CN108949528B - Multi-element volume column chip for visually detecting copper, lead and mercury ions and detection method thereof - Google Patents
Multi-element volume column chip for visually detecting copper, lead and mercury ions and detection method thereof Download PDFInfo
- Publication number
- CN108949528B CN108949528B CN201810315527.1A CN201810315527A CN108949528B CN 108949528 B CN108949528 B CN 108949528B CN 201810315527 A CN201810315527 A CN 201810315527A CN 108949528 B CN108949528 B CN 108949528B
- Authority
- CN
- China
- Prior art keywords
- detecting
- ions
- ink
- chip
- sample
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Active
Links
Images
Classifications
-
- C—CHEMISTRY; METALLURGY
- C12—BIOCHEMISTRY; BEER; SPIRITS; WINE; VINEGAR; MICROBIOLOGY; ENZYMOLOGY; MUTATION OR GENETIC ENGINEERING
- C12Q—MEASURING OR TESTING PROCESSES INVOLVING ENZYMES, NUCLEIC ACIDS OR MICROORGANISMS; COMPOSITIONS OR TEST PAPERS THEREFOR; PROCESSES OF PREPARING SUCH COMPOSITIONS; CONDITION-RESPONSIVE CONTROL IN MICROBIOLOGICAL OR ENZYMOLOGICAL PROCESSES
- C12Q1/00—Measuring or testing processes involving enzymes, nucleic acids or microorganisms; Compositions therefor; Processes of preparing such compositions
- C12Q1/68—Measuring or testing processes involving enzymes, nucleic acids or microorganisms; Compositions therefor; Processes of preparing such compositions involving nucleic acids
- C12Q1/6813—Hybridisation assays
- C12Q1/6816—Hybridisation assays characterised by the detection means
- C12Q1/6825—Nucleic acid detection involving sensors
Landscapes
- Chemical & Material Sciences (AREA)
- Life Sciences & Earth Sciences (AREA)
- Organic Chemistry (AREA)
- Analytical Chemistry (AREA)
- Zoology (AREA)
- Wood Science & Technology (AREA)
- Proteomics, Peptides & Aminoacids (AREA)
- Health & Medical Sciences (AREA)
- Engineering & Computer Science (AREA)
- Microbiology (AREA)
- Immunology (AREA)
- Molecular Biology (AREA)
- Biotechnology (AREA)
- Biophysics (AREA)
- Physics & Mathematics (AREA)
- Biochemistry (AREA)
- Bioinformatics & Cheminformatics (AREA)
- General Engineering & Computer Science (AREA)
- General Health & Medical Sciences (AREA)
- Genetics & Genomics (AREA)
- Measuring Or Testing Involving Enzymes Or Micro-Organisms (AREA)
- Investigating Or Analyzing Non-Biological Materials By The Use Of Chemical Means (AREA)
Abstract
The invention discloses a multi-element volume column chip for visually detecting copper, lead and mercury ions, which comprises a first glass chip and a second glass chip, wherein an ink moving channel group, an ink indicating channel and a sample groove group are arranged on the inner side of the first glass chip, and a reagent groove group is arranged on the inner side of the second glass chip; the multi-element volume column chip is used for pushing the ink column to move by oxygen generated by hydrogen peroxide decomposition, a detection result is displayed on the chip, the concentration of copper, lead and mercury ions in water can be visually and quantitatively detected without expensive instruments and complex data processing processes, the result is accurate, the operation is simple, the cost is low, and the application range is wide.
Description
Technical Field
The invention belongs to the technical field of microfluidic analysis, and particularly relates to a multi-element volume column chip for visually detecting copper ions, lead ions and mercury ions and a detection method thereof.
Background
At present, the detection of metal ions in water is mainly based on atomic absorption, atomic emission spectroscopy and inductively coupled plasma mass spectrometry, and the instruments can detect various metal ions simultaneously, and have high detection sensitivity and low detection limit. However, the instruments are expensive and have high technical requirements on operators, which limits the application of field detection and resource-poor areas.
To simplify the operation and reduce the cost, a DNA visualization detection method based on metal-specific response is designed for the detection of metal ions. A series of specific DNAs aiming at metal ions can be generated by in vitro screening and are used for detecting various metal ions. The metal ion sensor based on DNA molecule design has the characteristics that: the DNA molecule can be repeatedly deformed and renatured without losing activity. And secondly, the DNA molecules are easy to modify and mark, so that the metal ion sensor is more reasonably designed. The DNA can be obtained by chemical synthesis, and the cost is low. However, these DNA-based visual tests often only give qualitative or semi-quantitative test results, and the detection limit of the method cannot meet the national standard, and an instrumental method is still required. And the number of the metal ions detected by the methods is too small, so that the practical application is limited. Therefore, the invention of a method for visual quantitative detection of various metal ions is of practical significance.
Disclosure of Invention
In order to solve the problems in the prior art, the invention provides the multi-element volume column chip for visually detecting the copper ions, the lead ions and the mercury ions and the detection method thereof.
The technical problem to be solved by the invention is realized by the following technical scheme:
a multi-element volume column chip for visually detecting copper, lead and mercury ions comprises a first glass chip and a second glass chip, wherein the first glass chip and the second glass chip are rectangular and have the same size, the inner side of the first glass chip is attached to the inner side of the second glass chip and is in sliding contact with the inner side of the second glass chip, an ink moving channel group, an ink indicating channel and a sample cell group are arranged on the inner side of the first glass chip, the ink moving channel group is positioned on the upper portion of the first glass chip and comprises a first ink moving channel, a second ink moving channel and a third ink moving channel, the first ink moving channel, the second ink moving channel and the third ink moving channel are sequentially arranged in parallel from the left side to the right side of the first glass chip, the sample cell group is positioned on the lower portion of the first glass chip and comprises a first sample cell, a second sample cell and a third sample cell, the first sample groove is positioned below the first ink moving channel, the second sample groove is positioned below the second ink moving channel, the third sample groove is positioned below the third ink moving channel, the ink indicating channel is positioned between the ink moving channel group and the sample groove group and is parallel to the upper edge and the lower edge of the first glass chip, the inner side of the second glass chip is provided with a reagent groove group, the reagent groove group comprises a first reagent groove, a second reagent groove and a third reagent groove, when the first glass chip and the second glass chip are completely overlapped, the sample groove group and the reagent groove group have no overlapped part, when the first glass chip and the second glass chip are partially overlapped with the upper edge and the lower edge aligned, and the first sample groove and the first reagent groove are overlapped, the second sample groove and the second reagent groove, the third sample groove and the third reagent groove are also overlapped, the ink moving channel group, the ink indicating channel and the reagent groove group are communicated, the ink indicating channel is provided with an ink water inlet hole and an ink water outlet hole, the first sample groove, the second sample groove and the third sample groove are respectively provided with a sample injection hole and a sample outflow hole, the first reagent groove, the second reagent groove and the third reagent groove are respectively provided with a reagent injection hole and a reagent outflow hole, the ink water inlet hole, the ink water outlet hole, the sample injection hole, the sample outflow hole, the reagent injection hole and the reagent outflow hole are all located on the first glass chip, and the water column ink indicating channel is filled with ink.
