CN117538294B - Conical optical fiber sensor for detecting cholesterol concentration based on MZI-LSPR and preparation method - Google Patents
Conical optical fiber sensor for detecting cholesterol concentration based on MZI-LSPR and preparation method Download PDFInfo
- Publication number
- CN117538294B CN117538294B CN202410009087.2A CN202410009087A CN117538294B CN 117538294 B CN117538294 B CN 117538294B CN 202410009087 A CN202410009087 A CN 202410009087A CN 117538294 B CN117538294 B CN 117538294B
- Authority
- CN
- China
- Prior art keywords
- optical fiber
- lspr
- tapered optical
- solution
- mzi
- 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
- HVYWMOMLDIMFJA-DPAQBDIFSA-N cholesterol Chemical compound C1C=C2C[C@@H](O)CC[C@]2(C)[C@@H]2[C@@H]1[C@@H]1CC[C@H]([C@H](C)CCCC(C)C)[C@@]1(C)CC2 HVYWMOMLDIMFJA-DPAQBDIFSA-N 0.000 title claims abstract description 94
- 239000013307 optical fiber Substances 0.000 title claims abstract description 53
- 235000012000 cholesterol Nutrition 0.000 title claims abstract description 47
- 238000002360 preparation method Methods 0.000 title claims abstract description 11
- 239000000835 fiber Substances 0.000 claims abstract description 36
- 239000000243 solution Substances 0.000 claims abstract description 33
- 239000010931 gold Substances 0.000 claims abstract description 15
- 230000004048 modification Effects 0.000 claims abstract description 12
- 238000012986 modification Methods 0.000 claims abstract description 12
- WHGYBXFWUBPSRW-FOUAGVGXSA-N beta-cyclodextrin Chemical compound OC[C@H]([C@H]([C@@H]([C@H]1O)O)O[C@H]2O[C@@H]([C@@H](O[C@H]3O[C@H](CO)[C@H]([C@@H]([C@H]3O)O)O[C@H]3O[C@H](CO)[C@H]([C@@H]([C@H]3O)O)O[C@H]3O[C@H](CO)[C@H]([C@@H]([C@H]3O)O)O[C@H]3O[C@H](CO)[C@H]([C@@H]([C@H]3O)O)O3)[C@H](O)[C@H]2O)CO)O[C@@H]1O[C@H]1[C@H](O)[C@@H](O)[C@@H]3O[C@@H]1CO WHGYBXFWUBPSRW-FOUAGVGXSA-N 0.000 claims abstract description 11
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Chemical compound O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims abstract description 9
- 239000008367 deionised water Substances 0.000 claims abstract description 8
- 229910021641 deionized water Inorganic materials 0.000 claims abstract description 8
- NLJMYIDDQXHKNR-UHFFFAOYSA-K sodium citrate Chemical compound O.O.[Na+].[Na+].[Na+].[O-]C(=O)CC(O)(CC([O-])=O)C([O-])=O NLJMYIDDQXHKNR-UHFFFAOYSA-K 0.000 claims abstract description 5
- 239000001509 sodium citrate Substances 0.000 claims abstract description 5
- 238000009835 boiling Methods 0.000 claims abstract description 4
- 239000011247 coating layer Substances 0.000 claims abstract description 4
- 238000001914 filtration Methods 0.000 claims abstract description 4
- FDWREHZXQUYJFJ-UHFFFAOYSA-M gold monochloride Chemical compound [Cl-].[Au+] FDWREHZXQUYJFJ-UHFFFAOYSA-M 0.000 claims abstract description 4
- 239000011259 mixed solution Substances 0.000 claims abstract description 4
- 238000007747 plating Methods 0.000 claims abstract description 4
- 238000010992 reflux Methods 0.000 claims abstract description 4
- 238000003756 stirring Methods 0.000 claims abstract description 4
- 238000003286 fusion draw glass process Methods 0.000 claims abstract description 3
- 238000005406 washing Methods 0.000 claims abstract description 3
- NCEGJIHRQBRVJQ-UHFFFAOYSA-N 2-amino-3-[3-[2-(phosphonomethyl)phenyl]phenyl]propanoic acid Chemical compound OC(=O)C(N)CC1=CC=CC(C=2C(=CC=CC=2)CP(O)(O)=O)=C1 NCEGJIHRQBRVJQ-UHFFFAOYSA-N 0.000 claims abstract 7
- 238000000034 method Methods 0.000 claims description 19
- 238000005253 cladding Methods 0.000 claims description 10
- 230000003595 spectral effect Effects 0.000 claims description 9
- 230000009466 transformation Effects 0.000 claims description 8
- 238000004422 calculation algorithm Methods 0.000 claims description 6
- 238000012937 correction Methods 0.000 claims description 5
- 238000002791 soaking Methods 0.000 claims description 5
- 239000011248 coating agent Substances 0.000 claims description 4
- 238000000576 coating method Methods 0.000 claims description 4
- 238000004519 manufacturing process Methods 0.000 claims description 4
- 239000002245 particle Substances 0.000 claims description 4
- 238000012545 processing Methods 0.000 claims description 4
- 230000009471 action Effects 0.000 claims description 3
- 239000010410 layer Substances 0.000 claims description 3
- 238000001755 magnetron sputter deposition Methods 0.000 claims description 3
- 238000000605 extraction Methods 0.000 claims description 2
- 230000035945 sensitivity Effects 0.000 description 10
- 229920000858 Cyclodextrin Polymers 0.000 description 8
- 239000001116 FEMA 4028 Substances 0.000 description 8
- 235000011175 beta-cyclodextrine Nutrition 0.000 description 8
- 229960004853 betadex Drugs 0.000 description 8
- HZAXFHJVJLSVMW-UHFFFAOYSA-N 2-Aminoethan-1-ol Chemical compound NCCO HZAXFHJVJLSVMW-UHFFFAOYSA-N 0.000 description 7
- 239000011159 matrix material Substances 0.000 description 7
- 238000001228 spectrum Methods 0.000 description 5
- 239000008280 blood Substances 0.000 description 4
- 210000004369 blood Anatomy 0.000 description 4
- VHJLVAABSRFDPM-QWWZWVQMSA-N dithiothreitol Chemical compound SC[C@@H](O)[C@H](O)CS VHJLVAABSRFDPM-QWWZWVQMSA-N 0.000 description 4
- 238000005259 measurement Methods 0.000 description 4
- 230000008859 change Effects 0.000 description 3
- 238000013016 damping Methods 0.000 description 3
- 238000001514 detection method Methods 0.000 description 3
- 238000010586 diagram Methods 0.000 description 3
