CN102200571A - Magnetic relaxation switch-based detection method - Google Patents
Magnetic relaxation switch-based detection method Download PDFInfo
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- CN102200571A CN102200571A CN2010101342205A CN201010134220A CN102200571A CN 102200571 A CN102200571 A CN 102200571A CN 2010101342205 A CN2010101342205 A CN 2010101342205A CN 201010134220 A CN201010134220 A CN 201010134220A CN 102200571 A CN102200571 A CN 102200571A
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Abstract
The invention belongs to the field of magnetic resonance imaging and relates to a magnetic relaxation switch-based detection method. According to the method, based on the change of transverse relaxation time T2 of magnetic nanoparticles in dispersion and aggregation states and caused gray scale change in a T2 weight image, specific target molecules are detected through functionalization modification on the surfaces of the magnetic nanoparticles. The method comprises the following steps of: mixing samples to be detected and corresponding functionalized magnetic nanoparticles; placing the mixture on a minitype detection chip; and detecting in a low field magnetic resonance analyzer. Since a minitype multi-sample detection chip with small size is used in the method, required sample quantity is small and multiple samples can be detected in parallel quickly on the low field magnetic resonance analyzer. According to the method, the problem that conventional imaging equipment has high price and large size, is difficult to operate and not suitable for routine lab application and the problem that the low field magnetic resonance analyzer has a small sample chamber and is not suitable for multi-sample parallel detection can be solved.
Description
Technical field
The invention belongs to the magnetic resonance imaging field, relate to a kind of detection method based on magnetic relaxation switch.Be specifically related to a kind of miniature detection method that is fit to be applied to the low-field nuclear magnetic resonance analyser based on magnetic relaxation switch.
Background technology
Magnetic relaxation switch (Magnetic Relaxation Switches) is a kind of biology sensor based on magnetic particle, its principle of work detects based on the variation of magnetic particle its T2 (TransverseRelaxation Time) T2 under dispersion and aggregating state, by functional modification is carried out on the magnetic particle surface, can be to oligonucleotides, DNA (deoxyribonucleic acid), protein, enzyme, virus, bacterium, bioactive molecules such as antibody detect.With traditional optical detecting method such as uv-vis spectra, fluorescence spectrum is compared, this detection method has quite high sensitivity and specificity, its advantage is the change of magnetic particle reunion back to the relaxation rate (1/T2) of ambient water proton, and do not rely on the detection of optical property, therefore be particularly suitable for the detection of complicated actual sample.Distinguish with its size, magnetic relaxation switch mainly contains following two kinds: a kind ofly be the particle of Nano grade, its reunion causes the shortening of T2, and another is the particle of micron level, and its reunion causes the growth of T2.Use mr imaging technique (MagneticResonance Imaging), the depth difference of the sample of different T2 values gradation of image in the T2 weight map, thus can carry out parallel fast detection to a plurality of samples.Yet general medical magnetic resonance imaging system is bulky, costs an arm and a leg, and daily operation and maintenance cost are higher, is not suitable for Routine Test Lab and uses and operation, uses and development thereby limited it.Prior art also discloses the low-field nuclear magnetic resonance analyser owing to adopt permanent-magnet type magnet, and energy lowering apparatus equipment cost reduces the instrument volume simultaneously, and operation and maintenance are convenient, are suitable for Routine Test Lab and use.But for cost consideration, its sample cavity is general narrower and small, is not suitable for the detection of various product.
Have with the bright relevant prior art of this law:
With Magnetic, Relaxation and Sensor is that the keyword combination is retrieved international monopoly, wherein relates to 1 US20060269965 of patent (Water Relaxation-Based Sensor) of magnetic relaxation switch; Be the keyword sets search with NMR and detection in addition, relate to 1 US7564245 of patent (NMR device fordetection of analytes) of relaxation switch; With the magnetic sensor is that keyword is searched for Chinese patent, have 44 patents, wherein patent of invention is 30,12 of utility model patents, 2 of design patents, but do not see the relevant patent of the miniature detection method based on magnetic relaxation switch that is fit to be applied to the low-field nuclear magnetic resonance analyser.
Summary of the invention
The objective of the invention is provides a kind of detection method based on magnetic relaxation switch, especially a kind of miniature detection method based on magnetic relaxation switch that is fit to be applied to the low-field nuclear magnetic resonance analyser in order to solve the problem that prior art exists.
This method can be applied to show that the fast high-flux of protein interaction detects.
The present invention utilizes the change of magnetic nano-particle its T2 T2 under dispersion and aggregating state, in T2 weight map picture, cause simultaneously the difference of gray scale, by the magnetic nano particle sub-surface is carried out functional modification, thereby specific target molecule is detected.