As a further improved technical scheme, the first ink moving channel is used for quantitatively detecting copper ions, the second ink moving channel is used for quantitatively detecting lead ions, the third ink moving channel is used for quantitatively detecting mercury ions, the first ink moving channel, the second ink moving channel and the third ink moving channel are all in a continuous 'S' shape and are parallel to the left side and the right side of the first glass chip, the first glass chip is further provided with an ink moving distance scale, and the ink moving distance scale is positioned at the upper end and the left side and the right side of the ink moving channel group.
As a further improved technical scheme, the first glass chip and the second glass chip are prepared by standard photoetching and wet etching, the inner sides of the first glass chip and the second glass chip are subjected to hydrophobization treatment, and the inner side of the first glass chip and the inner side of the second glass chip are attached through dimethyl silicone oil.
As a further improved technical scheme, the photoresist adopted by the standard photoetching is SPR220-7, the developing solution is AZ400K, and the etching solution adopted by the wet etching is HF and NH4F and HNO3Mixed solution of HF and NH4F and HNO3The molar ratio of (1: 0.5: 0.75), and the hydrophobic agent used for the hydrophobic treatment is perfluorooctyl trichlorosilane.
A detection method of a multi-element volume column chip for visually detecting copper, lead and mercury ions comprises the following steps:
s1, preparing a multi-element volume column chip: taking the multi-element volume column chip for visually and quantitatively detecting the copper, lead and mercury heavy metal ions in the water as claimed in claim 1 or 2;
s2, preparing a magnetic silica nanoprobe modified by nucleic acid: respectively preparing a nucleic acid modified magnetic silica nanoprobe for detecting copper ions, a nucleic acid modified magnetic silica nanoprobe for detecting lead ions and a nucleic acid modified magnetic silica nanoprobe for detecting mercury ions;
s3, preparing a DNA modified platinum nano probe: reducing chloroplatinic acid by ascorbic acid to prepare platinum nanoparticles, and covalently bonding DNA modified by sulfydryl and used for detecting copper ions, DNA used for detecting lead ions and DNA used for detecting mercury ions to the surfaces of the platinum nanoparticles respectively to obtain a DNA modified platinum nanoprobe used for detecting copper ions, a DNA modified platinum nanoprobe used for detecting lead ions and a DNA modified platinum nanoprobe used for detecting mercury ions;
s4, preparing a composite probe solution: incubating the nucleic acid-modified magnetic silica nanoprobe for detecting copper ions in the step S2 with the DNA-modified platinum nanoprobe for detecting copper ions in the step S3 to form a composite probe for detecting copper ions by DNA double strand complementation, then dispersing the composite probe for detecting copper ions in a buffer solution to prepare a composite probe solution for detecting copper ions, incubating the nucleic acid-modified magnetic silica nanoprobe for detecting lead ions in the step S2 with the DNA-modified platinum nanoprobe for detecting lead ions in the step S3 to form a composite probe for detecting lead ions by DNA double strand complementation, then dispersing the composite probe for detecting lead ions in a buffer solution to prepare a composite probe solution for detecting lead ions, and then dispersing the nucleic acid-modified magnetic silica nanoprobe for detecting mercury ions in the step S2 with the DNA-modified platinum nanoprobe for detecting mercury ions in the step S3 Incubating a DNA-modified platinum nano probe for detecting mercury ions, forming a composite probe for detecting mercury ions through DNA double-strand complementation, and then dispersing the composite probe for detecting mercury ions in a buffer solution to prepare a composite probe solution for detecting mercury ions;
s5, establishing a standard curve: adding copper, lead and mercury analytes with different concentrations into the composite probe solution for detecting copper ions, the composite probe solution for detecting lead ions and the composite probe solution for detecting mercury ions in the step S4 respectively to perform light-shielding oscillation reaction, then performing magnet separation to obtain to-be-detected clear liquids of the copper, lead and mercury analytes with different concentrations, taking the to-be-detected clear liquids to add into the first sample cell, the second sample cell and the third sample cell of the multi-element volume column chip in the step S1 respectively, and adding H into the reagent cell group2O2Solution, in the clear liquid to be tested for copper ion, the clear liquid to be tested for lead ion, the clear liquid to be tested for mercury ion and H2O2After the solutions are mixed, recording the advancing distance of the ink column in the multi-element volume column chip, fitting a standard curve equation, and establishing a standard curve;
s6, sample detection: collecting a sample to be detected, filtering to obtain a water sample to be detected, adding the water sample to be detected into the composite probe solution for detecting copper ions, the composite probe solution for detecting lead ions and the composite probe solution for detecting mercury ions in the step S4 respectively to perform light-shielding oscillation reaction, then performing magnet separation to obtain a clear liquid to be detected, adding the clear liquid into the sample tank of the multi-volume column chip in the step S1, and adding H into the reagent tank2O2A solution, wherein the ink column indicating channel of the multi-element volume column chip is filled with ink, and the clear liquid to be detected and the H2O2And (4) after the solutions are mixed, recording the advancing distance of the ink column in the multi-element volume column chip, and finally analyzing by using the standard curve in the step S5 to obtain the concentrations of the copper, lead and mercury heavy metal ions in the water sample to be detected.
As a further improved technical solution, the step S2 specifically includes the following steps:
(a) magnetic Fe prepared by coprecipitation method3O4Nanoparticles;
(b) using magnetic Fe in step (a) by reverse microemulsion method3O4Preparing magnetic silicon dioxide nanoparticles from the nanoparticles;
(c) and respectively covalently bonding amino-modified nucleic acid for detecting copper ions, lead ions and mercury ions to the surface of the magnetic silica nanoparticles by using Schiff base reaction and glutaraldehyde as a cross-linking agent to obtain nucleic acid-modified magnetic silica nanoprobes for detecting copper ions, lead ions and mercury ions.