- 230000004927 fusion Effects 0.000 description 3
- 230000008569 process Effects 0.000 description 3
- 125000003396 thiol group Chemical group [H]S* 0.000 description 3
- 238000004364 calculation method Methods 0.000 description 2
- 230000000694 effects Effects 0.000 description 2
- 230000005684 electric field Effects 0.000 description 2
- 230000003993 interaction Effects 0.000 description 2
- 239000000463 material Substances 0.000 description 2
- 125000002924 primary amino group Chemical group [H]N([H])* 0.000 description 2
- 230000001105 regulatory effect Effects 0.000 description 2
- 238000003860 storage Methods 0.000 description 2
- 238000013519 translation Methods 0.000 description 2
- AUVSUPMVIZXUOG-UHFFFAOYSA-N (4-sulfanylphenyl)boronic acid Chemical compound OB(O)C1=CC=C(S)C=C1 AUVSUPMVIZXUOG-UHFFFAOYSA-N 0.000 description 1
- ZOXJGFHDIHLPTG-UHFFFAOYSA-N Boron Chemical group [B] ZOXJGFHDIHLPTG-UHFFFAOYSA-N 0.000 description 1
- 208000024172 Cardiovascular disease Diseases 0.000 description 1
- 208000031226 Hyperlipidaemia Diseases 0.000 description 1
- 206010020772 Hypertension Diseases 0.000 description 1
- JXASPPWQHFOWPL-UHFFFAOYSA-N Tamarixin Natural products C1=C(O)C(OC)=CC=C1C1=C(OC2C(C(O)C(O)C(CO)O2)O)C(=O)C2=C(O)C=C(O)C=C2O1 JXASPPWQHFOWPL-UHFFFAOYSA-N 0.000 description 1
- 238000010521 absorption reaction Methods 0.000 description 1
- 230000009286 beneficial effect Effects 0.000 description 1
- 239000012503 blood component Substances 0.000 description 1
- KGBXLFKZBHKPEV-UHFFFAOYSA-N boric acid Chemical compound OB(O)O KGBXLFKZBHKPEV-UHFFFAOYSA-N 0.000 description 1
- 239000004327 boric acid Substances 0.000 description 1
- 229910052796 boron Inorganic materials 0.000 description 1
- 125000003178 carboxy group Chemical group [H]OC(*)=O 0.000 description 1
- 238000006243 chemical reaction Methods 0.000 description 1
- 238000004737 colorimetric analysis Methods 0.000 description 1
- 230000001808 coupling effect Effects 0.000 description 1
- 230000007423 decrease Effects 0.000 description 1
- 230000007547 defect Effects 0.000 description 1
- 238000002848 electrochemical method Methods 0.000 description 1
- 230000005284 excitation Effects 0.000 description 1
- 238000002474 experimental method Methods 0.000 description 1
- 238000007306 functionalization reaction Methods 0.000 description 1
- PCHJSUWPFVWCPO-UHFFFAOYSA-N gold Chemical compound [Au] PCHJSUWPFVWCPO-UHFFFAOYSA-N 0.000 description 1
- 229910052737 gold Inorganic materials 0.000 description 1
- 230000036541 health Effects 0.000 description 1
- 238000012804 iterative process Methods 0.000 description 1
- 239000002184 metal Substances 0.000 description 1
- 229910052751 metal Inorganic materials 0.000 description 1
- 239000002082 metal nanoparticle Substances 0.000 description 1
- 239000000203 mixture Substances 0.000 description 1
- 238000012544 monitoring process Methods 0.000 description 1
- 239000002105 nanoparticle Substances 0.000 description 1
- 230000007935 neutral effect Effects 0.000 description 1
- 125000004433 nitrogen atom Chemical group N* 0.000 description 1
- 238000010606 normalization Methods 0.000 description 1
- 210000000056 organ Anatomy 0.000 description 1
- 238000004088 simulation Methods 0.000 description 1
- 238000011895 specific detection Methods 0.000 description 1
- 239000000126 substance Substances 0.000 description 1
- PXQLVRUNWNTZOS-UHFFFAOYSA-N sulfanyl Chemical compound [SH] PXQLVRUNWNTZOS-UHFFFAOYSA-N 0.000 description 1
- 238000012546 transfer Methods 0.000 description 1
Classifications
-
- C—CHEMISTRY; METALLURGY
- C03—GLASS; MINERAL OR SLAG WOOL
- C03C—CHEMICAL COMPOSITION OF GLASSES, GLAZES OR VITREOUS ENAMELS; SURFACE TREATMENT OF GLASS; SURFACE TREATMENT OF FIBRES OR FILAMENTS MADE FROM GLASS, MINERALS OR SLAGS; JOINING GLASS TO GLASS OR OTHER MATERIALS
- C03C25/00—Surface treatment of fibres or filaments made from glass, minerals or slags
- C03C25/66—Chemical treatment, e.g. leaching, acid or alkali treatment
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N21/00—Investigating or analysing materials by the use of optical means, i.e. using sub-millimetre waves, infrared, visible or ultraviolet light
- G01N21/17—Systems in which incident light is modified in accordance with the properties of the material investigated
- G01N21/25—Colour; Spectral properties, i.e. comparison of effect of material on the light at two or more different wavelengths or wavelength bands
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N21/00—Investigating or analysing materials by the use of optical means, i.e. using sub-millimetre waves, infrared, visible or ultraviolet light
- G01N21/17—Systems in which incident light is modified in accordance with the properties of the material investigated
- G01N21/41—Refractivity; Phase-affecting properties, e.g. optical path length
- G01N21/45—Refractivity; Phase-affecting properties, e.g. optical path length using interferometric methods; using Schlieren methods
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N21/00—Investigating or analysing materials by the use of optical means, i.e. using sub-millimetre waves, infrared, visible or ultraviolet light
- G01N21/17—Systems in which incident light is modified in accordance with the properties of the material investigated
- G01N21/55—Specular reflectivity
- G01N21/552—Attenuated total reflection
- G01N21/553—Attenuated total reflection and using surface plasmons