Particularly, a kind of detection method based on magnetic relaxation switch of the present invention is characterized in that, it comprises, sample to be checked is mixed the back to miniature detection chip with the function corresponding magnetic nano-particle, detects in low magnetic resonance analyser.
Described function corresponding magnetic nano-particle is the magnetic nano-particle of surface modification; Among the present invention, describedly comprise that through magnetic nano particle its surface is respectively through bovine serum albumin antibody and biotin modification.
Described miniature detection chip is the miniature detection chip of various product.
Another object of the present invention provides above-mentioned miniature detection chip and preparation method thereof.
The present invention prepares described miniature detection chip by following method, comprises step:
A. prepare circular PMMA substrate,
B. prepare the upper porous substrate,
C. going up subtegulum heat melts bonding.
Among the present invention, miniature detection chip is to be that PMMA is the circular chip of porous of matrix with polyacrylamide Poly (methyl methacrylate);
Described chip mainly comprises two substrates up and down, the thick 4.8mm of top substrate, the thick 1.6mm of lower substrate.The chip exterior diameter is 13mm, and the hole inside diameter is 1.3mm, hole depth 4.8mm, and the aperture center of circle has 18 cylindrical apertures at a distance of 2mm, is evenly distributed at circular chip middle part with 3 * 6 arrangement modes.
A further object of the present invention provides the preparation method of described functionalized magnetic nano particle.
The present invention prepares functionalized magnetic nano particle by following method, and it comprises step:
A. superparamagnetic nanoparticle is synthetic,
B. the finishing of superparamagnetic nanoparticle.
Functionalized magnetic nano particle of the present invention is to be nuclear with the ferriferrous oxide nano-particle, and glucosan is a shell, and the surface is respectively through the superparamagnetic nanoparticle of bovine serum albumin antibody and biotin modification.Its Fe 3 O 4 magnetic nuclear size is less than 10nm, and the particle ensemble average is of a size of the water soluble particle of 60nm, and wherein tri-iron tetroxide content 49.85%, and saturation magnetization is 32.29emu/g, and its vertical and horizontal relaxivity is respectively 18.51mM
-1S
-1And 269.2mM
-1S
-1
Functionalized magnetic nano particle of the present invention prepares by following step:
(1) superparamagnetic nanoparticle is synthetic;
(2) finishing of superparamagnetic nanoparticle.
Among the present invention, sample to be checked is mixed the back to miniature detection chip with the function corresponding magnetic nano-particle, in low magnetic resonance analyser, detect.The result shows that required sample size is few, can carry out parallel fast detection to a plurality of samples on the low-field nuclear magnetic resonance analyser.
The present invention solves and can solve because conventional imaging equipment price costliness is bulky, and complicated operation is unsuitable for problem and the narrow and small restriction that is unsuitable for the parallel detection of various product of low magnetic resonance imaging instrument sample cavity that Routine Test Lab is used.
Compared with prior art, the present invention has following characteristics:
1. miniature detection chip provided by the invention, volume is tiny, is suitable for the low-field nuclear magnetic resonance analyser.
2. miniature detection chip provided by the invention, the amount of required sample seldom, each sample only needs 6～7 microlitres.
3. miniature detection chip provided by the invention has 18 miniature circular cylindricality apertures, is fit to the parallel detection of various product.
4. functional modification magnetic nano-particle provided by the invention, its Fe 3 O 4 magnetic nuclear size is less than 10nm, and its particle average-size is 60nm.
5. functional modification magnetic nano-particle provided by the invention, wherein tri-iron tetroxide content 49.85%, and saturation magnetization is 32.29emu/g.
6. functional modification magnetic nano-particle provided by the invention, its vertically and the transverse relaxation rate respectively up to 18.51mM
-1S
-1And 269.2mM
-1S
-1
Description of drawings
Fig. 1 is the structural representation of detection chip of the present invention.
Fig. 2 is the particle size distribution figure of magnetic nano-particle of the present invention.
Fig. 3 is magnetic particle magnetization curve figure of the present invention.
Fig. 4 is the thermogravimetric curve figure of magnetic particle of the present invention.
Fig. 5 is the linear fit figure of the magnetic particle images intensity of bovine serum albumin antibody modification of the present invention to bovine serum albumin concentration.
Fig. 6 is the linear fit figure of biotinylation magnetic particle images intensity antibiont fibroin concentration of the present invention.
Specific embodiments
The miniature detection chip of embodiment 1. preparations
(1) preparation of circular PMMA substrate
On the laser rotated bed, be 16mm with the external diameter, internal diameter is that the stainless steel of 13mm is got the hole device, on being the PMMA substrate of 4.8mm and 1.6mm, thickness extracts circular substrate respectively, and with substrate successively at deionized water, absolute ethyl alcohol, ultrasonic (250W) cleaned 20 minutes in the sub-water of degranulation, and dry in convection oven the back.