As a further improved technical scheme, the molar ratio of the TECP and the DNA adopted when the DNA is subjected to thiol modification in the step S3 is 5: 1; the sequence of the sulfhydryl modified DNA for detecting copper ions is SH- (CH)2)65'-GGTAAGCCTGGGCCTCTTTCTTTTTAAGAAAGAAC-3', the sequence of the sulfhydryl modified DNA for detecting lead ions is SH- (CH)2)6-5' -TGAGTGATAAAGCTGGCCGAGCCTCTTCTCTAC-3, wherein the sequence of the sulfhydryl modified DNA for detecting mercury ions is SH- (CH)2)6-5'-ACAAACATGA-3'。
As a further improved technical scheme, the buffer solution in the step S4 is 150mM NaNO3The pH value of the Tris-acetic acid is 8.2, the reaction temperature is 20-25 ℃, and the reaction time is 4 hours.
As a further improved techniqueIn the scheme, the light-shielding oscillation reaction time in the steps S5 and S6 is 30min, and the multi-element volume column chip is slid to enable the clear liquid to be detected and H to be detected2O2Mixing the solution, and mixing the clear solution to be tested with H2O2After the solution is mixed, the solution is waited for 10min, and the detection result is recorded.
The components of the inverse microemulsion system in the step S2 comprise 4.42g of Triton X-100, 18.8mL of cyclohexane and 4mL of hexanol, the buffer solution adopted in the process of activating amino-modified magnetic silica nanoparticles by glutaraldehyde is a PB buffer solution with the pH value of 7.4, the reaction time is 24h, and the amino-modified nucleic acid sequence for detecting copper ions is NH2-(CH2)65'-AAAAAAAAAGCTTCTTTCTAATACGGCTTACC-3', the amino modified nucleic acid sequence for detecting lead ions is NH2-(CH2)6-5 '-AAAAAAAGTAGAGAGGRATCATCACTCA-3', amino modified nucleic acid sequence for detecting mercury ions is NH2-(CH2)65'-TCATGTTTGTTTGTTGGCCCCCCTTCTTTCTTA-3', the amino modified nucleic acids are all used in an amount of 1 mu mol, and the buffer solution adopted in the reaction process of covalently binding the amino modified nucleic acids to the surface of the magnetic NaNO-silica particles is 150mM NaNO325mM Tris-acetate buffer solution with pH 8.2, at the reaction temperature of 20 ℃ for 12 hours.
The invention has the beneficial effects that:
the invention combines a sliding chip, a nanotechnology and a biotechnology, utilizes the specificity recognition principle of DNA to metal ions, dissociates magnetic nanoparticles modified by nucleic acid and platinum nanoparticles to assemble a composite probe in the presence of specific metal ions, and the dissociated platinum nanoprobe is contacted with oxygen generated by hydrogen peroxide to push an ink column to move through the sliding chip.
(1) The multi-element volume column chip has quantitative detection and higher flux, and is suitable for parallel analysis of various metal ions. Three-channel manifoldThe volume column chip can be used for simultaneously detecting copper, lead and mercury metal ions in water samples of an on-site environment, and can also be used for simultaneously detecting the content of the metal ions in three water samples, the detection time is only 10min, and compared with semi-quantitative visual detection in the prior art, the detection limit of the invention is as follows: 1.0nM of copper, 1.0nM of lead and 1.8nM of mercury, which are lower than the detection standards of copper, lead and mercury in drinking water in national standard, high precision, wide test range, and investigation of common Ca2+、Mn2+、Cd2+、Mg2+、Co2+、Ni2+And Zn2+None of the 7 metal ions affected the selectivity of the process.
(2) The chip required by the invention is prepared by two pieces of common glass, the dosage of samples and reagents is less, the detection cost is low, the chip can be used for low-cost quantitative detection, the multi-volume column chip is simple and convenient to operate and can be repeatedly used, and meanwhile, the chip can be combined with a mobile phone intelligent terminal to feed back the analysis result to a monitoring department at the first time.
(3) By replacing other DNA with specific response to metal, the preparation method of the composite probe and the multi-element volume column chip are utilized, the chip flux is designed as required, and the method can be popularized to the visual quantitative detection of more metal ions.
(4) The invention provides a new analysis means for heavy metal detection in environment, food safety, medical treatment and judicial identification.
Drawings
FIG. 1 is a schematic view of a first glass chip and a second glass chip of a multi-element volume column chip according to the present invention when they are fully aligned;
FIG. 2 is a schematic view of the structure of a multi-element volume column chip according to the present invention in which a sample well group and a reagent well group are aligned;
FIG. 3 is a multi-element volume pillar chip mask pattern and chip pattern of the present invention;
FIG. 4 is a view showing the detection of a real sample of the multi-element volume column chip of the present invention.
Description of reference numerals: 1. a first glass chip; 2. a second glass chip; 3. an ink indicating channel; 4. a first ink moving passage; 5. a second ink moving passage; 6. a third ink moving passage; 7. a first sample tank; 8. a second sample cell; 9. a third sample cell; 10. a first reagent tank; 11. a second reagent tank; 12. a third reagent tank; 13. an ink inlet hole; 14. an ink water outlet hole; 15. a sample injection hole; 16. a sample outflow hole; 17. a reagent injection hole; 18. a reagent outflow hole; 19. the ink moves the distance scale.
Detailed Description
The present invention is further illustrated by the following specific examples, which are intended to be illustrative, not limiting and are not intended to limit the scope of the invention.
Examples
As shown in fig. 1-3, a multi-element volume column chip for visually detecting copper, lead and mercury ions comprises a first glass chip 1 and a second glass chip 2, wherein the first glass chip 1 and the second glass chip 2 are rectangular and have the same size, the inner side of the first glass chip 1 is attached to the inner side of the second glass chip 2 and is in sliding contact with the inner side of the second glass chip 2, an ink moving channel group, an ink indicating channel 3 and a sample cell group are arranged on the inner side of the first glass chip 1, the ink moving channel group is arranged on the upper portion of the first glass chip 1 and comprises a first ink moving channel 4, a second ink moving channel 5 and a third ink moving channel 6, the first ink moving channel 4, the second ink moving channel 5 and the third ink moving channel 6 are arranged in parallel from the left side to the right side of the first glass chip 1, the sample cell group is arranged on the lower portion of the first glass chip 1, comprises a first sample groove 7, a second sample groove 8 and a third sample groove 9, wherein the first sample groove 7 is positioned below a first ink moving channel 4, the second sample groove 8 is positioned below a second ink moving channel 5, the third sample groove 9 is positioned below a third ink moving channel 6, an ink indicating channel 3 is positioned between an ink moving channel group and a sample groove group and is parallel to the upper side and the lower side of a first glass chip 1, a reagent groove group is arranged at the inner side of a second glass chip 2 and comprises a first reagent groove 10, a second reagent groove 11 and a third reagent groove 12, when the first glass chip 1 and the second glass chip 2 are completely overlapped, the sample groove group and the reagent groove group have no overlapped part, when the first glass chip 1 and the second glass chip 2 are aligned with each other and are partially overlapped, and when the first sample groove 7 and the first reagent groove 10 are overlapped, the second sample tank 8, the second reagent tank 11, the third sample tank 9 and the third reagent tank 12 are also overlapped, the ink moving channel group, the ink indicating channel 3 and the sample tank group are communicated, the ink indicating channel 3 is provided with an ink water inlet hole 13 and an ink water outlet hole 14, the first sample tank 7, the second sample tank 8 and the third sample tank 9 are provided with a sample injection hole 15 and a sample outflow hole 16, the first reagent tank 10, the second reagent tank 11 and the third reagent tank 12 are provided with a reagent injection hole 17 and a reagent outflow hole 18, the ink water inlet hole 13, the ink water outlet hole 14, the sample injection hole 15, the sample outflow hole 16, the reagent injection hole 17 and the reagent outflow hole 18 are all located on the first glass chip 1, and the ink indicating channel 3 is filled with ink.