- G01N21/554—Attenuated total reflection and using surface plasmons detecting the surface plasmon resonance of nanostructured metals, e.g. localised surface plasmon resonance
-
- G—PHYSICS
- G02—OPTICS
- G02B—OPTICAL ELEMENTS, SYSTEMS OR APPARATUS
- G02B6/00—Light guides; Structural details of arrangements comprising light guides and other optical elements, e.g. couplings
- G02B6/24—Coupling light guides
- G02B6/245—Removing protective coverings of light guides before coupling
-
- G—PHYSICS
- G02—OPTICS
- G02B—OPTICAL ELEMENTS, SYSTEMS OR APPARATUS
- G02B6/00—Light guides; Structural details of arrangements comprising light guides and other optical elements, e.g. couplings
- G02B6/24—Coupling light guides
- G02B6/255—Splicing of light guides, e.g. by fusion or bonding
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N21/00—Investigating or analysing materials by the use of optical means, i.e. using sub-millimetre waves, infrared, visible or ultraviolet light
- G01N21/17—Systems in which incident light is modified in accordance with the properties of the material investigated
- G01N21/41—Refractivity; Phase-affecting properties, e.g. optical path length
- G01N21/45—Refractivity; Phase-affecting properties, e.g. optical path length using interferometric methods; using Schlieren methods
- G01N2021/458—Refractivity; Phase-affecting properties, e.g. optical path length using interferometric methods; using Schlieren methods using interferential sensor, e.g. sensor fibre, possibly on optical waveguide
Abstract
The invention discloses a tapered optical fiber sensor for detecting cholesterol concentration based on MZI-LSPR and a preparation method thereof, belonging to the technical field of optical fiber sensing; the preparation method comprises the following steps: removing the coating layer of the single-mode fiber, and then carrying out fusion drawing to obtain a tapered optical fiber with the optical fiber waist diameter smaller than 20 um; dissolving gold chloride in deionized water, boiling under reflux, adding sodium citrate under stirring, reacting the solution until the color changes from pale yellow to dark red, and filtering to obtain AuNPs; plating an Au film on the surface of the waist, immersing the waist in a DTT solution for modification, and immersing in an AuNPs solution for modification; immersing the waist modified by AuNPs in a mixed solution of PMBA and MEA for modification; and immersing the tapered optical fiber waist modified by PMBA molecules in beta-CD solution, and then washing the PMBA molecules which are not combined on the surface of the tapered optical fiber core by deionized water to prepare the tapered optical fiber sensor.
Description
Technical Field
The invention belongs to the technical field of optical fiber sensing, and particularly relates to a tapered optical fiber sensor for detecting cholesterol concentration based on MZI-LSPR and a preparation method thereof.
Background
Blood is the most important tissue in the circulatory system of the human body, throughout the entire life. The human blood contains various biochemical indexes required by biological organs, such as cholesterol, which is one of the most common substances in human blood and plays a vital role in the human life cycle. Once a person suffers from hypertension, hyperlipidemia and cardiovascular disease, they often rapidly cause changes in blood components, severely threatening the health of the person. Therefore, it is important to detect biochemical indexes of blood. Currently, there are many methods for realizing single parameter detection of cholesterol concentration, such as electrochemical method, colorimetric method, etc., which are effective, but require highly skilled laboratory staff, and have the time-consuming problem; and the use of the optical fiber sensor on the basis also has certain problems at present, such as low sensitivity, and the actual application value of the sensor is directly influenced.
Disclosure of Invention
Aiming at the defects of the prior art, the invention aims to provide a tapered optical fiber sensor for detecting cholesterol concentration based on MZI-LSPR and a preparation method thereof, which solve the problems in the prior art.
The aim of the invention can be achieved by the following technical scheme:
a preparation method of a tapered optical fiber sensor for detecting cholesterol concentration based on MZI-LSPR comprises the following steps:
s1, removing a coating layer of a single-mode fiber, and then carrying out fusion drawing to ensure that the diameters of a cladding layer and a fiber core of the fiber are gradually reduced along the axial direction of the fiber to form a tapered fiber with the waist diameter smaller than 20 um;
s2, dissolving gold chloride in deionized water, boiling under reflux, adding sodium citrate under stirring, reacting the solution until the color changes from pale yellow to dark red, and filtering to obtain AuNPs;
s3, plating an Au film on the surface of the tapered optical fiber waist, immersing the tapered optical fiber waist in a DTT solution for modification, and immersing in an AuNPs solution for modification;
s4, soaking the tapered optical fiber waist modified by AuNPs in a mixed solution of PMBA and MEA for modification;
s5, soaking the tapered optical fiber waist modified by PMBA molecules in beta-CD solution, and then washing the PMBA molecules which are not combined on the tapered optical fiber surface by deionized water to prepare the tapered optical fiber sensor.
