CN113533477A - Method for determining activity of DNA methyltransferase and application thereof - Google Patents

Method for determining activity of DNA methyltransferase and application thereof Download PDF

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CN113533477A
CN113533477A CN202110931159.5A CN202110931159A CN113533477A CN 113533477 A CN113533477 A CN 113533477A CN 202110931159 A CN202110931159 A CN 202110931159A CN 113533477 A CN113533477 A CN 113533477A
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cdte
cds
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郑峻松
朱全敬
李艳
刘华敏
黄辉
方立超
汪莉娜
邓均
朱垂雨
李承红
刘飞雪
吴春梅
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Third Military Medical University TMMU
Army Medical University
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    • G01N27/3278—Sensing specific biomolecules, e.g. nucleic acid strands, based on an electrode surface reaction involving nanosized elements, e.g. nanogaps or nanoparticles
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
    • G01N27/00—Investigating or analysing materials by the use of electric, electrochemical, or magnetic means
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Abstract

The invention belongs to the technical field of enzyme activity detection, and discloses a method for determining DNA methyltransferase activity and application thereof, wherein the method for determining the DNA methyltransferase activity comprises the following steps: performing RGO-CdS: preparing Mn NPs; preparing a carboxylated CdTe QDs and CdTe @ DNA reticular structure; carrying out gold electrode pretreatment; preparing a PEC biosensor; PEC signal response detection is performed. The preparation method is based on the novel nano composite material RGO-CdS: detecting the activity of M.SssI MTase by a PEC biosensor of a dual signal amplification system with a MnNPs and CdTe @ DNA reticular structure; the prepared biosensor realizes the ultra-sensitive detection of M.SssI MTase, the detection range is from 0.01 to 80U/mL, the method is simple to operate, and complex and expensive instruments or complex signal marks are not needed.

Description

Method for determining activity of DNA methyltransferase and application thereof
Technical Field
The invention belongs to the technical field of enzyme activity detection, and particularly relates to a method for determining DNA methyltransferase activity and application thereof.
Background
Currently, DNA methyltransferases catalyze DNA methylation and play a key role in regulating gene expression and development. Aberrant DNA methyltransferase activity leads to aberrant DNA methylation, which is closely associated with many types of diseases such as cancer. Clearly, DNA methyltransferase activity is considered as a potential cancer biomarker and a target for drug action in cancer therapy. Therefore, the development of a sensitive and selective method for the analysis of DNA methyltransferase activity and the screening of inhibitors thereof (anti-methylation drugs) is of great importance for the early diagnosis and treatment of cancer.
At present, conventional methods for detecting DNA methyltransferase activity include gel electrophoresis, high performance liquid chromatography, and radiolabelling. Although these methods are well established, most of them have the disadvantages of time and labor consuming, cumbersome procedure, low sensitivity, and the need for complicated and expensive instruments or cumbersome signal labeling or the need for radioactive reagents. Therefore, a new method for determining the activity of DNA methyltransferase is needed to overcome the shortcomings of the prior art and to improve the sensitivity of enzyme activity detection.
Through the above analysis, the problems and defects of the prior art are as follows: the traditional method for detecting the activity of the DNA methyltransferase has the defects of time and labor consumption, complex operation of the method, low sensitivity, complex and expensive instruments or complex signal labeling or radioactive reagents and the like.
The difficulty in solving the above problems and defects is: it is necessary to go through a cumbersome pretreatment process and a complicated labeling process, and these steps result in a prolonged detection time and a low sensitivity of detection.
The significance of solving the problems and the defects is as follows: the PEC method not only has high optical sensitivity and high electrochemical stability, but also has the advantages of small background interference, simple and convenient operation, quick detection response and the like. Therefore, under the action of the dual-signal amplification system, by analyzing the relation between the concentration of the M.SssI MTase and the generated photocurrent signal response, the method can sensitively detect the activity of the M.SssI MTase and provide a new idea and a new method for clinical diagnosis of DNA methylation.
Disclosure of Invention
Aiming at the problems in the prior art, the invention provides a method for determining the activity of DNA methyltransferase and application thereof, in particular to a method for determining the activity of DNA methyltransferase based on a double-signal amplification photoelectrochemical method.
The present invention is achieved by a method for measuring a DNA methyltransferase activity, which comprises the steps of:
step one, performing RGO-CdS: preparing Mn NPs;
preparing a carboxylated CdTe QDs and CdTe @ DNA reticular structure;
step three, carrying out gold electrode pretreatment;
preparing a PEC biosensor;
and step five, performing PEC signal response detection.
Further, in step one, the RGO-CdS: preparation of Mn NPs, comprising:
(1) diluting 5mg of graphene oxide with 5mL of ultrapure water, and performing water bath ultrasonic treatment to obtain 1mg/mL of uniformly dispersed liquid;
(2) sequentially adding 0.2g of PVP and 200 mu L of graphene oxide liquid into 50mL of ultrapure water, and continuously stirring by using a glass rod in the process;
(3) 0.0917g of CdCl were sequentially added to the mixed solution2，0.0050g MnCl2·4H2O and 0.1g of TAA are continuously stirred and reacted for 2 hours at the temperature of 80 ℃;
(4) RGO-CdS were obtained by three centrifugation washes at 11000 Xg: mn NPs solid, vacuum drying, and storing the powder in a refrigerator at 4 ℃.
Further, in step two, the preparation of the carboxylated CdTe QDs networks, comprises:
(1) weighing 0.0500g NaBH4And 1.5960g TeO2And reacting NaBH4And TeO2Dissolved in 10mL of ultrapure water to obtain a fresh NaHTe solution;
(2) preparing another mixed solution containing 1mM CdCl2And 1.8mM TGA, and adjusted to pH 11 with 1mM NaOH solution;
(3) introducing N into the mixed solution20.5h to remove O in solution2Then, quickly adding a freshly prepared NaHTe solution to continuously react for 5 hours at 80 ℃, and continuously and mildly stirring the solution;