In this embodiment, the first ink moving channel 4 is used for quantitatively measuring copper ions, the second ink moving channel 5 is used for quantitatively testing lead ions, the third ink moving channel 6 is used for quantitatively measuring mercury ions, the first ink moving channel 4, the second ink moving channel 5 and the third ink moving channel 6 are all in a continuous S shape and are parallel to the left side and the right side of the first glass chip 1, the first glass chip 1 is further provided with an ink moving distance scale 19, and the ink moving distance scale 19 is located at the upper end and the left side and the right side of the ink moving channel group.
In this embodiment, the first glass chip 1 and the second glass chip 2 are prepared by standard photolithography and wet etching, the inner sides of the first glass chip 1 and the second glass chip 2 are subjected to hydrophobization, and the inner side of the first glass chip 1 and the inner side of the second glass chip 2 are bonded by using dimethicone.
In this embodiment, the photoresist used in the standard lithography is SPR220-7, the developing solution is AZ400K, and the etching solution used in the wet etching is HF or NH4F and HNO3Mixed solution of HF and NH4F and HNO3Is 1:0.5:0.75, and perfluorooctyl is used as a hydrophobizing agent for the hydrophobizing treatmentA radical trichlorosilane.
A detection method of a multi-element volume column chip for visually detecting copper, lead and mercury ions comprises the following steps:
s1, preparing a multi-element volume column chip: taking the multi-element volume column chip for visually and quantitatively detecting three heavy metal ions, namely copper, lead and mercury in water;
s2, preparing the magnetic silica nanoprobe modified by nucleic acid, which comprises the following steps in sequence:
(a) preparation of magnetic Fe3O4The nano particles specifically comprise the following steps in sequence:
(a1) weigh 5.2g of FeCl3And 2.0g of FeCl2Dissolving into 25mL of deoxygenated water together;
(a2) preparing 250mL of 1.5M NaOH solution;
(a3) dropwise adding the solution step into the deoxygenated water of step (a1) under magnetic stirring to produce black Fe3O4After precipitation, Fe was added with a magnet3O4Sucking, removing clear liquid, and cleaning the precipitate with deoxygenated water for 3 times;
(a4) 500mL of 0.01M HCl solution was prepared and added to the Fe in step (a3)3O4In the precipitation, continuously stirring to neutralize residual NaOH;
(a5) washing the precipitate obtained in the step (a4) with deionized water twice for several times to obtain magnetic Fe3O4Colloidal nanoparticles.
(b) The method for synthesizing the magnetic silica nanoparticles specifically comprises the following steps in sequence:
(b1) 4.42g of Triton X-100, 18.8mL of cyclohexane and 4mL of n-hexanol are put into a 50mL conical flask and stirred for 10min, and the solution is uniformly mixed;
(b2) 1mL of highly purified water and 12.5mg of Fe prepared in step (b1) were added3O4Carrying out ultrasonic dispersion on the nano particles;
(b3) dispersing the Fe dispersed in the step (b2)3O4Rapidly adding the nanoparticles to the solution of step (b 1);
(b4) adding 300 μ L of ethyl orthosilicate to the solution obtained at the end of step (b3), and stirring for 40 min;
(b5) adding 200 mu L of ammonia water into the solution obtained at the end of the step (b4) to react for 18 h;
(b6) adding 100 mu L of 3-aminopropyltriethoxysilane into the solution obtained at the end of the step (b5), and continuing to react for 10 h;
(b7) separating the precipitate from the solution obtained in step (b6) with a magnet, washing with 20mL of absolute ethanol for several times, and washing with 20mL of deionized water for several times to obtain magnetic silica nanoparticles
(c) The preparation method of the magnetic silicon dioxide nanoprobe comprises the following steps in sequence:
(c1) ultrasonically dispersing the magnetic silica nanoparticles prepared in example 3 in 20mL of 25mM PB buffer solution with the pH value of 7.4 for 30 min;
(c2) adding 1mL of 50% glutaraldehyde into the solution obtained in the step (c1), and stirring and reacting at 20 ℃ for 24h to obtain aldehyde group activated magnetic silica nanoparticles;
(c3) separating aldehyde group-activated magnetic silica nanoparticles with a magnet, using a magnetic column containing 150mM NaNO3Washing with 25mM Tris-acetate buffer solution (pH 8.2) for several times, and dispersing in 10mL of the Tris-acetate buffer solution;
(c4) taking 0.1mL of the nano solution finally obtained in the step (c3), and adding amino-modified nucleic acid for detecting copper ions, amino-modified nucleic acid for detecting lead ions and amino-modified nucleic acid for detecting mercury ions during preparation aiming at detection of copper, lead and mercury, wherein the nucleic acids are covalently bonded to the surfaces of the magnetic silica nanoparticles by Schiff base reaction, and the adding amounts of different aminated nucleic acids are respectively as follows: 1 μ M nucleic acid for detecting copper ions, 1 μ M nucleic acid for detecting lead ions, 1 μ M nucleic acid for detecting mercury ions, and 4mL nucleic acid containing 150mM NaNO3After reaction for 12 hours, the magnetic silica nanoprobe modified with nucleic acid was separated with a magnet, the free nucleic acid was washed away with the buffer solution, and the Tris-acetate buffer solution was dispersed and stored at 4 ℃ in the dark.