Further, in S2, the particle size of the AuNPs prepared was 48nm.
Further, in S3, an Au film is plated on the tapered optical fiber waist surface using a magnetron sputtering coater.
Further, in S4, PMBA concentration is 5mM and MEA concentration is 10mM.
Further, the beta-CD solution had a concentration of 0.01M and a pH of 7.8.
A tapered optical fiber sensor for detecting cholesterol concentration based on MZI-LSPR is prepared by using the preparation method.
The method for detecting the cholesterol concentration by using the conical optical fiber sensor for detecting the cholesterol concentration based on the MZI-LSPR comprises the following steps of: :
step one, connecting a spectrometer with a conical optical fiber sensor, immersing a sensing area of the conical optical fiber sensor into cholesterol solution, and under the action of a light source, reading a resonance trough by the spectrometer and transmitting the resonance trough to a computer; and by continuously increasing the concentration of the cholesterol solution, a plurality of resonance trough signals are obtained and reserved;
performing Fourier transform on the monitored resonance trough, extracting a LSPR signal after the transformation, and then performing inverse Fourier transform on the LSPR signal to obtain a required LSPR signal;
step three, performing parameter extraction on the LSPR signal obtained in the step two by utilizing a spectral curve correction algorithm based on four parameters, and fitting the LSPR signal with high precision;
and fourthly, analyzing and processing the LSPR signals extracted from the resonance trough signals to obtain the wavelength shift of the LSPR signals so as to reversely deduce the concentration of the cholesterol solution.
The invention has the beneficial effects that:
1. the tapered optical fiber sensor for detecting cholesterol concentration based on the MZI-LSPR can generate MZI effect by utilizing the tapered structure so as to be combined with the LSPR for temperature compensation; and the spectrum in a smaller wave band of LSPR absorption can be excited by introducing gold nano particles, so that the sensitivity of the sensor is greatly improved.
2. The method for detecting the cholesterol concentration by using the tapered optical fiber sensor provided by the invention utilizes the FFT to separate two parameters of temperature and sensitivity, displays a sensitivity matrix for simultaneously detecting the two parameters, solves the problem of temperature interference of the sensor based on RI change, and performs temperature compensation.
3. According to the method for detecting the cholesterol concentration by using the tapered optical fiber sensor, provided by the invention, the LSPR signal can be extracted by FFT (fast Fourier transform) only by using one spectrometer, and then the LSPR signal with high precision is fitted by using a spectral curve correction algorithm model based on four parameters, so that the cholesterol concentration is detected.
Drawings
In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly described, and it will be obvious to those skilled in the art that other drawings can be obtained according to these drawings without inventive effort.
FIG. 1 is a schematic diagram of a tapered fiber optic sensor of the present invention;
fig. 2 is a schematic diagram of a strong electric field generated between Au film and AuNPs in the present invention;
FIG. 3 is a flow chart of the fabrication of a tapered fiber sensor of the present invention;
FIG. 4 is an exemplary diagram of an FFT transform of the present invention;
FIG. 5 is a graph of MZI signals at different temperatures according to the present invention;
FIG. 6 is a graph of MZI signals at different cholesterol concentrations according to the present invention;
FIG. 7 is a graph of SPR signals at various temperatures in accordance with the present invention;
FIG. 8 is a graph of SPR signals at various cholesterol concentrations according to the present invention;
FIG. 9 is a flow chart of an experiment of the present invention;
fig. 10 is an exemplary graph of simulation data of a four-parameter based spectral curve (4-PSCR) correction algorithm model of the present invention.
Detailed Description
The following description of the embodiments of the present invention will be made clearly and completely with reference to the accompanying drawings, in which it is apparent that the embodiments described are only some embodiments of the present invention, but not all embodiments. All other embodiments, which can be made by those skilled in the art based on the embodiments of the invention without making any inventive effort, are intended to be within the scope of the invention.
As shown in FIG. 1, a tapered fiber sensor for detecting cholesterol concentration based on MZI-LSPR comprises a tapered fiber with a waist diameter smaller than 20um, forming a tapered MZI (Mach-Zehnder interferometer effect) sensor; and the tapered fiber waist is modified by using metal nano particles (AuNPs), and beta-cyclodextrin (beta-CD) molecules are combined with the waist by a covalent bond method, so that the tapered fiber sensor is formed, and can be used for detecting cholesterol concentration.
When the waist diameter of the tapered optical fiber is less than 20 μm, the surface evanescent region of the visible light band (LSPR operating band) can be excited more effectively. And as the waist diameter decreases, the sensitivity of the refractive index increases significantly.