(4) after the reaction was completed, purified CdTe QDs were obtained by centrifugal washing three times at 11000 Xg, and the CdTe QDs were redispersed in ultrapure water and stored in a refrigerator at 4 ℃.
Further, in the second step, the preparation of the CdTe @ DNA reticular structure comprises the following steps:
(1) preparing 40 mu L of activating solution, wherein the activating solution contains 10mM EDC and 20mM NHS;
(2) adding 40 mu L of Target DNA S31 mu M modified by 5' end amino group into the prepared activation solution for activation for 30 min;
(3) dropwise adding equal volume of CdTe solution into the mixed solution, incubating at 37 ℃ for 2h, and continuously and gently stirring;
(4) after the reaction is finished, the CdTe @ DNA reticular structure is obtained by re-dissolving the CdTe @ DNA reticular structure in ultrapure water through centrifugal washing, and the CdTe @ DNA reticular structure is stored in a refrigerator at the temperature of 4 ℃.
Further, in step three, the gold electrode pretreatment comprises:
(1) polishing the gold electrode with 0.3 μm and 0.05 μm aluminum oxide powder for 5 min;
(2) ultrasonically cleaning the polished gold electrode by acetone, absolute ethyl alcohol and ultrapure water in sequence;
(3) drying the cleaned gold electrode in air, adding a freshly prepared piranha solution, and activating for 15 min;
(4) after the activation, the gold electrode was rinsed with ultrapure water under N2Drying in the atmosphere for later use.
Further, in the third step, the piranha solution is prepared by mixing 30% of hydrogen peroxide and 98% of concentrated sulfuric acid according to the weight ratio of 1: 3, v/v ratio.
Further, in step four, the PEC biosensor is prepared comprising:
(1) take 10 μ L of 3mg/mL RGO-CdS: dripping Mn NPs solution on the surface of the gold electrode; and after complete drying, soaking the electrode in Tris-HCl buffer solution, and reacting for 5 hours at 4 ℃ to obtain RGO-CdS terminated by TGA: Mn/GE, introducing carboxyl on the surface of the electrode to complete the connection of subsequent DNA;
(2) mixing RGO-CdS: soaking the Mn/GE modified electrode into an activation solution to react for 30min so as to activate carboxyl; then, 10 mu L of Probe DNA S11 mu M is dripped on the modified electrode and reacts for 12h at 4 ℃, and DNA chains are captured on the electrode through EDC/NHS coupling reaction;
(3) dropwise adding 1% BSA solution on the modified electrode, and reacting at room temperature for 30min to block the nonspecific site combination; washing with a washing solution for three times, dropwise adding 10 mu L of Target DNA S21 mu M on the surface of the modified electrode, and incubating for 2h at 37 ℃;
(4) the DNA methylation process is completed by dripping 10 mu L of buffer solution on the modified electrode and incubating for 2h at 37 ℃; after washing three times with the washing solution, 10. mu.L of 80U/mL HpaII solution was added dropwise and incubated at 37 ℃ for 2h to negatively unmethylated single-stranded DNA;
(5) dripping 10 mu L of CdTe @ DNA reticular structure on the modified electrode and reacting for 40min at 37 ℃; after the reaction was completed, the prepared electrode was stored in a refrigerator at 4 ℃.
Further, the Tris-HCl buffer consists of 0.1M NaCl and 0.3M TGA; the activating solution consists of 10mM EDC and 20mM NHS; the buffer consists of 160U M SAM and 0-150U/mL M.SssI MTase.
Further, in step five, the PEC signal response detection comprises:
performing photocurrent signal response detection on a photoelectrochemical workstation by using a three-electrode system;
in the system, an Ag/AgCl electrode is used as a reference electrode, a platinum electrode is used as an auxiliary electrode, and a gold electrode with the diameter of 2mm is used as a working electrode; the photocurrent signal response was detected in 0.1M PBS buffer with white light as the detection light source, switching the light detection every 10s while applying a voltage of 0.0V.
Further, the PBS buffer was 0.1M AA, pH 7.4.
Another object of the present invention is to provide a use of the method for measuring DNA methyltransferase activity in the detection of DNA methyltransferase activity.