S3, preparing the DNA modified platinum nano probe, and specifically sequentially comprising the following steps:
(d1) taking 500 mu L of 100mM chloroplatinic acid solution, adding 45mL ultrapure water, heating at 80 ℃ for 40min, quickly adding 9mL 0.2M ascorbic acid, continuously heating at 85 ℃ for 30min, centrifugally cleaning with ultrapure water for several times at 5000rpm for 5min to obtain 1mg/mL platinum nanoparticle aqueous solution, and storing in a dark place at 4 ℃;
(d2) thiolated DNA disulfide bond reduction: TCEP is prepared at present, aiming at different systems of copper, lead and mercury, DNA modified by sulfydryl and used for detecting copper ions, DNA modified by sulfydryl and used for detecting lead ions and DNA modified by sulfydryl and used for detecting mercury ions are added during reduction, and the adding amounts are respectively as follows: 10 mu M of DNA for detecting copper ions, 1 mu M of DNA for detecting lead ions, 1 mu M of DNA for detecting mercury ions, and the molar ratio TCEP 5:1, adding TCEP solution with different amounts, adding 10mM acetic acid buffer solution with pH 5.5, and reacting for 1h at room temperature in a dark place;
(d3) heating the platinum nanoparticles prepared in the step (d1) at 85 ℃ for 10min, then taking 0.1mL of platinum nanoparticle solution, adding 4mL of ultrapure water, adding the DNA reduced in the step (d2) into different systems of copper, lead and mercury, reacting for 10h at 4 ℃, centrifuging for 5min at 5000rpm, repeatedly cleaning the platinum nanoprobe modified by the DNA for several times, configuring the platinum nanoprobe in the ultrapure water, and storing the platinum nanoprobe in a dark place at 4 ℃.
S4, preparing a composite probe solution, and specifically sequentially comprising the following steps:
adding 0.1mL of prepared nucleic acid-modified magnetic silica nanoprobe into 30 μ L of DNA-modified platinum nanoprobe solution, and adding 4mL of solution containing 150mM NaNO325mM Tris-acetate buffer pH 8.2. After incubation for 4h in a shaker at room temperature, the composite probe was separated with a magnet, washed with buffer solution several times, and the prepared composite probe was dispersed in 30. mu.L of the above buffer solution and stored at 4 ℃ in the dark.
S5, the actual sample detection method specifically comprises the following steps in sequence:
(e1) a standard curve was established by adding different concentrations of the components to 30. mu.L of the composite probe solution prepared in said step S4And separating out, and shaking on a mixing instrument for 30min in the dark. After magnetic separation, a pipette takes 2 μ L of clear solution, adds the clear solution into a sample tank of the chip, and adds 2 μ L of 30% H into a reagent tank2O2And (3) solution. The chip ink water column indicates that the channel is filled with ink. Sliding the chip to bring the sample into contact with H2O2The solutions were mixed. Recording the advancing distance of the ink column after 10min, wherein the concentration of the analyte and the advancing distance of the ink column form a certain curve relationship, and fitting a standard curve equation by utilizing origin software;
(e2) a river water sample is collected and filtered by a 20-micron membrane. Adding 20 mu L of water sample, adding the mixture into the composite probe solution, and shaking the mixture on a mixing instrument for 30min in the dark. Following the procedure of step (e1), the advancing distance of the ink column was recorded after 10min and the concentration of the analyte was obtained on the standard curve.
As shown in fig. 1-3, a multi-element volume column chip for visually and quantitatively detecting three heavy metal ions of copper, lead and mercury in water is prepared by the following steps:
(1) as shown in fig. 3(a) and 3(b), upper and lower masks for drawing a glass chip are designed and drawn by AutoCAD;
(2) the size of a single glass chip is 75mm multiplied by 50mm multiplied by 1.5mm, the glass chip is cleaned by isopropanol and deionized water, and the glass chip is dried by nitrogen;
(3) treating the surface of the glass sheet for 3min by oxygen plasma;
(4) placing the glass sheet into a glass storage box, taking 1mL of 1, 1, 1, 3, 3, 3-hexamethyldisilazane into a small beaker, placing the glass sheet and the glass sheet in a closed box, standing for 30min, and bonding a volatile reagent to the surface of the glass chip;
(5) placing a glass chip decorated with 1mL of 1, 1, 1, 3, 3, 3-hexamethyldisilazane on a spin coater, spin-coating a photoresist SPR220-7 under a dark condition, rotating at a low speed of 300rpm/min for 5 s; rotating at high speed of 1000rpm/min for 40 s;
(6) placing the glass sheet which is coated with the photoresist in a spin mode on a heating table, drying the photoresist for 3min at 70 ℃, then raising the temperature to 100 ℃, continuing to dry for 8min, and naturally cooling to room temperature;
(7) covering the mask on the glass sheet after being dried with adhesive tape, fixing the four corners with adhesive tape, and removing the mask after exposing the glass sheet on a photoetching machine for 100s by an ultraviolet lamp.
(8) Pouring the AZ400K developing solution into a crystallizing dish, putting the exposed glass sheet into the developing solution, and shaking the developing solution continuously to develop the exposed area of the chip gradually;
(9) wrapping the edges and back of the glass sheet with transparent adhesive tape, placing the chip in HF, NH4F and HNO3In the mixed solution, HF, NH4F and HNO3The molar ratio of the metal oxide to the metal oxide is 1:0.5:0.75, and the hydrophobic reagent adopted in the hydrophobic treatment is perfluorooctyl trichlorosilane, and is etched for 40min at room temperature;
(10) after etching, cleaning the residual etching solution on the surface by using deionized water, sequentially cleaning the residual photoresist by using acetone, isopropanol and deionized water, and drying by using nitrogen;
(11) the first glass chip 1 is fixed to the glass chip substrate with adhesive, and the positions of the ink inlet hole 13, the ink outlet hole 14, the sample inlet hole 15, the sample outlet hole 16, the reagent inlet hole 17, and the reagent outlet hole 18 in the chip are punched with a punch. After punching, adding acetone for ultrasonic treatment, washing off the glue, and taking out the punched chip;
(12) and then, the small engraving and milling machine is used for punching an ink inlet hole 13, an ink outlet hole 14, a sample injection hole 15, a sample outflow hole 16, a reagent injection hole 17 and a reagent outflow hole 18 of the first glass chip 1. After beating, cleaning the first glass chip 1 by using oxygen plasma for 3min, adding 3 microliter of perfluorooctyl trichlorosilane reagent on the chip, sliding the first glass chip 1 and the second glass chip 2, uniformly smearing the reagent, and standing in a vacuum box for 12 h;
(13) as shown in fig. 3(c) and 3(d), the silane reagent on the surfaces of the first glass chip 1 and the second glass chip 2 is cleaned by acetone, isopropanol and deionized water, and dried by nitrogen. The first glass chip 1 and the second glass chip 2 are assembled face to face by taking 3 mu L of dimethyl silicone oil, and the silicone oil can increase the chip lubrication and reduce the oxygen leakage. A 1% sodium hydroxide solution was added to the sample and reagent wells using a pipette gun to increase the hydrophilicity of this region.