(2) preparation of upper porous substrate
The chip design figure being drawn with CAD software, adopted laser printing to the scraps of paper, be covered with the scraps of paper on top substrate, on the laser rotated bed is that the fried dough twist brick of 1.3mm changes the hole according to drawing with the external diameter, porous substrates.With substrate successively at deionized water, absolute ethyl alcohol, deionized water for ultrasonic (250W) was cleaned 20 minutes, the back is dry in convection oven.
(3) upward subtegulum is bonding
Align with substrate position about the insulating tape adjustment, and compress, place 90 ℃ of vacuum drying ovens heating after 20 minutes, place the 500g counterweight, continue heating and shed counterweight after 10 minutes, and naturally cool to room temperature, porous chip detection platform promptly with cover glass.
(1) superparamagnetic nanoparticle is synthetic
Adopt the synthetic superparamagnetic nanoparticle of coprecipitation; concrete grammar is as follows; 324.4mg ferric chloride (FeCl36H2O); 119.3mg four water iron protochlorides and 4.5g glucosan (Dextran) (molecular weight=10T) be dissolved in the 10mL deionized water; be cooled to 2～4 ℃; intense mechanical stir and nitrogen protection under adding 2～4 ℃ of ammoniacal liquor of 450 μ L (25～28%), reaction mixture evenly was heated to 75～85 ℃ in one hour after this temperature maintenance 75 minutes.(molecular cut off=300KD) remove impurity and unnecessary glucosan passed through ultrafiltration (300KD) concentrated solution at last by dialysis after reactant liquor naturally cooled to room temperature.
(2) finishing of superparamagnetic nanoparticle
Synthetic superparamagnetic nanoparticle (7mmol/L Fe) is received oxidation 1 hour through the 10.7mg periodic acid earlier in the 5mL step (1), reaction mixture is got 1mL after impurity is removed in dialysis (molecular cut off 14KD), add 100 μ L bovine serum albumin antibody (anti-BSA) (2mg/mL), it is fixing with sodium borohydride (1mg/mL) reduction after 24 hours to stir reaction down, and product is at last with dialysis and the ultrafiltration (purifying of molecular cut off=300KD).
Add 8mL NaOH (0.5mol/L) and 2mL epichlorokydrin (epichlorohydrin) in the superparamagnetic nanoparticle that in 1mL step (1), synthesizes, said mixture at room temperature stirred 24 hours, add 5mL ammoniacal liquor (25～28%) and continue to stir 12 hours, excessive epichlorokydrin and ammoniacal liquor are by dialysis (molecular cut off=14KD) go out.The above-mentioned reactant liquor of 4mL adds 400 μ L sodium hydroxide solutions (1mol/L) the pH value is transferred to 8.0-8.3, add 1mL subsequently and contain 1.2mg biotin (Biotin), 1.0mg 1-ethyl-3-(3-dimethyl aminopropyl)-carbodiimides (EDC), 0.6mg dimethyl sulfoxide (DMSO) (DMSO) solution of N-hydroxy-succinamide (NHS) stirred 6 hours under the room temperature.(10mmol/L, (molecular cut off=300KD) goes out decon to reactant liquor in pH=7.4) down dialysis at PBS buffer solution.
The detection of embodiment 3. T2s
The PBS solution of the bovine serum albumin of variable concentrations (BSA) and avidin (Avidin) mixes with the magnetic nano-particle of bovine serum albumin antibody modification and biotinylated magnetic nano-particle respectively and is incorporated under 38 ℃ of waters bath with thermostatic control constant temperature after 90 minutes, in magnetic field intensity is to measure its T2 in the low magnetic resonance analyser of 0.47 tesla, and used pulse train is Carr-Purcell-Meiboom-Gill (CPMG) sequence.
Obtaining of embodiment 4.T2 weight map picture
The avidin that concentration range is respectively the bovine serum albumin of 0～1.0 μ mol/L and 0～0.6 μ mol/L mixes with the magnetic nano-particle of bovine serum albumin antibody modification and biotinylated magnetic nano-particle respectively and moves liquid to the aperture of miniature detection chip, constant temperature is 60 minutes under 38 ℃ of constant temperature air baths, in being the low magnetic resonance analyser of 0.47 tesla, magnetic field intensity carries out the imaging of T2 weight, used pulse train is spin echo spin echo (SE), imaging parameters: repetition time TR=3000ms, echo time TE=30ms, multiplicity NS=4, imaging thickness=5mm, imaging visual field FOV=8mm * 12mm, pixel matrices=80 * 120.