Example 1 is provided below to prepare the above-described tapered fiber sensor for detecting cholesterol concentration based on MZI-LSPR;
example 1
As shown in fig. 3, the preparation method of the tapered optical fiber sensor for detecting cholesterol concentration based on MZI-LSPR comprises the following steps:
s1, selecting a single mode fiber, wherein the type of the selected fiber is SMF-28e, the refractive index of the fiber core is 1.446, the refractive index of the cladding is 1.439, the diameter of the fiber core is 8.2um, and the diameter of the cladding is 125um; the single-mode fiber is respectively a fiber core, a cladding and a coating from inside to outside, the cladding of the single-mode fiber is removed by taking a fusion pulling method as a basic principle, the diameters of the cladding and the fiber core of the single-mode fiber are gradually reduced along the axial direction of the fiber by utilizing an AFBT-8000 fiber fusion tapering machine, and finally the waist diameter of the fiber is 10um, so that a tapered fiber is formed;
s2, dissolving gold chloride in deionized water, and boiling under reflux; adding sodium citrate under vigorous stirring, reacting the solution for 15 minutes until the color changes from pale yellow to dark red, regulating the particle size in a wider range by regulating the proportion of sodium citrate to Au, preparing AuNPs with the particle size of 48nm, and filtering the synthesized AuNPs to purify a sample;
s3, plating an Au film on the surface of the waist of the tapered optical fiber by using a magnetron sputtering coating machine, and fixing the tapered optical fiber plated with the Au film on a lifting coating machine, so that the upper and lower heights of the sensor can be accurately controlled, and the waist of the tapered optical fiber is ensured to be fully immersed in Dithiothreitol (DTT) solution for 24 hours. After DTT modification, free sulfhydryl (-HS) is formed on the surface of the Au film, as shown in figure 3; then soaking the mixture in AuNPs solution for 12 hours, wherein free sulfhydryl (-HS) on the surface of the Au film is used for realizing the connection between the AuNPs and the surface of the Au film;
s4, immersing the tapered optical fiber waist functionalized in the step S3 in a mixed solution of 5 milliliters of p-mercaptophenylboronic acid (PMBA) (5 mM) solution and 5 Milliliters of Ethanolamine (MEA) (10 mM) solution for 12 hours, and combining the PMBA with AuNPs; wherein the MEA molecule is introduced in the functionalization process, and interaction between boric acid and o-amino can occur because the MEA molecule contains amino; the charge transfer from the N atom to the boron atom can reduce the acidity coefficient (PKA) value of Re-action combination between the PMBA and the cis-diol structure, and prevent the combination between PMBA molecules;
s5, combining PMBA and beta-CD can carry out AUNPs surface modification in a neutral environment; immersing the tapered fiber waist modified by PMBA molecules in S4 in 0.01M beta-CD solution (dissolved in pH=7.8) for 12h; the tapered fiber can then be rinsed slowly with deionized water before measurement to remove unbound PMBA molecules, and finally a tapered fiber sensor is fabricated.
As shown in fig. 2, there is leakage of the evanescent field in the metal layer, which illustrates that AuNPs and Au film modified surfaces can simultaneously produce a coupling effect. After the AuNPs are introduced, a strong electric field is generated between the Au film and the AuNPs, which not only can enhance the interaction with surrounding media and improve the sensitivity of the sensor, but also can excite LSPR resonance. And then combining PMBA with AuNPs through sulfhydryl (-SH), and combining PMBA with beta-CD through carboxyl and amino reaction to form a final structure, thereby realizing specific detection of cholesterol concentration.
Example 2
In this example, cholesterol concentration was measured using the tapered optical fiber sensor prepared in example 1.
When the experimental measurement is carried out, the concentration of the cholesterol solution is continuously increased, the cholesterol combined with beta-CD is continuously increased, the structure of the sensitive film outside the coating layer is changed, and the wavelength position of the resonance trough is also moved. The concentration of cholesterol can be reversely deduced by monitoring the wavelength shift, namely, the measurement of cholesterol concentration is realized. When light is transmitted into the tapered region, a portion of the light enters the cladding of the tapered region and a portion of the light enters the air core of the tapered region. Light entering the cladding will be affected by the external environment as follows. At the second fusion point of the conical region and the untapered region, light is transmitted in the cladding, and hollow cores of the untapered region are converged to generate MZI interference; the resonance trough is the superposition of the MZI signal and the LSPR signal;
as shown in fig. 9, the method for cholesterol concentration detection using the tapered optical fiber sensor prepared in example 1 includes the steps of:
step one, connecting a spectrometer with a conical optical fiber sensor, immersing a sensing area of the conical optical fiber sensor into cholesterol solution, and transmitting a read resonance trough to a computer by the spectrometer under the action of a light source; by continuously increasing the concentration of the cholesterol solution, a plurality of resonance trough signals are obtained and reserved;
step two, the resonance trough in the S1 is superposition of MZI signals and LSPR signals, in order to separate the two signals to obtain the required LSPR signals, the monitored resonance trough is subjected to Fourier transform (FFT) to extract the LSPR signals after the transformation, and then the monitored resonance trough is subjected to inverse Fourier transform to obtain the required LSPR signals;
the spectrometer can read the resonance trough and pass it to a computer, as can be seen from fig. 4 (a), which then processes the signals. Taking the curve with the refractive index of 1.33 in fig. 4 (a) as an example, normalization is performed on the curve, and fourier transform is performed on the curve, so that the result is known from fig. 4 (b); next, observing the features of the extracted SPR signal and MZI signal, and processing (a) in fig. 4 by using a band-pass filter to obtain (c) in fig. 4 and (d) in fig. 4;
then, the fiber was slowly heated to obtain MZI signals and SPR signals at different temperatures, and the results are shown in fig. 5 and 7. Indicating that the SPR signal is affected by temperature to some extent, the MZI signal is sensitive to temperature; the concentration of the cholesterol solution was changed to obtain MZI signal and SPR signal at different concentrations of the cholesterol solution, and the results are shown in fig. 6 and 8. Indicating that the SPR signal is sensitive to RI and the MZI signal is insensitive to RI.
Since LSPR signals have a higher sensitivity to RI, but are cross-sensitive to RI and temperature; the MZI signal is insensitive to RI but sensitive to temperature. Therefore, a sensitivity matrix (1) for simultaneously detecting the two parameters is proposed, which solves the problem of temperature disturbance of the sensor based on RI variation, and performs temperature compensation by using the different characteristics of the two signals.
