Nuclease-free water is water that has been deionized, filtered, autoclaved, and tested for contaminants, such as endonucleases, exonucleases, and RNases. This water is rigorously tested to be certified nuclease-free, which includes DNases and RNases.
Nuclease contamination in reagents used for nucleic acid isolation and analysis can contribute to experimental inconsistency and sometimes even experimental failure. In trying to pinpoint the sources of contamination, it is easy to overlook the water used either to prepare reagents or to resuspend precipitated RNA.
Even purified water can have a high pH and minerals that can interfere with reactions that require specific salt and pH conditions. We offer several brands and grades of nuclease-free water—diethyl pyrocarbonate (DEPC)-treated water, nuclease-free water (not DEPC-treated), RT-PCR grade water, and UltraPure distilled water. All have been rigorously tested for contaminating non-specific endonucleases, exonucleases, and RNase activity.
Maintaining an RNase-free lab Nuclease-free buffers and reagents
What is the difference between nuclease free water and distilled water?
The difference between nuclease free water and distilled water is nuclease-free water is specifically treated and tested to be free of nucleases. While both distilled water and nuclease-free water are high-purity forms of water, nuclease-free water is more suitable for applications that require the protection of nucleic acids from degradation.
Diethyl pyrocarbonate treated water
Diethyl pyrocarbonate (DEPC) treated water contains a chemical used to inhibit RNases. DEPC-treated, nuclease-free water should have the following features:
- Autoclaved, membrane-filtered
- Tested RNase- and DNase-free water
- Autoclaved pre- and post-packaging for inactivation of DEPC
Membrane-filtered water and autoclaved for DEPC inactivation
Autoclaving alone may be sufficient to inactivate a substantial amount of RNase enzyme, depending on the downstream applications. However, if your downstream assays are sensitive, DEPC-treated nuclease-free water is a better option. It is added to the deionized water, which is then autoclaved, inactivating the chemical DEPC.
Why is DEPC treated water not recommended for PCR?
DEPC-treated water is not recommended for PCR because the diethyl pyrocarbonate chemicals can interphere with the PCR reaction by inhibiting the DNA polymerase activity.
While DEPC-treated water is effective for inactivating RNases and is useful for RNA-related experiments, it is not recommended for PCR due to the potential presence of residual DEPC and its by-products, which can inhibit the PCR enzymes and compromise the reaction. Instead, nuclease-free or PCR-grade water should be used for PCR to help ensure optimal performance and reliability.
Nuclease-free water (non DEPC-treated)
Our non DEPC-treated, nuclease-free water has the following features:
- Not DEPC-treated: well-suited for applications that may be acutely sensitive to residual DEPC (i.e., oocyte injection)
- Autoclaved, membrane-filtered
- Tested RNase- and DNase-free water
Membrane-filtered and autoclaved water
Non DEPC-treated, nuclease-free water has been autoclaved, specifically for elimination of RNases and DNases. DEPC-treated water is a great option when DEPC presence is irrelevant. However, for some downstream applications, such as oocyte injection or experiments that involve Tris buffer, DEPC treatment is not recommended. Tris contains an amino group which inactivates DEPC, making it unavailable to inactivate RNases.
Nuclease-free water for PCR
Nuclease-free water for PCR should be certified nuclease-free (RNases and DNases), and free of any nucleic acid contamination, such as genomic DNA, that can lead to false RT-PCR signals.
Our nuclease-free water for PCR has the following features:
- RT-PCR-grade water: well-suited for use in any PCR or RT-PCR application
- Each lot tested for nuclease contamination
- Autoclaved, membrane-filtered
- RNase- and DNase-free, genomic DNA-free
Why is nuclease free water used in PCR?
Nuclease-free water is used in PCR to prevent the degradation of nucleic acids and avoid non-specific amplification.
PCR reactions involve small volumes and low concentrations of DNA so even trace amounts of nucleases can significantly impact the integrity of these samples. Using nuclease-free water helps maintain the integrity of the DNA throughout the PCR process.
DNase- and RNase-free water
DNase- and RNase-free water is also known as UltraPure water. UltraPure distilled water is quality tested and no DNase, RNase, or protease activity is detected.
Our UltraPure water has the following features:
- Tested RNase- and DNase-free water, also protease-free
- Autoclaved and 0.1-µm membrane-filtered
- Designed for use in all molecular applications
Diethyl pyrocarbonate treated water
Diethyl pyrocarbonate (DEPC) treated water contains a chemical used to inhibit RNases. DEPC-treated, nuclease-free water should have the following features:
- Autoclaved, membrane-filtered
- Tested RNase- and DNase-free water
- Autoclaved pre- and post-packaging for inactivation of DEPC
Membrane-filtered water and autoclaved for DEPC inactivation
Autoclaving alone may be sufficient to inactivate a substantial amount of RNase enzyme, depending on the downstream applications. However, if your downstream assays are sensitive, DEPC-treated nuclease-free water is a better option. It is added to the deionized water, which is then autoclaved, inactivating the chemical DEPC.
Why is DEPC treated water not recommended for PCR?
DEPC-treated water is not recommended for PCR because the diethyl pyrocarbonate chemicals can interphere with the PCR reaction by inhibiting the DNA polymerase activity.
While DEPC-treated water is effective for inactivating RNases and is useful for RNA-related experiments, it is not recommended for PCR due to the potential presence of residual DEPC and its by-products, which can inhibit the PCR enzymes and compromise the reaction. Instead, nuclease-free or PCR-grade water should be used for PCR to help ensure optimal performance and reliability.
Nuclease-free water (non DEPC-treated)
Our non DEPC-treated, nuclease-free water has the following features:
- Not DEPC-treated: well-suited for applications that may be acutely sensitive to residual DEPC (i.e., oocyte injection)
- Autoclaved, membrane-filtered
- Tested RNase- and DNase-free water
Membrane-filtered and autoclaved water
Non DEPC-treated, nuclease-free water has been autoclaved, specifically for elimination of RNases and DNases. DEPC-treated water is a great option when DEPC presence is irrelevant. However, for some downstream applications, such as oocyte injection or experiments that involve Tris buffer, DEPC treatment is not recommended. Tris contains an amino group which inactivates DEPC, making it unavailable to inactivate RNases.
Nuclease-free water for PCR
Nuclease-free water for PCR should be certified nuclease-free (RNases and DNases), and free of any nucleic acid contamination, such as genomic DNA, that can lead to false RT-PCR signals.
Our nuclease-free water for PCR has the following features:
- RT-PCR-grade water: well-suited for use in any PCR or RT-PCR application
- Each lot tested for nuclease contamination
- Autoclaved, membrane-filtered
- RNase- and DNase-free, genomic DNA-free
Why is nuclease free water used in PCR?
Nuclease-free water is used in PCR to prevent the degradation of nucleic acids and avoid non-specific amplification.
PCR reactions involve small volumes and low concentrations of DNA so even trace amounts of nucleases can significantly impact the integrity of these samples. Using nuclease-free water helps maintain the integrity of the DNA throughout the PCR process.
DNase- and RNase-free water
DNase- and RNase-free water is also known as UltraPure water. UltraPure distilled water is quality tested and no DNase, RNase, or protease activity is detected.
Our UltraPure water has the following features:
- Tested RNase- and DNase-free water, also protease-free
- Autoclaved and 0.1-µm membrane-filtered
- Designed for use in all molecular applications
To meet the special challenges of working with RNA, Thermo Fisher water is certified nuclease-free. They are Type II 18-megohm filtered (via state-of-the-art reverse osmosis filtration and deionization), followed by autoclaving and membrane filtration. The purification equipment used to produce Thermo Fisher waters is subjected to routine maintenance and testing procedures according to rigid ISO 9001 specifications.
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For Research Use Only. Not for use in diagnostic procedures.
For Research Use Only. Not for use in diagnostic procedures.