Claims (10)
1. the detection method based on magnetic relaxation switch is characterized in that, it comprises, sample to be checked is mixed the back to miniature detection chip with the function corresponding magnetic nano-particle, detects in low magnetic resonance analyser;
Described function corresponding magnetic nano-particle is the magnetic nano-particle of surface modification;
Described miniature detection chip is the miniature detection chip of various product.
2. by the described method of claim 1, it is characterized in that described miniature detection chip is to be the chip of matrix with polyacrylamide PMMA.
3. by claim 1 or 2 described methods, it is characterized in that described miniature detection chip is made of the center of circle substrate by 13mm of two diameters up and down.
4. by the described method of claim 3, it is characterized in that, the described subtegulum of going up, its thickness is respectively 4.8mm and 1.6mm.
5. by the described method of claim 3, it is characterized in that the described substrate of going up is provided with the cylindrical aperture that 18 diameters are 1.3mm, hole depth 4.8mm, the center of circle and is uniformly distributed in the middle part of the substrate with 3x 6 forms at a distance of 2mm between the hole.
6. by the described method of claim 1, it is characterized in that described miniature detection chip prepares by following method:
The preparation of a. circular PMMA substrate;
B. the preparation of upper porous substrate;
C. going up subtegulum heat melts bonding.
7. by the described method of claim 1, it is characterized in that described magnetic nano-particle: it is formed with the ferriferrous oxide nano-particle is nuclear, and size is less than 10 nanometers, and outside is shell with the glucosan, and the mean grain size of whole particle is 60 nanometers.
8. by the described method of claim 7, it is characterized in that its tri-iron tetroxide content of described magnetic nano-particle is 49.85%, saturation magnetization is 32.29emu/g, and its vertical and horizontal relaxivity is respectively 18.51mM
-1S
-1And 269.2mM
-1S
-1
9. by the described method of claim 1, it is characterized in that its surface of described magnetic nano-particle is respectively through bovine serum albumin antibody and biotin modification.
10. by the described method of claim 1, it is characterized in that described magnetic nano-particle prepares by following step:
A. superparamagnetic nanoparticle is synthetic;
B. the finishing of superparamagnetic nanoparticle.
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Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103303013A (en) * | 2013-06-06 | 2013-09-18 | 中国科学技术大学 | Invisible photonic crystal printing method |
| CN108333536A (en) * | 2017-01-20 | 2018-07-27 | 国家纳米科学中心 | The Magnetic Sensor and its construction method, purposes read based on longitudinal relaxation time signal |
Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US20030009297A1 (en) * | 2001-03-26 | 2003-01-09 | Konstantin Mirotchnik | Determination of oil and water compositions of oil/water emulsions using low field NMR Relaxometry |
| CN101253416A (en) * | 2005-05-09 | 2008-08-27 | 通用医疗公司 | Water relaxation-based sensors |
| US20080204022A1 (en) * | 2006-08-21 | 2008-08-28 | Sillerud Laurel O | Biological detector and method |
| CN101509919A (en) * | 2009-03-12 | 2009-08-19 | 湖南工业大学 | Method for producing water- soluble magnetic nanoparticle for detecting SQUID |
-
2010
- 2010-03-26 CN CN2010101342205A patent/CN102200571A/en active Pending
Patent Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US20030009297A1 (en) * | 2001-03-26 | 2003-01-09 | Konstantin Mirotchnik | Determination of oil and water compositions of oil/water emulsions using low field NMR Relaxometry |
| CN101253416A (en) * | 2005-05-09 | 2008-08-27 | 通用医疗公司 | Water relaxation-based sensors |
| US20080204022A1 (en) * | 2006-08-21 | 2008-08-28 | Sillerud Laurel O | Biological detector and method |
| CN101509919A (en) * | 2009-03-12 | 2009-08-19 | 湖南工业大学 | Method for producing water- soluble magnetic nanoparticle for detecting SQUID |
Non-Patent Citations (2)
| Title |
|---|
| 刘颖: "基于表面分子开关的生物传感器新方法研究", 《中国优秀博士学位论文全文数据库》, no. 6, 15 June 2007 (2007-06-15), pages 57 - 59 * |
| 孙宁等: "超顺磁性纳米Fe3O4颗粒感生的横向弛豫", 《材料科学与工程学报》, vol. 27, no. 4, 31 August 2009 (2009-08-31), pages 506 - 509 * |
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103303013A (en) * | 2013-06-06 | 2013-09-18 | 中国科学技术大学 | Invisible photonic crystal printing method |
| CN108333536A (en) * | 2017-01-20 | 2018-07-27 | 国家纳米科学中心 | The Magnetic Sensor and its construction method, purposes read based on longitudinal relaxation time signal |
| CN108333536B (en) * | 2017-01-20 | 2021-11-19 | 国家纳米科学中心 | Magnetic sensor based on longitudinal relaxation time signal readout and construction method and application thereof |
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Application publication date: 20110928 |