(1)
Wherein,and->Respectively represent->Spectral sum->Wavelength shift of spectrum, < >>And->Respectively replaceThe amounts of change of RI and T detected by the table, < >>And->RI sensitivity representing MZI and LSPR signals respectively, -, respectively>And->Representing the temperature sensitivity of the MZI and LSPR signals, respectively.
Thirdly, providing a spectral curve (4-PSCR) correction algorithm model based on four parameters, extracting parameters of the required LSPR signal obtained in the step S2, and fitting the LSPR signal with high precision;
in order to accurately identify the resonance wavelength, first, excitation light is scanned in a light source spectrum range of 550 to 750nm at a wavelength interval of 0.5nm, so that densely sampled spectrum data in a wider scanning range is obtainedWherein%) Represents the light intensity at a specific wavelength (+)>). Then, based on->Obtaining 17-order generalized polynomial fitting by a least square method,
…………………………………………………(2)
to better monitor the variation of LSPR signal wavelength, while maintaining faster speeds, also ensure that there is precision water with a polynomial fit similar to 17 th orderFlat by four linear transformation parametersIs defined by the variant form of (a)Is used as a storage function of the (c),
……………………………………(3)
wherein a predefined transformation matrix is setIts initial value is +.>Wherein->、/>Is the transverse and longitudinal stretch coefficient, ">、/>Is the transverse and longitudinal translation coefficient. After defining the above-mentioned storage function, measurements are made in the resonance region of 600-700 nm; if the sample is changed, a new spectrum is obtained>WhereinIs->New intensity at the site, and initially +.>A change occurs. Then, instead of performing 17-order curve fitting, based on equation (3), a Levenberg-Marquardt method is employed to solve the transformation matrix D and obtain an updated fitted curve +.>And its resonant wavelength.
The measured value is used to determine, for each of the measured values,the deviation from its fit value is expressed as,
…………………………………………………(4)
the sum of squares of the errors is noted as
…………………………………………………(5)
Thus, in the following steps, the goal is to find an optimized transformation matrix by an optimized iterative processSo thatAnd->Infinitesimal, and the steps are as follows:
step 1: setting an initial value，/>,/>Wherein->Is to adjust the damping factor of the iteration, +.>Is an iteration threshold.
Step 2: according to the Levenberg-Marquardt method we define
………………………………………(6)
Wherein the method comprises the steps ofIs an identity matrix>Is->Is represented by the following formula:
…………………………………………………(7)
step 3: finding final values for resonant wavelength calculation
If it isOr the number of iterations reaches a certain value, i.e. 200, the iteration is terminated and the value +.>。
If it isThe damping factor is set to +.>And returns to step 2.
If it isThe damping factor is set to +.>And returns to step 2.
After the iteration is terminated, a final transformation matrix is obtained. In order to obtain an accurate resonance wavelength +.>In natural boundary conditions for->Interpolation with cubic spline is then possible +.>Obtaining resonance wavelength +.>。
Note that the same calculation is performed in each pixel position, so that a two-dimensional resonance wavelength gray value image can be constructed. The algorithm only requires the use of a few data points to extract the resonant wavelength while maintaining a high level of accuracy similar to the higher order polynomial fit. Theoretically, four data points are needed to get a result due to the presence of four unknown variables; here, 10 data points are selected to further suppress noise levels and meet dynamic detection range requirements.
To visualize this process, FIG. 10 shows an example based on analog data, in whichIs an initial fit of the closely sampled SPR spectral profile over a broad spectral range with refractive index n=1.33, whereas +.>Is a sparse sampled spectral data point in the range 600-700 nm at a sample refractive index n=1.35. By means of->Translation and stretching of the four parameters H ', L', X ', Y' of the model can obtain a fitting curve while maintaining the fitting precision level of a high-order polynomial>。
And fourthly, processing the LSPR signals extracted from the resonance trough signals to obtain the wavelength shift of the LSPR signals so as to reversely push out the concentration of the cholesterol solution.
In the description of the present specification, the descriptions of the terms "one embodiment," "example," "specific example," and the like, mean that a particular feature, structure, material, or characteristic described in connection with the embodiment or example is included in at least one embodiment or example of the present invention. In this specification, schematic representations of the above terms do not necessarily refer to the same embodiments or examples. Furthermore, the particular features, structures, materials, or characteristics described may be combined in any suitable manner in any one or more embodiments or examples.
The foregoing has shown and described the basic principles, principal features and advantages of the invention. It will be understood by those skilled in the art that the present invention is not limited to the embodiments described above, and that the above embodiments and descriptions are merely illustrative of the principles of the present invention, and various changes and modifications may be made without departing from the spirit and scope of the invention, which is defined in the appended claims.
Claims (7)
1. The preparation method of the tapered optical fiber sensor for detecting the concentration of cholesterol based on the MZI-LSPR is characterized by comprising the following steps:
s1, removing a coating layer of a single-mode fiber, and then carrying out fusion drawing to ensure that the diameters of a cladding layer and a fiber core of the fiber are gradually reduced along the axial direction of the fiber to form a tapered fiber with the waist diameter smaller than 20 um;
s2, dissolving gold chloride in deionized water, boiling under reflux, adding sodium citrate under stirring, reacting the solution until the color changes from pale yellow to dark red, and filtering to obtain AuNPs;
s3, plating an Au film on the surface of the tapered optical fiber waist, immersing the tapered optical fiber waist in a DTT solution for modification, and then immersing in an AuNPs solution for modification;
s4, soaking the tapered optical fiber waist modified by AuNPs in a mixed solution of PMBA and MEA for modification;
s5, soaking the tapered optical fiber waist modified by PMBA molecules in beta-CD solution, and then washing the PMBA molecules which are not combined on the tapered optical fiber surface by deionized water to prepare the tapered optical fiber sensor.
