in samples is a critical prerequisite for reliable experimental results. Researchers often invest significant time and effort in experiments, only to face failure due to unanticipated nucleic acid degradation. Nucleic acid degradation in biological samples can occur passively or actively due to factors such as nucleases, temperature, pH value, microorganisms, and intrinsic chemical properties. To address this challenge, this article systematically summarizes the types of common experimental samples, their nucleic acid preservation methods, preprocessing procedures, key precautions, and recommends high-performance nucleic acid preservation and extraction reagents from ANT BIO PTE. LTD. to support stable and efficient molecular experiments.

1. Main Types of Experimental Samples

In molecular experiments, the main sample types include purified nucleic acids, tissues, cells, blood, exosomes, and environmental samples. Different sample types have distinct characteristics, requiring targeted preservation methods and operational precautions to ensure nucleic acid stability.

2. Nucleic Acid Preservation Methods and Stability of Different Sample Types

The stability of nucleic acids varies across different sample types and storage conditions. The following table details the preservation methods and stability considerations for nucleic acids in common samples, providing a practical reference for experimental design.

3. Sample Preprocessing Procedures and Key Precautions

Proper preprocessing of samples is crucial for maintaining nucleic acid integrity and ensuring the success of subsequent experiments. The following outlines the preprocessing steps and core precautions for common sample types.

3.1 Tissue Samples

Bulk tissue samples cannot be fully lysed in a short time and generally require preprocessing. Tissue collection should be completed within 30 minutes of tissue excision, and the sampling process should be as rapid as possible. Cut the tissue into soybean-sized pieces in any direction.

3.1.1 Tissue DNA Extraction

Wash fresh tissue samples twice with normal saline and perform the experiment immediately. If the experiment cannot be conducted immediately, snap-freeze the tissue in liquid nitrogen and store it at -80℃.

3.1.2 Tissue RNA Extraction

Cut animal or plant tissue into small pieces, grind in liquid nitrogen or homogenize with a homogenizer, and quickly transfer to a 2mL centrifuge tube containing 1mL Trizol (Cat. No.: abs60154) for immediate experimentation. If the experiment is to be performed later, it is recommended to immerse the sample in RNA Sample Preservation Solution (Cat. No.: abs9268) and store it in a 4℃ refrigerator overnight (overnight storage at 4℃ is mandatory to ensure complete penetration of the RNA Sample Preservation Solution into the tissue), then transfer to a -20℃ refrigerator. Alternatively, grind the tissue in liquid nitrogen, add Trizol, and store at -80℃.

3.2 Cell Samples

3.2.1 Cell DNA Extraction

After collecting and pelleting the cells, snap-freeze them in liquid nitrogen and store at -80℃.

3.2.2 Cell RNA Extraction

1.       Adherent Cells: Aspirate the culture medium completely, add 1mL Trizol per 10cm² culture area, and pipette several times to ensure complete cell lysis, then transfer to a centrifuge tube. Note: The amount of Trizol for adherent cells should be determined by the surface area of the culture dish, not the number of cells. Insufficient Trizol may lead to DNA contamination in the extracted RNA.

2.       Suspension Cells: Collect cells by centrifugation, aspirate the liquid completely, add 1mL Trizol per 5-10×10⁶ animal/plant or yeast cells, or per 1×10⁷ bacterial cells, and pipette to achieve complete lysis, then transfer to a centrifuge tube. Note: Do not wash the cells before adding Trizol to avoid RNA degradation. If necessary, a homogenizer can be used to lyse certain bacterial or yeast cells. If RNA extraction is to be performed later, snap-freeze the cells in liquid nitrogen and store at -80℃.

3.3 Blood Samples

Blood samples can be preserved using vacuum blood collection tubes containing anticoagulants. However, there are various types of anticoagulants, and the choice directly affects subsequent detection results. We recommend using EDTA or sodium citrate anticoagulant tubes; heparin anticoagulant tubes are not recommended (heparin is difficult to remove during nucleic acid extraction and strongly inhibits PCR reactions). After blood collection, invert and mix thoroughly for later use. In addition, during the thawing process of frozen blood, lysed cells will release RNases. Therefore, add Trizol before freezing; do not directly freeze fresh blood. Preserved blood should avoid repeated freeze-thaw cycles.

3.4 Serum/Plasma Samples

Serum is the supernatant separated from whole blood without anticoagulant, while plasma is the supernatant separated from whole blood with anticoagulant. After collecting whole blood, let it stand for 1-2 hours, then centrifuge at 3000rpm for 15 minutes to obtain serum or plasma.

4. Key Tool for Sample Preprocessing: RNA Sample Preservation Solution (abs9268)

RNA Sample Preservation Solution is a non-toxic, ready-to-use sample storage solution that can separate RNA from RNases in cells, preventing changes in the RNA expression profile of samples. RNA in samples stored in RNA Sample Preservation Solution can remain stable at room temperature for 7 days, at 4℃ for 4 weeks, and long-term at -20℃ or -80℃. Samples preserved in RNA Sample Preservation Solution can withstand 20 freeze-thaw cycles to room temperature without affecting RNA quality.

4.1 Operation Steps

1.       Calculate the Amount of Preservation Solution: Based on the volume of each sample to be preserved, calculate the required amount of RNA Sample Preservation Solution: a) The amount of RNA Sample Preservation Solution should be 10 times the tissue volume (approximately 1mL of RNA Sample Preservation Solution for 100mg of tissue); b) The amount of RNA Sample Preservation Solution for 2×10⁷ centrifuged cells is 1mL.

2.       Aliquot: Aliquot the required amount of RNA Sample Preservation Solution into self-prepared storage tubes.

3.       Section: Quickly cut larger tissues into arbitrary slices with a thickness of ＜0.5cm; take smaller tissues directly and immediately immerse them completely in RNA Sample Preservation Solution.

4.       Preserve: First immerse the sample in RNA Sample Preservation Solution and store it in a 4℃ refrigerator overnight, then transfer to a -20℃ refrigerator or further to a -80℃ refrigerator.

5. Recommended Products by ANT BIO PTE. LTD.

To support researchers in effectively ensuring nucleic acid stability and improving experimental efficiency, ANT BIO PTE. LTD. provides a series of high-quality nucleic acid preservation and extraction reagents that have undergone strict quality control and verification. The detailed product information is shown in the following table:

6. Brand Mission

ANT BIO PTE. LTD. is committed to advancing molecular biology research by providing high-quality, reliable nucleic acid preservation and extraction reagents, as well as comprehensive experimental solutions. Our product portfolio, including RNA Sample Preservation Solution, Tissue Preservation Solution, RNase Inhibitor, and Trizol, is carefully developed and optimized to address the pain points of nucleic acid degradation in sample preservation and preprocessing, ensuring the integrity and stability of nucleic acids for researchers.

Guided by the principles of innovation, quality, and customer-centricity, our three specialized sub-brands (Absin, Starter, and UA) cover a full spectrum of research needs, from basic sample preservation reagents to specialized nucleic acid extraction kits. We strive to establish long-term and trusted partnerships with researchers worldwide, supporting them in achieving breakthroughs in molecular biology research and contributing to the development of fields such as genetics, oncology, and immunology.

7. Disclaimer

This article is compiled and interpreted based on relevant core content. All intellectual property rights related to the original content belong to the corresponding author. For any infringement, please contact us promptly and we will take immediate action.

8. Brand Promotion Copy

ANT BIO PTE. LTD. – Safeguarding Nucleic Acid Integrity, Empowering Research Success

At ANTBIO, we are dedicated to advancing molecular biology research through high-quality, reliable nucleic acid preservation and extraction reagents. Our comprehensive product portfolio, including RNA Sample Preservation Solution, Tissue Preservation Solution, and RNase Inhibitor, effectively prevents nucleic acid degradation, ensuring the stability and integrity of samples throughout preservation and preprocessing. Backed by professional technical expertise, we strive to be your trusted partner in overcoming experimental challenges. Explore our product portfolio today and lay a solid foundation for your molecular biology experiments.