In this embodiment, the image is visibleThe operation of the multielement volume column chip for chemically detecting copper, lead and mercury ions is as follows: as shown in fig. 1, the sample well group is used for storing samples, a pipette is used to inject the samples from the sample injection hole 15 of the first sample well 7, the second sample well 8 or the third sample well 9, and the excess samples flow out from the sample outflow hole 16; reagent well group for storing H2O2Solution, reagent is injected from the reagent injection hole 17 by using a pipette gun, and excess H is injected2O2The liquid flows out from the reagent outflow hole 18; as shown in fig. 4, the ink indicating channel 3 is filled with ink, the ink is injected from the ink inlet hole 13 and flows out from the ink outlet hole 14, and the ink is subjected to O generation2The pushing can move in a continuous S-shaped ink moving channel, and the ink moving distance scales 19 at the upper end and the left and right sides of the ink moving channel are used for indicating the moving distance of the ink; sliding the first glass chip 1 after the ink indication channel 3, the sample cell group and the reagent cell group are filled, wherein the structure of the sliding multi-volume column chip is shown in figure 2, the sample cell group and the reagent cell group are completely overlapped, the ink moving channel is communicated with the reagent cell group, and the sample to be tested and the H cell are connected2O2O produced after mixing2The ink can be pushed to move in the ink moving channel through the channel, and the moving distance can be recorded through the moving distance scales at the upper end and two sides of the channel.
The foregoing is only a preferred embodiment of the present invention, and it should be noted that, for those skilled in the art, various modifications and decorations can be made without departing from the principle of the present invention, and these modifications and decorations should also be regarded as the protection scope of the present invention.
Sequence listing
<110> Nanjing university
<120> multielement volume column chip for visually detecting copper, lead and mercury ions and detection method thereof
<140> 2018103155271
<141> 2018-04-10
<160> 6
<170> SIPOSequenceListing 1.0
<210> 1
<211> 32
<212> DNA
<213> Artificial Sequence (Artificial Sequence)
<400> 1
aaaaaaaaag cttctttcta atacggctta cc 32
<210> 2
<211> 30
<212> DNA
<213> Artificial Sequence (Artificial Sequence)
<400> 2
aaaaaaaaag tagagaaggr atatcactca 30
<210> 3
<211> 33
<212> DNA
<213> Artificial Sequence (Artificial Sequence)
<400> 3
tcatgtttgt ttgttggccc cccttctttc tta 33
<210> 4
<211> 35
<212> DNA
<213> Artificial Sequence (Artificial Sequence)
<400> 4
ggtaagcctg ggcctctttc tttttaagaa agaac 35
<210> 5
<211> 33
<212> DNA
<213> Artificial Sequence (Artificial Sequence)
<400> 5
tgagtgataa agctggccga gcctcttctc tac 33
<210> 6
<211> 10
<212> DNA
<213> Artificial Sequence (Artificial Sequence)
<400> 6
Claims (5)
1. The method for detecting the multi-element volume column chip for visually detecting the copper ions, the lead ions and the mercury ions is characterized in that the multi-element volume column chip for visually detecting the copper ions, the lead ions and the mercury ions comprises a first glass chip and a second glass chip, the first glass chip and the second glass chip are rectangular and have the same size, the inner side of the first glass chip is attached to the inner side of the second glass chip and is in sliding contact with the inner side of the second glass chip, an ink moving channel group, an ink indicating channel and a sample cell group are arranged on the inner side of the first glass chip, the ink moving channel group is arranged on the upper portion of the first glass chip and comprises a first ink moving channel, a second ink moving channel and a third ink moving channel, the first ink moving channel, the second ink moving channel and the third ink moving channel are sequentially arranged in parallel from the left side to the right side of the first glass chip, the sample groove group is positioned at the lower part of the first glass chip and comprises a first sample groove, a second sample groove and a third sample groove, the first sample groove is positioned below the first ink moving channel, the second sample groove is positioned below the second ink moving channel, the third sample groove is positioned below the third ink moving channel, the ink indicating channel is positioned between the ink moving channel group and the sample groove group and is parallel to the upper side and the lower side of the first glass chip, the inner side of the second glass chip is provided with a reagent groove group, the reagent groove group comprises a first reagent groove, a second reagent groove and a third reagent groove, when the first glass chip and the second glass chip are completely overlapped, the sample groove group and the reagent groove group have no overlapped part, when the first glass chip and the second glass chip are aligned, the upper side and the lower side are partially overlapped, and the first sample groove and the first reagent groove are overlapped, the second sample tank, the second reagent tank, the third sample tank and the third reagent tank are also overlapped, the ink moving channel group, the ink indicating channel and the reagent tank group are communicated, the ink indicating channel is provided with an ink water inlet hole and an ink water outlet hole, the first sample tank, the second sample tank and the third sample tank are respectively provided with a sample injection hole and a sample outflow hole, the first reagent tank, the second reagent tank and the third reagent tank are respectively provided with a reagent injection hole and a reagent outflow hole, the ink water inlet hole, the ink water outlet hole, the sample injection hole, the sample outflow hole, the reagent injection hole and the reagent outflow hole are all positioned on the first glass chip, and the ink indicating channel is filled with ink;
the first ink moving channel is used for quantitatively detecting copper ions, the second ink moving channel is used for quantitatively detecting lead ions, the third ink moving channel is used for quantitatively detecting mercury ions, the first ink moving channel, the second ink moving channel and the third ink moving channel are in a continuous S shape and are parallel to the left side and the right side of the first glass chip, an ink moving distance scale is further arranged on the first glass chip and is positioned at the upper end and the left side and the right side of the ink moving channel group;
the first glass chip and the second glass chip are prepared by adopting standard photoetching and wet etching, the inner sides of the first glass chip and the second glass chip are subjected to hydrophobization treatment, and the inner side of the first glass chip and the inner side of the second glass chip are attached through dimethyl silicone oil;
the photoresist adopted by the standard photoetching is SPR220-7, the developing solution is AZ400K, and the etching solution adopted by the wet etching is HF and NH4F and HNO3Mixed solution of HF and NH4F and HNO3The molar ratio of the organic solvent to the organic solvent is 1:0.5:0.75, and the hydrophobic agent adopted in the hydrophobic treatment adopts perfluorooctyl trichlorosilane;