2. The method for manufacturing a tapered optical fiber sensor for detecting cholesterol concentration based on MZI-LSPR of claim 1, wherein in S2, the particle size of the AuNPs manufactured is 48nm.
3. The method for manufacturing the tapered optical fiber sensor for detecting cholesterol concentration based on the MZI-LSPR according to claim 1, wherein in S3, a magnetron sputtering coating machine is used to coat an Au film on the waist surface of the tapered optical fiber.
4. The method for manufacturing a tapered optical fiber sensor for detecting cholesterol concentration based on MZI-LSPR according to claim 1, wherein in S4, PMBA concentration is 5mM and MEA concentration is 10mM.
5. The method for preparing the tapered optical fiber sensor for detecting cholesterol concentration based on MZI-LSPR according to claim 1, wherein the concentration of beta-CD solution is 0.01M and the PH value is 7.8.
6. A tapered optical fiber sensor for detecting cholesterol concentration based on MZI-LSPR, characterized by being prepared using the preparation method of any one of claims 1 to 5.
7. A method for measuring cholesterol concentration using a tapered fiber sensor for measuring cholesterol concentration based on MZI-LSPR as defined in claim 6, comprising the steps of:
step one, connecting a spectrometer with a conical optical fiber sensor, immersing a sensing area of the conical optical fiber sensor into cholesterol solution, and under the action of a light source, reading a resonance trough by the spectrometer and transmitting the resonance trough to a computer; and by continuously increasing the concentration of the cholesterol solution, a plurality of resonance trough signals are obtained and reserved;
performing Fourier transform on the monitored resonance trough, extracting a LSPR signal after the transformation, and then performing inverse Fourier transform on the LSPR signal to obtain a required LSPR signal;
step three, performing parameter extraction on the LSPR signal obtained in the step two by utilizing a spectral curve correction algorithm based on four parameters, and fitting the LSPR signal with high precision;
and fourthly, analyzing and processing the LSPR signals extracted from the resonance trough signals to obtain the wavelength shift of the LSPR signals so as to reversely deduce the concentration of the cholesterol solution.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202410009087.2A CN117538294B (en) | 2024-01-04 | 2024-01-04 | Conical optical fiber sensor for detecting cholesterol concentration based on MZI-LSPR and preparation method |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202410009087.2A CN117538294B (en) | 2024-01-04 | 2024-01-04 | Conical optical fiber sensor for detecting cholesterol concentration based on MZI-LSPR and preparation method |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN117538294A CN117538294A (en) | 2024-02-09 |
| CN117538294B true CN117538294B (en) | 2024-03-26 |
Family
ID=89788387
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202410009087.2A Active CN117538294B (en) | 2024-01-04 | 2024-01-04 | Conical optical fiber sensor for detecting cholesterol concentration based on MZI-LSPR and preparation method |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN117538294B (en) |
Citations (12)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101505653A (en) * | 2006-08-15 | 2009-08-12 | 佛罗里达大学研究基金会有限公司 | Condensate glucose analyzer |
| KR20130001886A (en) * | 2011-06-28 | 2013-01-07 | 고려대학교 산학협력단 | Localized surface plasmon resonance sensor of gold nonorod with improving sensitivity, method of preparing the same and method of detecting bioproduct using the same |
| CN103913802A (en) * | 2014-02-27 | 2014-07-09 | 北京航天时代光电科技有限公司 | Manufacturing method of multimode optical fiber coupler based on single mode light source |
| CN107255633A (en) * | 2017-05-03 | 2017-10-17 | 上海大学 | The polymerization phenyl boric acid film conical fiber saccharide sensor device and its manufacture method resonated based on metal surface plasma |
| CN107525589A (en) * | 2017-08-25 | 2017-12-29 | 上海交通大学 | A kind of wavelength scaling system and method |
| CN108225602A (en) * | 2017-12-26 | 2018-06-29 | 北京信息科技大学 | The interference-type full-fiber sensor that temperature strain based on FP-MZ structures measures simultaneously |
| CN109540179A (en) * | 2018-12-21 | 2019-03-29 | 南京信息工程大学 | Optical fiber taper sensing probe based on surface plasma body resonant vibration and preparation method thereof |
| WO2019126735A1 (en) * | 2017-12-21 | 2019-06-27 | Georgia Tech Research Corporation | Methods and systems for improved collection of interstitial fluid |
| CN110726697A (en) * | 2019-10-12 | 2020-01-24 | 华南师范大学 | Mach-Zehnder interferometer optical fiber ammonia gas sensor based on tapered fine core optical fiber |
| CN111272730A (en) * | 2020-02-11 | 2020-06-12 | 南京信息工程大学 | High-sensitivity optical fiber surface plasmon sensor and preparation method thereof |
| CN111829991A (en) * | 2020-08-04 | 2020-10-27 | 东北大学 | beta-CD-based reflective optical fiber cholesterol sensor and preparation method thereof |
| CN212391394U (en) * | 2020-08-04 | 2021-01-22 | 东北大学 | beta-CD-based reflective optical fiber cholesterol sensor |
Family Cites Families (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US8953159B2 (en) * | 2008-10-03 | 2015-02-10 | The Board Of Trustees Of The University Of Illinois | Surface enhanced raman spectroscopy nanodome biosensors and methods of manufacturing the same |
-
2024
- 2024-01-04 CN CN202410009087.2A patent/CN117538294B/en active Active