By combining all the technical schemes, the invention has the advantages and positive effects that: the method for determining the activity of DNA methyltransferase provided by the invention prepares a new nano composite material RGO-CdS: detecting the activity of M.SssI MTase by a PEC biosensor of a dual signal amplification system with a Mn NPs and CdTe @ DNA reticular structure; nanocomposite RGO-CdS: mn NPs can generate stronger photocurrent signal response due to the heterojunction structure; the CdTe @ DNA reticular structure can accelerate electrons to RGO-CdS due to the narrower forbidden bandwidth: the Mn NPs are transferred, thereby generating an extremely strong photocurrent signal response. With the help of a dual signal amplification system, the biosensor prepared by the invention realizes the ultra-sensitive detection of M.SssI MTase, the detection range is from 0.01 to 80U/mL, and compared with methods reported by other documents, the method is simple to operate and does not need complex and expensive instruments or complex signal markers.
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In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings needed to be used in the embodiments of the present invention will be briefly described below, and it is obvious that the drawings described below are only some embodiments of the present invention, and it is obvious for those skilled in the art that other drawings can be obtained according to the drawings without creative efforts.
FIG. 1 is a flowchart of a method for determining DNA methyltransferase activity according to an embodiment of the present invention.
Detailed Description
In order to make the objects, technical solutions and advantages of the present invention more apparent, the present invention is further described in detail with reference to the following embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention.
In view of the problems of the prior art, the present invention provides a method for determining DNA methyltransferase activity and the application thereof, and the present invention is described in detail with reference to the accompanying drawings.
As shown in FIG. 1, the method for determining the activity of DNA methyltransferase provided in the embodiments of the present invention includes the following steps:
s101, performing RGO-CdS: preparing Mn NPs;
s102, preparing a carboxylated CdTe QDs and CdTe @ DNA reticular structure;
s103, carrying out gold electrode pretreatment;
s104, preparing a PEC biosensor;
and S105, detecting the PEC signal response.
The technical solution of the present invention will be further described with reference to the following examples.
1. The process steps for determining the activity of DNA methyltransferase provided by the embodiment of the invention are as follows:
(1) RGO-CdS: preparation of Mn NPs
First, 5mg of graphene oxide was diluted with 5mL of ultrapure water, and a uniformly dispersed liquid was obtained by water bath ultrasonic treatment, the concentration of which was 1 mg/mL. Then, 0.2g of PVP and 200 μ L of the graphene oxide liquid were sequentially added to 50mL of ultrapure water while stirring with a glass rod. Then, 0.09 was added to the mixed solution in order17g CdCl2，0.0050g MnCl2·4H2O and 0.1g of TAA were reacted at 80 ℃ for 2 hours with continuous stirring. Finally, RGO-CdS were obtained by three centrifugation washes of 11000 Xg: mn NPs solid, vacuum drying, and storing the powder in a refrigerator at 4 ℃.
(2) Preparation of carboxylated CdTe QDs and CdTe @ DNA reticular structure
First, 0.0500g of NaBH was weighed4And 1.5960g TeO2They were dissolved in 10mL of ultrapure water to obtain a fresh NaHTe solution. Next, another mixed solution containing 1mM CdCl was prepared2And 1.8mM TGA, and adjusted to pH 11 with 1mM NaOH solution. Introducing N into the mixed solution2For half an hour to remove O in the solution2Then, freshly prepared NaHTe solution was rapidly added and the reaction was continued at 80 ℃ for 5 hours with continuous gentle stirring. After the reaction is finished, purified CdTe QDs are obtained by three centrifugal washes of 11000 Xg, redispersed in ultrapure water and stored in a refrigerator at 4 ℃. The preparation method of the CdTe @ DNA reticular structure comprises the following steps: first, 40. mu.L of an activation solution containing 10mM EDC and 20mM NHS was prepared. Subsequently, 40. mu.L of Target DNA S3 (1. mu.M) modified with an amino group at the 5' -end was added to the prepared activation solution and activated for 30 minutes. Subsequently, an equal volume of CdTe solution was added dropwise to the mixed solution and incubated at 37 ℃ for 2 hours with constant gentle stirring. After the reaction is finished, the CdTe @ DNA reticular structure is obtained by re-dissolving the CdTe @ DNA reticular structure in ultrapure water through centrifugal washing, and the CdTe @ DNA reticular structure is stored in a refrigerator at the temperature of 4 ℃.
(3) Pretreatment of gold electrode
First, the gold electrode was polished for 5 minutes with aluminum oxide powders having a diameter of 0.3 μm and a diameter of 0.05 μm in this order. And then, ultrasonically cleaning the polished gold electrode by acetone, absolute ethyl alcohol and ultrapure water in sequence. Drying the cleaned gold electrode in air, and adding freshly prepared piranha solution [ 30% hydrogen peroxide and 98% concentrated sulfuric acid (1: 3), v/v]Activation was carried out for 15 minutes. After the activation, the gold electrode was rinsed with ultrapure water under N2Drying in the atmosphere for later use.
(4) Preparation of PEC biosensors
First, 10 μ L of RGO-CdS: mn NPs solution (3mg/mL) is dripped on the surface of the gold electrode. After completely drying, in order to introduce carboxyl groups on the electrode surface to complete the subsequent DNA ligation, the electrode was soaked in Tris-HCl buffer (0.1M NaCl, 0.3M TGA) and reacted at 4 ℃ for 5 hours to obtain TGA-terminated RGO-CdS: Mn/GE. Then, RGO-CdS: the Mn/GE modified electrode was immersed in an activation solution (10mM EDC, 20mM NHS) and reacted for 30 minutes to activate the carboxyl group. Next, 10. mu.L of Probe DNA S1 (1. mu.M) was dropped onto the modified electrode and reacted at 4 ℃ for 12 hours, and the DNA strand was captured on the electrode by EDC/NHS coupling reaction. Subsequently, a 1% BSA solution was added dropwise to the modified electrode and reacted at room temperature for 30 minutes to block non-specific site binding. After washing three times with washing solution, 10. mu.L of Target DNA S2 (1. mu.M) was added dropwise to the modified electrode surface and incubated at 37 ℃ for 2 hours. DNA methylation was accomplished by dropping 10. mu.L of buffer (160. mu.M SAM, 0-150U/mL M.SssI MTase) onto the modified electrode and incubating for 2 hours at 37 ℃. After washing three times with the wash solution, 10. mu.L of 80U/mL HpaII solution was added dropwise and incubated at 37 ℃ for 2 hours to inactivate unmethylated single-stranded DNA. Finally, 10. mu.L of CdTe @ DNA network structure was added dropwise to the modified electrode and reacted at 37 ℃ for 40 minutes. After the reaction was completed, the prepared electrode was stored in a refrigerator at 4 ℃.
(5) PEC signal response detection
The experiment uses a three-electrode system to perform photocurrent signal response detection on a photoelectrochemical workstation. In this system, an Ag/AgCl electrode was used as a reference electrode, a platinum electrode as an auxiliary electrode, and a 2mm diameter gold electrode as a working electrode. The photocurrent signal response was detected in 0.1M PBS buffer (0.1M AA, ph7.4) with white light as the detection light source, switching light detection every 10 seconds. While the applied voltage was 0.0V.
2. Results of the experiment
The invention prepares the new nano composite material based on RGO-CdS: the activity of M.SssI MTase was detected by PEC biosensor of dual signal amplification system of Mn NPs and CdTe @ DNA networks. Nanocomposite RGO-CdS: the Mn NPs can generate stronger photocurrent signal response due to the heterojunction structure of the Mn NPs. The CdTe @ DNA reticular structure can accelerate electrons to RGO-CdS due to the narrower forbidden bandwidth: the Mn NPs are transferred, thereby generating an extremely strong photocurrent signal response. With the help of a dual signal amplification system, the prepared biosensor realizes the ultra-sensitive detection of M.SssI MTase, the detection range is from 0.01 to 80U/mL, and compared with methods reported by other documents, the method is simple to operate and does not need complex and expensive instruments or complex signal labeling.
The technical effects of the present invention will be described in detail with reference to experiments.
The experiment constructs a novel PEC biosensor, and detects the activity of M.SssI MTase by using a dual signal amplification strategy of a mesh structure of RGO-CdS, Mn NPs and CdTe @ DNA. First, RGO-CdS: Mn NPs are attached to the surface of a gold electrode as a base material. Subsequently, the probe DNAS1, BSA, and the target DNA S2 having a DNA methylation recognition sequence were captured on the modified electrode in this order. After the methylation and digestion process, the methylated double stranded DNA can remain and hybridize with the CdTe @ DNA network, producing an enhanced photocurrent signal response.
Under the optimal experimental conditions, the photocurrent (I) and the logarithm of the M.SssI MTase concentration have a good linear relation, the linear range is 0.01U/mL to 80U/mL, and the detection limit is 0.0071U/mL.
The above description is only for the purpose of illustrating the present invention and the appended claims are not to be construed as limiting the scope of the invention, which is intended to cover all modifications, equivalents and improvements that are within the spirit and scope of the invention as defined by the appended claims.

Claims (10)

1. A method for measuring a DNA methyltransferase activity, comprising:
RGO-CdS: preparing MnNPs;
preparing a carboxylated CdTe QDs and CdTe @ DNA reticular structure;
pretreating a gold electrode;
preparing a PEC biosensor;
the PEC signal response is detected.
2. The method for determining DNA methyltransferase activity of claim 1 wherein the RGO-CdS: preparation of MnNPs, comprising:
(1) diluting 5mg of graphene oxide with 5mL of ultrapure water, and performing water bath ultrasonic treatment to obtain 1mg/mL of uniformly dispersed liquid;
(2) sequentially adding 0.2g of PVP and 200 mu L of graphene oxide liquid into 50mL of ultrapure water, and continuously stirring by using a glass rod in the process;
(3) 0.0917g of CdCl were sequentially added to the mixed solution2，0.0050g MnCl2·4H2O and 0.1g of TAA, and continuously stirring and reacting for 2 hours at the temperature of 80 ℃;
(4) RGO-CdS were obtained by three centrifugation washes at 11000 Xg: MnNPs solid, vacuum drying, and storing the powder in a refrigerator at 4 ℃.
3. The method for determining the activity of DNA methyltransferase as claimed in claim 1, characterized in that the preparation of the carboxylated CdTe QDs networks comprises:
(1) weighing 0.0500g NaBH4And 1.5960g TeO2And reacting NaBH4And TeO2Dissolved in 10mL of ultrapure water to obtain a fresh NaHTe solution;
(2) preparing another mixed solution containing 1mM CdCl2And 1.8mM TGA, and adjusted to pH 11 with 1mM NaOH solution;
(3) introducing N into the mixed solution20.5h to remove O in solution2Then, quickly adding a freshly prepared NaHTe solution to continuously react for 5 hours at 80 ℃, and continuously and mildly stirring the solution;
(4) after the reaction was completed, purified CdTe QDs were obtained by centrifugal washing three times at 11000 Xg, and the CdTe QDs were redispersed in ultrapure water and stored in a refrigerator at 4 ℃.
4. The method for determining the activity of DNA methyltransferase of claim 1 wherein the preparation of the CdTe @ DNA network comprises:
(1) preparing 40 mu L of activating solution, wherein the activating solution contains 10mM EDC and 20mM NHS;
(2) adding 40 mu L of Target DNA S31 mu M modified by 5' end amino group into the prepared activation solution for activation for 30 min;
(3) dropwise adding equal volume of CdTe solution into the mixed solution, incubating at 37 ℃ for 2h, and continuously and gently stirring;
(4) after the reaction is finished, the CdTe @ DNA reticular structure is obtained by re-dissolving the CdTe @ DNA reticular structure in ultrapure water through centrifugal washing, and the CdTe @ DNA reticular structure is stored in a refrigerator at the temperature of 4 ℃.
5. The method for determining the activity of DNA methyltransferase of claim 1 wherein the gold electrode pretreatment comprises:
(1) polishing the gold electrode with 0.3 μm and 0.05 μm aluminum oxide powder for 5 min;
(2) ultrasonically cleaning the polished gold electrode by acetone, absolute ethyl alcohol and ultrapure water in sequence;
(3) drying the cleaned gold electrode in air, adding a freshly prepared piranha solution, and activating for 15 min;
(4) after the activation, the gold electrode was rinsed with ultrapure water under N2Drying in the atmosphere for later use.
6. The method for measuring DNA methyltransferase activity according to claim 1, wherein the piranha solution is prepared from 30% hydrogen peroxide and 98% concentrated sulfuric acid in a ratio of 1: 3, v/v ratio.
7. The method for determining DNA methyltransferase activity of claim 1, wherein the PEC biosensor is prepared by:
(1) take 10 μ L of 3mg/mL RGO-CdS: dropwise adding MnNPs solution on the surface of the gold electrode; and after complete drying, soaking the electrode in Tris-HCl buffer solution, and reacting for 5 hours at 4 ℃ to obtain RGO-CdS terminated by TGA: Mn/GE, introducing carboxyl on the surface of the electrode to complete the connection of subsequent DNA;
(2) mixing RGO-CdS: soaking the Mn/GE modified electrode into an activation solution to react for 30min so as to activate carboxyl; then, 10 mu L of Probe DNA S11 mu M is dripped on the modified electrode and reacts for 12h at 4 ℃, and DNA chains are captured on the electrode through EDC/NHS coupling reaction;
(3) dropwise adding 1% BSA solution on the modified electrode, and reacting at room temperature for 30min to block the nonspecific site combination; washing with a washing solution for three times, dropwise adding 10 mu L of Target DNA S21 mu M on the surface of the modified electrode, and incubating for 2h at 37 ℃;
(4) the DNA methylation process is completed by dripping 10 mu L of buffer solution on the modified electrode and incubating for 2h at 37 ℃; after washing three times with the washing solution, 10. mu.L of 80U/mL HpaII solution was added dropwise and incubated at 37 ℃ for 2h to negatively unmethylated single-stranded DNA;
(5) dripping 10 mu L of CdTe @ DNA reticular structure on the modified electrode and reacting for 40min at 37 ℃; after the reaction was completed, the prepared electrode was stored in a refrigerator at 4 ℃.
8. The method for measuring DNA methyltransferase activity according to claim 7 wherein the Tris-HCl buffer consists of 0.1M NaCl and 0.3M TGA; the activating solution consists of 10mM EDC and 20mM NHS; the buffer consists of 160U M SAM and 0-150U/mL M.SssIMTase.
9. The method of determining DNA methyltransferase activity of claim 1 wherein the PEC signal is responsive to a test comprising:
performing photocurrent signal response detection on a photoelectrochemical workstation by using a three-electrode system;
in the system, an Ag/AgCl electrode is used as a reference electrode, a platinum electrode is used as an auxiliary electrode, and a gold electrode with the diameter of 2mm is used as a working electrode; detecting photocurrent signal response in 0.1M PBS buffer solution, wherein white light is used as a detection light source, switching on and off the light detection every 10s, and simultaneously applying a voltage of 0.0V;
the PBS buffer was 0.1M AA, pH 7.4.
10. Use of the method for detecting DNA methyltransferase activity according to any of claims 1 to 9 in the detection of DNA methyltransferase activity.
CN202110931159.5A 2021-08-13 2021-08-13 Method for determining activity of DNA methyltransferase and application thereof Pending CN113533477A (en)

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Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN105675687A (en) * 2016-03-23 2016-06-15 安徽师范大学 Method for preparing electrochemical biosensors and method for detecting activity of DNA (deoxyribonucleic acid) methyl transferase
CN110702910A (en) * 2019-08-27 2020-01-17 东南大学 Photoelectrochemical immunosensor for detecting activity of DNA methylase and preparation method and application thereof

Patent Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN105675687A (en) * 2016-03-23 2016-06-15 安徽师范大学 Method for preparing electrochemical biosensors and method for detecting activity of DNA (deoxyribonucleic acid) methyl transferase
CN110702910A (en) * 2019-08-27 2020-01-17 东南大学 Photoelectrochemical immunosensor for detecting activity of DNA methylase and preparation method and application thereof

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
JING LUO 等: "Dual-signal amplified photoelectrochemical assay for DNA methyltransferase activity based on RGO-CdS:Mn nanoparticles and a CdTe@DNA network", 《SENSORS AND ACTUATORS B: CHEMICAL》, pages 1 - 8 *

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