the detection method comprises the following steps:
s1, preparing a multi-element volume column chip: taking the multi-element volume column chip for visually detecting copper ions, lead ions and mercury ions;
s2, preparing a magnetic silica nanoprobe modified by nucleic acid: respectively preparing a nucleic acid modified magnetic silica nanoprobe for detecting copper ions, a nucleic acid modified magnetic silica nanoprobe for detecting lead ions and a nucleic acid modified magnetic silica nanoprobe for detecting mercury ions, specifically:
(a) magnetic Fe prepared by coprecipitation method3O4Nanoparticles;
(b) using magnetic Fe in step (a) by reverse microemulsion method3O4Preparation of magnetic silica nanoparticles from nanoparticlesA seed;
(c) performing Schiff base reaction, and taking glutaraldehyde as a cross-linking agent, and respectively and covalently bonding amino-modified nucleic acid for detecting copper ions, lead ions and mercury ions to the surface of the magnetic silica nanoparticles to obtain nucleic acid-modified magnetic silica nanoprobes for detecting copper ions, lead ions and mercury ions;
wherein the amino modified nucleic acid sequence for detecting copper ions is NH2-(CH2)6-5'-AAAAAAAAAGCTTCTTTCTAATACGGCTTACC-3'、
The amino-modified nucleic acid sequence for detecting lead ions is NH2-(CH2)6-5'-AAAAAAAAAGTAGAGAAGGrATATCACTCA-3'、
The amino-modified nucleic acid sequence for detecting mercury ions is NH2-(CH2)6-5'-TCATGTTTGTTTGTTGGCCCCCCTTCTTTCTTA-3'；
S3, preparing a DNA modified platinum nano probe: preparing platinum nanoparticles by reducing chloroplatinic acid with ascorbic acid, and respectively and covalently bonding DNA modified by sulfydryl and used for detecting copper ions, DNA used for detecting lead ions and DNA used for detecting mercury ions to the surface of the platinum nanoparticles to obtain a DNA modified platinum nanoprobe for detecting copper ions, a DNA modified platinum nanoprobe for detecting lead ions and a DNA modified platinum nanoprobe for detecting mercury ions, wherein the sequence of the DNA modified by sulfydryl and used for detecting copper ions is SH- (CH)2)65'-GGTAAGCCTGGGCCTCTTTCTTTTTAAGAAAGAAC-3', and the sequence of the sulfhydryl modified DNA for detecting lead ions is SH- (CH)2)65'-TGAGTGATAAAGCTGGCCGAGCCTCTTCTCTAC-3', and the sequence of the DNA modified by sulfydryl and used for detecting mercury ions is SH- (CH)2)6-5'-ACAAACATGA-3'；
S4, preparing a composite probe solution: incubating the nucleic acid-modified magnetic silica nanoprobe for detecting copper ions in the step S2 with the DNA-modified platinum nanoprobe for detecting copper ions in the step S3 to form a composite probe for detecting copper ions by DNA double strand complementation, then dispersing the composite probe for detecting copper ions in a buffer solution to prepare a composite probe solution for detecting copper ions, incubating the nucleic acid-modified magnetic silica nanoprobe for detecting lead ions in the step S2 with the DNA-modified platinum nanoprobe for detecting lead ions in the step S3 to form a composite probe for detecting lead ions by DNA double strand complementation, then dispersing the composite probe for detecting lead ions in a buffer solution to prepare a composite probe solution for detecting lead ions, and then dispersing the nucleic acid-modified magnetic silica nanoprobe for detecting mercury ions in the step S2 with the DNA-modified platinum nanoprobe for detecting mercury ions in the step S3 Incubating a DNA-modified platinum nano probe for detecting mercury ions, forming a composite probe for detecting mercury ions through DNA double-strand complementation, and then dispersing the composite probe for detecting mercury ions in a buffer solution to prepare a composite probe solution for detecting mercury ions;
s5, establishing a standard curve: adding copper, lead and mercury analytes with different concentrations into the composite probe solution for detecting copper ions, the composite probe solution for detecting lead ions and the composite probe solution for detecting mercury ions in the step S4 respectively to perform light-shielding oscillation reaction, then performing magnet separation to obtain to-be-detected clear liquids of the copper, lead and mercury analytes with different concentrations, taking the to-be-detected clear liquids to add into the first sample cell, the second sample cell and the third sample cell of the multi-element volume column chip in the step S1 respectively, and adding H into the reagent cell group2O2Solution of the clear solution to be tested for copper ions, the clear solution to be tested for lead ions, the clear solution to be tested for mercury ions and H2O2After the solutions are mixed, recording the advancing distance of the ink column in the multi-element volume column chip, fitting a standard curve equation, and establishing a standard curve;
s6, sample detection: collecting a sample to be detected, filtering to obtain a water sample to be detected, and then adding the water sample to be detected into the composite probe solution for detecting copper ions and the composite probe solution for detecting lead in the step S4 respectivelyCarrying out light-shielding oscillation reaction on the ionic composite probe solution and the composite probe solution for detecting mercury ions, then carrying out magnet separation to obtain a clear liquid to be detected, adding the clear liquid to be detected into the sample tank of the multi-element volume column chip in the step S1, and adding H into the reagent tank2O2A solution, wherein the ink column indicating channel of the multi-element volume column chip is filled with ink, and the clear liquid to be detected and the H2O2And (4) after the solutions are mixed, recording the advancing distance of the ink column in the multi-element volume column chip, and finally analyzing by using the standard curve in the step S5 to obtain the concentrations of the copper, lead and mercury heavy metal ions in the water sample to be detected.
2. The method for detecting the multi-element volume column chip for visually detecting the copper ions, the lead ions and the mercury ions according to claim 1, wherein the molar ratio of the TECP to the DNA adopted when the DNA is modified by the sulfhydryl groups in the step S3 is 5: 1.
3. The method for detecting the multi-element volume column chip for visually detecting the copper ions, the lead ions and the mercury ions according to claim 1, wherein the buffer solution in the step S4 is NaNO containing 150mM3The pH value of the Tris-acetic acid is 8.2, the reaction temperature is 20-25 ℃, and the reaction time is 4 hours.
4. The detection method of the multi-element volume column chip for visual detection of copper, lead and mercury ions according to claim 1, wherein the light-shielding oscillation reaction time in steps S5 and S6 is 30min, and the clear solution to be detected and H are respectively enabled to react by sliding the multi-element volume column chip2O2Mixing the solution, and mixing the clear solution to be tested with H2O2After the solution is mixed, the solution is waited for 10min, and the detection result is recorded.