Patent Citations (12)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101505653A (en) * | 2006-08-15 | 2009-08-12 | 佛罗里达大学研究基金会有限公司 | Condensate glucose analyzer |
| KR20130001886A (en) * | 2011-06-28 | 2013-01-07 | 고려대학교 산학협력단 | Localized surface plasmon resonance sensor of gold nonorod with improving sensitivity, method of preparing the same and method of detecting bioproduct using the same |
| CN103913802A (en) * | 2014-02-27 | 2014-07-09 | 北京航天时代光电科技有限公司 | Manufacturing method of multimode optical fiber coupler based on single mode light source |
| CN107255633A (en) * | 2017-05-03 | 2017-10-17 | 上海大学 | The polymerization phenyl boric acid film conical fiber saccharide sensor device and its manufacture method resonated based on metal surface plasma |
| CN107525589A (en) * | 2017-08-25 | 2017-12-29 | 上海交通大学 | A kind of wavelength scaling system and method |
| WO2019126735A1 (en) * | 2017-12-21 | 2019-06-27 | Georgia Tech Research Corporation | Methods and systems for improved collection of interstitial fluid |
| CN108225602A (en) * | 2017-12-26 | 2018-06-29 | 北京信息科技大学 | The interference-type full-fiber sensor that temperature strain based on FP-MZ structures measures simultaneously |
| CN109540179A (en) * | 2018-12-21 | 2019-03-29 | 南京信息工程大学 | Optical fiber taper sensing probe based on surface plasma body resonant vibration and preparation method thereof |
| CN110726697A (en) * | 2019-10-12 | 2020-01-24 | 华南师范大学 | Mach-Zehnder interferometer optical fiber ammonia gas sensor based on tapered fine core optical fiber |
| CN111272730A (en) * | 2020-02-11 | 2020-06-12 | 南京信息工程大学 | High-sensitivity optical fiber surface plasmon sensor and preparation method thereof |
| CN111829991A (en) * | 2020-08-04 | 2020-10-27 | 东北大学 | beta-CD-based reflective optical fiber cholesterol sensor and preparation method thereof |
| CN212391394U (en) * | 2020-08-04 | 2021-01-22 | 东北大学 | beta-CD-based reflective optical fiber cholesterol sensor |
Non-Patent Citations (2)
| Title |
|---|
| LSPR- and SPR-Based Fiber-Optic Cholesterol Sensor Using Immobilization of Cholesterol Oxidase Over Silver Nanoparticles Coated Graphene Oxide Nanosheets;Semwal, V 等;IEEE SENSORS JOURNAL;20120201;第18卷(第3期);1039-1046 * |
| LSPR-based cholesterol biosensor using a tapered optical fiber structure;Kumar, S 等;BIOMEDICAL OPTICS EXPRESS;20190501;第10卷(第5期);第2150-2160页 * |
Also Published As
| Publication number | Publication date |
|---|---|
| CN117538294A (en) | 2024-02-09 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| Yang et al. | Development of glucose sensor using gold nanoparticles and glucose-oxidase functionalized tapered fiber structure | |
| Li et al. | Convex fiber-tapered seven core fiber-convex fiber (CTC) structure-based biosensor for creatinine detection in aquaculture | |
| Niu et al. | Sensitivity enhanced D-type large-core fiber SPR sensor based on Gold nanoparticle/Au film co-modification | |
| Yu et al. | A novel optical fiber glucose biosensor based on carbon quantum dots-glucose oxidase/cellulose acetate complex sensitive film | |
| Tu et al. | Optimization of gold-nanoparticle-based optical fibre surface plasmon resonance (SPR)-based sensors | |
| Zhong et al. | Three-layer-structure polymer optical fiber with a rough inter-layer surface as a highly sensitive evanescent wave sensor | |
| Zheng et al. | A plug-and-play optical fiber SPR sensor for simultaneous measurement of glucose and cholesterol concentrations | |
| Gong et al. | Highly sensitive SERS detection and quantification of sialic acid on single cell using photonic-crystal fiber with gold nanoparticles | |
| Kumar et al. | Development of uric acid biosensor using gold nanoparticles and graphene oxide functionalized micro-ball fiber sensor probe | |
| Zhu et al. | Tapered optical fiber-based LSPR biosensor for ascorbic acid detection | |
| Pathak et al. | Fabrication and characterization of TiO2 coated cone shaped nano-fiber pH sensor | |
| CN105158213A (en) | Device and method for detecting glucose based on optical fiber surface plasma resonance | |
| Wang et al. | pM level and large dynamic range glucose detection based on a sandwich type plasmonic fiber sensor | |
| Wang et al. | Cardiac troponin I detection using gold/cerium-oxide nanoparticles assisted hetro-core fiber structure | |
| Pandey et al. | Packaged negative axicon optical fiber probe and Bessel beam interferometry for refractive index measurement of hazardous liquid samples | |
| Li et al. | Gold/zinc oxide nanoparticles functionalized tapered SMF-MMF-SMF-based sensor probe for uric acid detection | |
| Chauhan et al. | Fiber optic pH sensor using TiO2-SiO2 composite layer with a temperature cross-sensitivity feature | |
| Liu et al. | WaveFlex Biosensor-using Novel Tri-Tapered in Tapered Four-Core Fiber with Multimode Fiber Coupling for Detection of Aflatoxin B1 | |
| Du et al. | Highly sensitive fiber optic enhanced Raman scattering sensor | |
| Singh et al. | WaveFlex Biosensor: MXene-Immobilized W-shaped Fiber-Based LSPR sensor for highly selective tyramine detection | |
| CN117538294B (en) | Conical optical fiber sensor for detecting cholesterol concentration based on MZI-LSPR and preparation method | |
| Ren et al. | A High-FOM surface plasmon resonance sensor based on MMF-TUMMF-MMF structure of optical fiber | |
| Uniyal et al. | Sensitive detection of vitamin C using etched SMS based LSPR biosensor | |
| CN112461794B (en) | Long-range SPR sensor and preparation method thereof | |
| Chen et al. | fM-level detection of glucose using a grating based sensor enhanced with graphene oxide |
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 |