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Jianshi Biotechnology (Beijing) Co., Ltd.

DNase I (JSR-E-1010-A)

Item number	Product Name	Packaging Specifications	Price
JSR-E-1010-A	DNase I (100 μl)	bottle	Inquiry for price

Keywords

Jianshi Bio DNase I (RNase-free) (Recombinant Deoxyribonuclease I)

Product Overview

This product is recombinant DNase I (RNase‑free), produced by recombinant expression in Escherichia coli. Its key advantages are as follows: ※ Efficient DNA degradation , suitable for RNA purification and pre‑processing prior to RT‑PCR/qPCR; ※ Can generate random cuts or double-strand blunt/short-overhang ends as needed. , flexibly applicable to various experimental settings; ※ Enzyme activity is stable and controllable, with excellent reproducibility. , ensuring the consistency of experimental results; ※ Simple and gentle operation , suitable for use on ice and rapidly inactivated at high temperatures with EDTA; the experimental procedure is simple and safe; ※ High-purity recombinant expression , free from RNase contamination, ensuring RNA integrity; ※ Strict quality control Each batch undergoes activity testing and purity verification. The product catalog number is JSR‑E‑1010‑A and is intended for research use only (RUO); it is not for clinical diagnostic use.

Product Features

※ Efficient DNA degradation : Recombinant DNase I efficiently degrades both single-stranded and double-stranded DNA, making it ideal for the complete removal of genomic DNA from RNA samples and ensuring the accuracy of downstream assays.
※ Enzyme activity is stable and controllable. : The enzyme activity is clearly defined (Kunitz units), exhibits stable activity, and shows minimal batch-to-batch variability, ensuring experimental reproducibility;
※ Easy and safe to operate : The enzyme solution can be rapidly inactivated by incubation at 70°C or by the addition of EDTA, without the need for complex purification steps;
※ High purity, RNase-free : Recombinantly expressed and rigorously purified, with no RNase residues, ensuring RNA samples are protected from degradation;
※ Compatible buffer and diluent : A 10× reaction buffer and a dedicated diluent are provided with the product, enabling convenient and precise preparation of working solutions.
※ Strict quality control system Each batch of product is tested for activity, purity, and RNase residues, with a certificate of analysis provided.
※ Long-term stable preservation Store protected from light at -25°C to -15°C; shelf life up to 1 year. We recommend aliquoting for storage to avoid repeated freeze-thaw cycles.
※ Suitable for a variety of downstream assays. : Widely used for RNA purification, RT‑PCR, qPCR, DNA removal prior to cDNA synthesis, and DNA fragmentation, among other applications;

DNase I (RNase-free) Technical Specifications

Product Information	Specifications/Parameters
Product item number	JSR-E-1010-A
Product ingredients	DNase I (RNase-free) - 10 U/μL (100 μL) DNase I Reaction Buffer (10×) (1 mL) DNase I (RNase-free) Diluent (500 μL)
Definition of Enzyme Activity	1 Kunitz unit: the amount of enzyme required to increase the absorbance at 260 nm of the reaction mixture by 0.001 within 1 minute, using calf thymus DNA as the substrate, under conditions of 25°C and pH 5.0.
Recommended concentration	It is recommended to dilute the 10 U/μL stock solution to 2 U/μL before use.
Storage conditions	Store protected from light at -25 to -15°C; shelf life: 2 years.
Transportation Conditions	Dry ice transportation
Purpose	For Research Use Only (RUO)

Product Basic Information

Item number : JSR‑E‑1010‑A
Source : Recombinant expression in Escherichia coli
Definition of Enzyme Activity : Kunitz unit (25°C, pH 5.0)
Concentration : 10 U/μL (recommended to dilute to 2 U/μL for use)

Storage and Transportation

Storage conditions : Store protected from light at ‑25 ~ ‑15°C
Validity period : 1 year (recommended to aliquot to avoid repeated freeze-thaw cycles)
Mode of transportation Dry ice transportation
Operational Precautions : For use on ice; do not subject to vigorous shaking.

Product Components (Kit)

DNase I (RNase‑free) 10 U/μL : 100 μL
DNase I Reaction Buffer (10×) : 1 mL
DNase I (RNase‑free) Diluent : 500 μL
Purpose : For Research Use Only (RUO)

DNase I (RNase‑free) Frequently Asked Questions

1: What are the main functions and typical application scenarios of this product?

Recombinant DNase I efficiently degrades both single‑stranded and double‑stranded DNA, making it particularly well suited for removing genomic DNA contamination during RNA purification and for pre‑processing in RT‑PCR and qPCR. It can also be used for DNA fragmentation and for generating molecules with specific terminal structures in molecular biology experiments.

• Typical applications: digestion of residual DNA in RNA samples, DNase I footprinting, random DNA fragmentation, and preparation of blunt-ended or sticky-ended DNA fragments.

• Since it contains no RNase, it can be used with confidence in RNA‑related experiments without degrading RNA.

2: How is the enzyme activity unit (Kunitz unit) defined?

1 Kunitz unit is defined as the amount of enzyme required to increase the absorbance at 260 nm by 0.001 per minute, using calf thymus DNA as the substrate under conditions of 25°C and pH 5.0.

• This product is supplied at a concentration of 10 U/μL; prior to use, it is recommended to dilute it with the provided diluent to a working solution of 2 U/μL.

• The activity is clearly defined, facilitating accurate dosage calculations and ensuring experimental reproducibility.

3: How should the product be stored? How long can it be kept after opening?

• Unopened: Store at ‑25 to ‑15°C, protected from light; shelf life: 1 year.

• After opening: It is recommended to aliquot immediately into single-use portions (e.g., 10 μL per tube) and store at ‑25 to ‑15°C, avoiding repeated freeze–thaw cycles. Once aliquoted, the product remains stable until the end of its original shelf life.

• Shipping is conducted using dry ice; upon receipt, please transfer the product to a −20°C freezer immediately.

Important Repeated freeze–thaw cycles can lead to a significant decline in enzyme activity; therefore, always aliquot and store the enzyme.

4: How should DNase I be properly diluted and used?

It is recommended to use the one provided in the kit. DNase I (RNase‑free) Diluent Dilute the stock solution (10 U/μL) to 2 U/μL. For example: pipette 10 μL of the stock solution into 40 μL of diluent, gently invert to mix, and keep on ice for later use.

• Perform all procedures on ice; vortexing or vigorous shaking is prohibited.

• Typical reaction setup: Add 1 μL of DNase I (2 U/μL) to a 1 μg RNA sample and incubate at 37°C for 15–30 minutes.

• The diluted working solution should be used up on the same day and must not be refrozen.

5: Why are divalent metal ions such as Ca²⁺ and Mg²⁺ required? How do they influence the characteristics of enzymatic cleavage?

• DNase I activity is dependent on divalent metal ions. The reaction buffer (10×) already contains optimal concentrations of MgCl₂ and CaCl₂.

• In Mg²⁺ When present, DNase I can randomly cleave double-stranded DNA at any site, generating oligonucleotides with a 5′‑P and a 3′‑OH terminus.

• In Mn²⁺ When present, DNase I cleaves the DNA double strand at the same site, generating blunt ends or sticky ends with 1–2 nucleotide overhangs.

Tip : To obtain a specific end‑type, you can substitute the divalent cation in the buffer (e.g., replace MgCl₂ with MnCl₂).

6: How can DNase I be effectively inactivated to avoid interfering with downstream experiments?

This product offers two convenient inactivation methods: ① Heat inactivation : Incubate at 70°C for 10 minutes; ② EDTA chelation inactivation : Add EDTA to a final concentration of 5 mM and incubate at room temperature for 5 minutes.

• After heat inactivation, it can be used directly for RT‑PCR or qPCR without additional purification.

• EDTA inactivation is suitable for downstream applications that require low-temperature conditions; the inactivated product can be stored on ice for a short period.

• If EDTA is used for inactivation, ensure that the final EDTA concentration in the reaction mixture does not exceed 1 mM to avoid inhibiting the polymerase.

7: Does this product contain RNase contamination? How is RNA integrity ensured?

The product is named “DNase I (RNase‑free)” and has been rigorously quality‑controlled to confirm the absence of RNase residues, ensuring it does not degrade RNA. Each batch undergoes RNase activity testing—using RNA agarose gel electrophoresis—to guarantee that RNA remains intact throughout the digestion process.

• During handling, gloves must still be worn, RNase‑free consumables should be used, and contamination from exogenous RNases—such as saliva or skin—should be avoided.

• The accompanying dilution and buffer solutions have also been treated with DEPC or subjected to RNase inactivation.

8: Do samples treated with DNase I need to be purified before being used for reverse transcription or qPCR?

• In most cases, it is not necessary. Inactivated DNase I and its buffer components do not inhibit reverse transcriptase or Taq polymerase.

• However, if subsequent experiments are highly sensitive to ionic strength and EDTA concentration—such as certain one‑step RT‑qPCR assays—it is recommended to remove proteins and salt ions by column purification or ethanol precipitation.

• For conventional two-step RT‑qPCR, simply use 1–5 μL of the inactivated reaction mixture as the template.

Suggestion When using a new batch for the first time, a negative control (without reverse transcriptase) can be set up to verify that DNA has been thoroughly removed.

9: Can the product be used to generate DNA fragments with specific ends (blunt ends or sticky ends)?

Yes. This can be achieved by altering the divalent cations in the buffer solution:
• Mg²⁺ → Random cleavage generates a mixture of oligonucleotides with 5′‑P and 3′‑OH ends (non-specific termini);
• Mn²⁺ → Cleaves both strands at the same position, generating either blunt ends or sticky ends with 1–2 nucleotide overhangs.

• For blunt ends, a reaction system containing MnCl₂ is recommended (e.g., 50 mM Tris‑HCl, pH 7.5, 10 mM MnCl₂, 100 μg/mL BSA).

• The generated sticky ends can be directly used in ligation reactions (e.g., with T4 DNA ligase).

10: What reagents are included in the product kit? Do I need to purchase any additional materials?

The kit includes:

DNase I (RNase‑free) – 10 U/μL, 100 μL
DNase I Reaction Buffer (10×), 1 mL
DNase I (RNase‑free) Diluent, 500 μL

• Users need only prepare the DNA/RNA sample to be processed, RNase-free water, and PCR tubes or centrifuge tubes.

• If special cleavage under Mn²⁺ conditions is required, you must prepare your own MnCl₂ solution (e.g., 1 M MnCl₂).

• All reagents are for research use only and are not intended for human or clinical diagnostic applications.

Attention : Do not use sample diluents containing strong chelating agents (such as high-concentration EDTA), as they may inhibit enzyme activity.