5. The method for detecting the multi-element volume column chip for visual detection of copper, lead and mercury ions according to claim 1, wherein the components of the reversed-phase microemulsion system in the step S2 comprise 4.42g of Triton X-100 and 18.8mL cyclohexane and 4mL hexanol, wherein the buffer solution adopted in the process of activating amino-modified magnetic silica nanoparticles by glutaraldehyde is a PB buffer solution with the pH value of 7.4, the reaction time is 24h, the use amount of amino-modified nucleic acid is 1 mu mol, and the buffer solution adopted in the reaction process of covalently bonding the amino-modified nucleic acid to the surfaces of the magnetic NaNO silica particles is 150mM NaNO325mM Tris-acetate buffer solution with pH 8.2, at the reaction temperature of 20 ℃ for 12 hours.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201810315527.1A CN108949528B (en) | 2018-04-10 | 2018-04-10 | Multi-element volume column chip for visually detecting copper, lead and mercury ions and detection method thereof |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201810315527.1A CN108949528B (en) | 2018-04-10 | 2018-04-10 | Multi-element volume column chip for visually detecting copper, lead and mercury ions and detection method thereof |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN108949528A CN108949528A (en) | 2018-12-07 |
| CN108949528B true CN108949528B (en) | 2022-02-11 |
Family
ID=64498792
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201810315527.1A Active CN108949528B (en) | 2018-04-10 | 2018-04-10 | Multi-element volume column chip for visually detecting copper, lead and mercury ions and detection method thereof |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN108949528B (en) |
Families Citing this family (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN110286216B (en) * | 2019-05-16 | 2021-10-15 | 中国科学院武汉物理与数学研究所 | A rapidly visualized hemolytic escherichia coli O157: h7 detection method |
| CN116966471A (en) * | 2023-07-20 | 2023-10-31 | 华中科技大学 | Method for degrading halogenated organic pollutants by catalytic reduction with automatic phase separation |
Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN105026933A (en) * | 2012-10-16 | 2015-11-04 | 卫理公会医院 | Multiplexed volumetric bar chart chip for point of care biomarker and/or analyte quantitation |
| WO2016154113A1 (en) * | 2015-03-20 | 2016-09-29 | The Methodist Hospital | Multiplexed volumetric bar chart chip for point of care biomarker and/or analyte quantitation, including competitive control |
-
2018
- 2018-04-10 CN CN201810315527.1A patent/CN108949528B/en active Active
Patent Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN105026933A (en) * | 2012-10-16 | 2015-11-04 | 卫理公会医院 | Multiplexed volumetric bar chart chip for point of care biomarker and/or analyte quantitation |
| US20160097767A1 (en) * | 2012-10-16 | 2016-04-07 | The Methodist Hospital Research Institute | Multiplexed volumetric bar chart chip for point of care biomarker and analyte quantitation |
| WO2016154113A1 (en) * | 2015-03-20 | 2016-09-29 | The Methodist Hospital | Multiplexed volumetric bar chart chip for point of care biomarker and/or analyte quantitation, including competitive control |
Non-Patent Citations (2)
| Title |
|---|
| A versatile quantitation platform based on platinum nanoparticles incorporated volumetric bar-chart chip for highly sensitive assays;Yuzhen Wang et.al.,;《Biosensors and Bioelectronics》;20160531;第85卷;第3.1节、图1、SS1-S3、补充材料部分 * |
| Yuzhen Wang et.al.,.A versatile quantitation platform based on platinum nanoparticles incorporated volumetric bar-chart chip for highly sensitive assays.《Biosensors and Bioelectronics》.2016,第85卷第3.1节、图1、SS1-S3、补充材料部分. * |
Also Published As
| Publication number | Publication date |
|---|---|
| CN108949528A (en) | 2018-12-07 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| Numan et al. | Rationally engineered nanosensors: A novel strategy for the detection of heavy metal ions in the environment | |
| Kung et al. | Microfluidic paper-based analytical devices for environmental analysis of soil, air, ecology and river water | |
| Zohora et al. | Rapid colorimetric detection of mercury using biosynthesized gold nanoparticles | |
| Alberti et al. | Disposable and low-cost colorimetric sensors for environmental analysis | |
| Yogarajah et al. | Detection of trace arsenic in drinking water: challenges and opportunities for microfluidics | |
| Lim et al. | Trends in sensor development toward next-generation point-of-care testing for mercury | |
| Zhou et al. | Selective and sensitive colorimetric sensor of mercury (II) based on gold nanoparticles and 4-mercaptophenylboronic acid | |
| Huang et al. | Development of molecularly imprinted electrochemical sensor with titanium oxide and gold nanomaterials enhanced technique for determination of 4-nonylphenol | |
| CN106442436B (en) | For detecting magnetic quantum dot imprinted material, the Preparation method and use of underwater trace 4- nitrophenol | |
| Devi et al. | A systematic review and meta-analysis of voltammetric and optical techniques for inorganic selenium determination in water | |
| CN108949528B (en) | Multi-element volume column chip for visually detecting copper, lead and mercury ions and detection method thereof | |
| Li et al. | A colorimetric silver nanoparticle-based assay for Hg (II) using lysine as a particle-linking reagent | |
| EP1574854A1 (en) | Immobilizing chemical or biological sensing molecules on semi-conducting nanowires | |
| Pardeshi et al. | Advances in fabrication of molecularly imprinted electrochemical sensors for detection of contaminants and toxicants | |
| Li et al. | Highly sensitive chemiluminescence immunoassay on chitosan membrane modified paper platform using TiO2 nanoparticles/multiwalled carbon nanotubes as label | |
| Li et al. | A surface enhanced Raman scattering quantitative analytical platform for detection of trace Cu coupled the catalytic reaction and gold nanoparticle aggregation with label-free Victoria blue B molecular probe | |
| Liu et al. | Selective and ratiometric fluorescence sensing of bisphenol A in canned food based on portable fluorescent test strips | |
| Zhao et al. | based gold nanoparticles decorated SWCNTs chemiresistive sensor for sensitive detection of As (III) based on electrochemical doping | |
| Alahmad et al. | Molecularly imprinted polymer paper-based analytical devices for biomarkers detection | |
| Sun et al. | Click synthesis of boronic acid-functionalized molecularly imprinted silica nanoparticles with polydopamine coating for enrichment of trace glycoproteins | |
| Xie et al. | Sensitive colorimetric detection of Pb2+ by geometric field amplification and surface plasmon resonance visualization | |
| Wang et al. | A sensing platform for on-site detection of glutathione S-transferase using oxidized Pi@ Ce-doped Zr-based metal-organic frameworks (MOFs) | |
| Wang et al. | Colorimetric detection of Cu2+ based on the inhibition strategy for etching reaction of AgNCs | |
| Abdolmohammad-Zadeh et al. | A chemiluminescence biosensor based on the peroxidase-like property of molybdenum disulfide/zirconium metal-organic framework nanocomposite for diazinon monitoring | |
| Liu et al. | Colorimetric Sensing Platform for Detecting Mercury Ions Based on Self-Assembly of a Two-Dimensional Au Nanoparticle Layer |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant |