CN117030667B - Multifunctional optical sensor and preparation method thereof - Google Patents

Abstract

The present disclosure provides a multifunctional optical sensor and a preparation method thereof. Specifically, the multifunctional optical sensor comprises: a substrate; and a plurality of functional films arranged at intervals on the substrate; wherein the plurality of functional films can detect at least two of pH, O ₂ and CO ₂ under the excitation light of the same wavelength. The plurality of functional films are arranged at intervals on the substrate so that the plurality of functional films can detect at least two of pH, O ₂ and CO ₂ under the excitation light of the same wavelength, thereby realizing parallel detection of multiple parameters and improving detection efficiency.

Description

Multifunctional optical sensor and preparation method thereof

Technical Field

The present disclosure relates to the field of detection technology, and in particular to a multifunctional optical sensor and a preparation method thereof.

Background technique

The pH, _CO2 and _O2 levels in the blood and tissues of organisms reflect the basic conditions of human respiration and metabolism, are closely related to life activities and disease diagnosis, and are extremely important parameters in clinical medicine and basic research. In addition, in the fields of food safety and environmental engineering, there is also a great demand for the monitoring of pH, _O2 and _CO2 in food and the environment.

Summary of the invention

In view of this, an object of the present disclosure is to provide a multifunctional optical sensor and a method for preparing the same.

Based on the above objectives, in a first aspect, an embodiment of the present disclosure provides a multifunctional optical sensor, including:

a substrate; and

A plurality of functional films are arranged on the substrate at intervals; wherein the plurality of functional films can detect at least two of pH, O ₂ and CO ₂ under excitation light of the same wavelength.

In a second aspect, an embodiment of the present disclosure provides a method for preparing a multifunctional optical sensor, the method comprising:

providing a substrate;

A plurality of functional films are formed on the substrate at intervals; wherein the plurality of functional films can detect at least two of pH, O ₂ and CO ₂ under excitation light of the same wavelength.

As can be seen from the above, the multifunctional optical sensor and the preparation method thereof provided by the present disclosure arrange a plurality of functional films at intervals on a substrate, so that the plurality of functional films can detect at least two of pH, O ₂ and CO ₂ under excitation light of the same wavelength, thereby realizing parallel detection of multiple parameters and improving detection efficiency.

BRIEF DESCRIPTION OF THE DRAWINGS

In order to more clearly illustrate the technical solutions in the present disclosure or related technologies, the drawings required for use in the embodiments or related technical descriptions will be briefly introduced below. Obviously, the drawings described below are only embodiments of the present disclosure. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

FIG1A is a schematic diagram showing the structure of a multifunctional optical sensor provided by an embodiment of the present disclosure;

FIG1B is a schematic diagram showing the structure of another multifunctional optical sensor provided by an embodiment of the present disclosure;

FIG2 shows an excitation emission spectrum of a fluorescent probe provided by an embodiment of the present disclosure;

FIG3A shows a scanning electron image of a pH functional film on the inner wall of a capillary;

FIG3B shows a scanning electron image of the _O2 functional film on the inner wall of the capillary;

FIG3C shows the scanning electron image of the CO ₂ functional film on the inner wall of the capillary;

FIG4 shows the fluorescence emission spectra of a multifunctional optical sensor provided by an embodiment of the present disclosure under different pH environments;

FIG5 shows the fluorescence emission spectra of a multifunctional optical sensor provided by an embodiment of the present disclosure at different O ₂ concentrations;

FIG6 shows the fluorescence emission spectra of a multifunctional optical sensor provided by an embodiment of the present disclosure at different CO ₂ concentrations;

FIG. 7 illustrates the photostability of a multifunctional optical sensor provided by an embodiment of the present disclosure.

Detailed ways

In order to make the objectives, technical solutions and advantages of the present disclosure more clearly understood, the present disclosure is further described in detail below in combination with specific embodiments and with reference to the accompanying drawings.

It should be noted that, unless otherwise defined, the technical terms or scientific terms used in the embodiments of the present disclosure should be understood by people with ordinary skills in the field to which the present disclosure belongs. The "first", "second" and similar words used in the embodiments of the present disclosure do not indicate any order, quantity or importance, but are only used to distinguish different components. The terms "containing" or "including (comprising)" can be open, semi-enclosed and closed. In other words, the terms also include "essentially consisting of..." or "consisting of..." "Connected" or "connected" and similar words are not limited to physical or mechanical connections, but can include electrical connections, whether direct or indirect.

When terms such as "on", "above", "below", and "beside" are used to describe the positional relationship between two components, one or more components may be located between the two components unless these terms are used together with the terms "immediately" or "directly". When an element or layer is disposed "on" another element or layer, another layer or element may be directly inserted on the other element or between them. Even if not explicitly stated, the components are interpreted as including a normal error range.

Abbreviations used in the disclosed embodiments have their conventional meanings in the chemical and biological arts.Chemical structures and formulae set forth herein are constructed according to standardized valence rules known in the chemical arts.

In order to facilitate understanding of the technical solutions of the present disclosure, some technical terms involved in the present disclosure are introduced below.

pH functional film refers to a film for detecting pH; _CO2 functional film refers to a film for detecting _CO2 ; _O2 functional film refers to a film for detecting _O2 .

HPTS refers to 8-hydroxypyrene-1,3,6-trisulfonate; Ru(dpp) ₃ (PF ₆ ) ₂ refers to tris(4,7-phenyl-1,10-phenanthroline)ruthenium(II) bis(hexafluorophosphate); Ru(bpy) ₂ (phen-NH ₂ )(PF ₆ ) ₂ is bis(2,2-bipyridine)-(aminophenanthroline) bis(hexafluorophosphate)ruthenium.

Unless otherwise specified, "M" in this article refers to "mol/L" and "mM" refers to "mmol/L".

Bioassay technology based on optical analysis is often used in monitoring pH, O ₂ , and CO ₂ due to its advantages such as fast response speed, high spatial resolution, and simple operation. Optical sensors are usually composed of optical probes and matrix materials, and the detection of the object to be detected is achieved by analyzing the specific optical signal changes after the optical probe interacts with the object to be detected.

Currently, a variety of optical sensors are designed for pH, O ₂ or CO ₂ monitoring, but there are few reports on sensors that can simultaneously detect multiple of pH, O ₂ and CO ₂ , and the detection efficiency is low.

In view of this, an embodiment of the present disclosure provides a multifunctional optical sensor, in which a plurality of functional films are spaced apart on a substrate, so that the plurality of functional films can detect at least two of pH, O ₂ and CO ₂ under excitation light of the same wavelength, thereby realizing parallel detection of multiple parameters and improving detection efficiency.

Fig. 1A is a schematic diagram showing the structure of a multifunctional optical sensor provided by an embodiment of the present disclosure. Fig. 1B is a schematic diagram showing the structure of another multifunctional optical sensor provided by an embodiment of the present disclosure.

Specifically, the multifunctional optical sensor includes:

a substrate 101; and

A plurality of functional films 102 are disposed at intervals on the substrate 101; wherein the plurality of functional films 102 can detect at least two of pH, O ₂ and CO ₂ under the excitation light of the same wavelength.

By arranging a plurality of functional films 102 at intervals, the interaction between different indicators can be effectively avoided, and the thickness of the functional films arranged separately is small, which helps to improve the sensitivity.

Optionally, the wavelength of the excitation light may be 450-500 nm, such as 460 nm, 470 nm, 485 nm or 500 nm.

In some embodiments, the substrate 101 may be a capillary (as shown in FIG. 1B ). The multifunctional films are fixed to different positions of the inner wall of the same capillary, and the capillary phenomenon of the capillary is utilized to realize the flow of liquid in the capillary without external force and contact multiple functional films, so that one capillary can transmit multiple signals at the same time, and multiple parameters (such as pH, O ₂ and CO ₂ ) can be monitored simultaneously with high efficiency and accuracy. In addition, by using the capillary as the substrate, only a small amount of the liquid to be tested is required to meet the detection requirements, and the liquid to be tested can be directly collected by the capillary, saving other auxiliary sampling equipment, helping to reduce the detection cost and improve the convenience of detection.

Furthermore, the length of the capillary is 4.5 to 6.0 cm, for example, 4.5 cm, 4.8 cm, 5.0 cm, 5.2 cm or 5.5 cm; the outer diameter is 2.8 to 3.2 mm, for example, 2.8 mm, 3.0 mm or 3.2 mm; the tube wall thickness is 0.8 to 1.2 mm, for example, 0.8 mm, 0.9 mm, 1.0 mm or 1.2 mm.

Optionally, the capillary tube has a length of 5 cm, an outer diameter of 3.0 mm, and a tube wall thickness of 2.0 mm.

In some alternative embodiments, the substrate may also be a glass plate or a quartz plate (as shown in FIG. 1A ).

In some embodiments, the functional film includes a fluorescent probe and a matrix. Here, the matrix allows the object to be detected to pass through and contact the fluorescent probe fixed (eg, coated) in the matrix, thereby realizing the detection of the object to be detected.

Furthermore, the matrix is selected from silane polymer, air-permeable and water-blocking polymer or (2-methacryloyloxyethyl phosphorylcholine) polymer.

Further, the fluorescent probe is selected from 8-hydroxypyrene-1,3,6-trisulfonate or ruthenium complex. Among them, 8-hydroxypyrene-1,3,6-trisulfonate can specifically detect pH and CO _2. Ruthenium complex can specifically detect O _2. Exemplarily, the ruthenium complex is selected from Ru(dpp) ₃ (PF ₆ ) ₂ , Ru(bpy) ₂ (phen-NH ₂ )(PF ₆ ) ₂ .

In some embodiments, the plurality of functional films include at least one of a pH functional film 1021 and a CO ₂ functional film 1023 ; wherein the fluorescent probes of the pH functional film 1021 and the CO ₂ functional film 1023 are the same and the matrices are different.

Exemplarily, the fluorescent probe can be 8-hydroxypyrene-1,3,6-trisulfonate; the matrix of the pH functional film can pass protons to detect pH, and the matrix of the _CO2 functional film can pass gas but not protons to reduce the effect of protons on _CO2 detection.

It should be noted that the detection of pH is to detect H ⁺ , ^{which exists in the solution. To avoid the influence of H+ on} _CO2 detection, the matrix of the _CO2 functional film adopts a breathable and water-blocking polymer, which can effectively avoid the influence of H ⁺ on _CO2 detection and improve the accuracy of _CO2 detection, such as a breathable and water-blocking silane polymer. The matrix of the pH functional film can adopt a silane polymer. Optionally, the silane polymer includes a silane hybrid polymer.

In some embodiments, the plurality of functional films further include an O ₂ functional film 1022 , and the O ₂ functional film 1022 is located between the pH functional film 1021 and the CO ₂ functional film 1023 .

Using the _O2 functional film 1022 to increase the distance between the pH functional film 1021 and the _CO2 functional film 1023 helps to reduce interference between the two and improve the accuracy of detection.

The present disclosure also provides a method for preparing a multifunctional optical sensor. The method comprises:

A substrate is provided; here, the substrate can be a capillary, a glass plate, a quartz plate, etc.

A plurality of functional films are formed on the substrate at intervals; wherein the plurality of functional films can detect at least two of pH, O ₂ and CO ₂ under excitation light of the same wavelength.

Here, the plurality of functional films detect at least two of pH, O ₂ and CO ₂ respectively.

Further, forming a plurality of functional films at intervals on the substrate includes forming at least two of a pH functional film, a CO ₂ functional film and an O ₂ functional film.

Optionally, the fluorescent probe of the pH functional film is 8-hydroxypyrene-1,3,6-trisulfonate. Optionally, the fluorescent probe of the _CO2 functional film is 8-hydroxypyrene-1,3,6-trisulfonate. Optionally, the fluorescent probe of the _O2 functional film is a ruthenium complex.

In some embodiments, the step of forming the pH functional film comprises:

(a1) Hexadecyltrimethylammonium bromide and 8-hydroxypyrene-1,3,6-trisulfonate are used to form an ion pair precipitate, which is then dried and dissolved in an alcohol solution.

Wherein, the molar ratio of hexadecyltrimethylammonium bromide to HPTS is 2:1.

Wherein, the alcohol solution is selected from ethanol.

Exemplarily, 0.76 mmol of hexadecyltrimethylammonium bromide (CTAB) is dissolved in 25 ml of deionized water at 45-55° C. to synthesize an ion pair; then, 0.38 mmol of HPTS is dissolved in 25 ml of deionized water and added to the CTAB solution, and the ion pair precipitate (HPTS-IP) is filtered, dried in an oven, and dissolved in ethanol.

(a2) Ethyltriethoxysilane (ETEOS), hydrochloric acid, and ethanol are mixed at a first molar ratio to obtain a first sol. Here, the hydrochloric acid is a 0.1 M hydrochloric acid aqueous solution.

Optionally, the first molar ratio is 1:0.007:6.25.

(a3) (3-glycidyloxypropyl)trimethoxysilane (GPTMS), 1-methylimidazole (MI), water and ethanol are mixed at a second molar ratio to obtain a second sol.

Optionally, the water is deionized water. Optionally, the second molar ratio is 1:0.69:4:6.25.

(a4) After mixing the first sol and the second sol in an equimolar ratio, diluting the alcohol solution, applying the mixture on the first region of the substrate, and forming a film under a first heating condition.

Optionally, the dilution factor may be 0.8×10 ² -1.1×10 ⁴ .

Optionally, the first heating condition is heating at 130-150° C. for 3.5-4.5 hours.

In some embodiments, the step of forming the _O2 functional film includes:

(b1) Preparation of a polymer of 2-methacryloyloxyethyl phosphorylcholine (MPC) and n-butyl methacrylate (BMA).

Exemplarily, 0.6 g of MPC and 0.015 g of azobisisobutyronitrile are dissolved in 2.6 mL of BMA, stirred and mixed in 20 mL of anhydrous ethanol, an inert gas (such as nitrogen or argon) is introduced to remove oxygen, and refluxed at a constant temperature of 68 to 72 ° C for 7.5 to 8.5 hours; after the reaction is completed, it is cooled to room temperature, and 10 times the volume of precipitant ether is introduced to precipitate 1.4 g of a white precipitate, i.e., a polymer.

(b2) dissolving the ruthenium complex and the polymer in tetrahydrofuran (THF), coating the second region of the substrate, and forming a film in the dark. Here, the film forming in the dark can be drying overnight in the dark at room temperature.

Optionally, the concentration of the polymer dissolved in tetrahydrofuran is 0.9-1.1 g/mL, for example 1 g/mL. Exemplarily, 1.4 g is dissolved in 1.4 mL of THF.

Optionally, the concentration of the ruthenium complex dissolved in tetrahydrofuran is 0.09-0.11 mg/mL, such as 0.10 mg/mL. Exemplarily, 1 mg of the ruthenium complex (such as Ru(dpp) ₃ (PF ₆ ) ₂ ) is dissolved in 10 mL of THF.

The THF solution of the ruthenium complex and the THF solution of the polymer are mixed and coated in a volume ratio of 1:1 to 1:2.

In some embodiments, the step of forming the _CO2 functional film comprises:

(c1) Tetra-n-octylammonium bromide is dissolved in ethyltriethoxysilane, and dichloromethane is added dropwise to obtain a first solution.

Optionally, 1-1.2 mmol of tetra-n-octylammonium bromide is dissolved in 9-11 g of ethyltriethoxysilane, and the amount of dichloromethane added is 2-4 drops.

For example, 1.1 mmol of tetra-n-octylammonium bromide is dissolved in 10 g of ethyltriethoxysilane, and 3 drops of dichloromethane are added.

(c2) dissolving 8-hydroxypyrene-1,3,6-trisulfonate in a NaOH solution to obtain a second solution; mixing the first solution and the second solution, extracting the organic phase, adding hydrochloric acid and stirring to obtain a third solution.

Here, the concentration of the NaOH solution is 0.9 to 1.1 mol/L, for example, 1 mol/L. The molar ratio of HPTS to NaOH is 0.03:2 to 0.04:2. For example, 0.08 g of NaOH is dissolved in 20 mL of deionized water to obtain a NaOH solution, and 0.038 mmol of HPTS is added.

Here, the mixing may be performed by shaking for 8 to 12 minutes and then allowed to stand for 8 to 12 minutes.

The extractant may be water, such as deionized water.

The pH of hydrochloric acid is 1.9 to 2.1, for example 2. Hydrochloric acid can neutralize NaOH.

The stirring time after adding hydrochloric acid can be 0.5 to 1.5 hours, for example, 0.5 hours, 0.8 hours, 1.0 hours, 1.2 hours, etc.

(c3) dissolving tetra-n-octylammonium bromide and silver oxide in an alcohol solution, stirring, taking out the supernatant and adding it to the third solution, fully dissolving it, coating it on the third area of the substrate, and forming a film under the second heating condition.

Optionally, tetra-n-octylammonium bromide and silver oxide are dissolved in methanol in equal moles, and the stirring time can be 3.5 to 4.5 hours. Optionally, the supernatant can be stored in a low temperature (eg, 4° C.) environment for later use.

Optionally, the second heating condition is heating at 65-75° C. for 8-10 hours.

In order to make the technical solution of the present disclosure clearer and easier to understand, the multifunctional optical sensor and the preparation method thereof provided by the present disclosure are described in detail below in conjunction with the accompanying drawings and specific embodiments.

Unless otherwise specified, the experimental methods used in the following examples are all conventional methods, and are performed according to the techniques or conditions described in the literature in the field or according to the product instructions.

Unless otherwise specified, the materials and reagents used in the following examples can be obtained from commercial sources.

Example 1

The structure of the multifunctional optical sensor of this embodiment is shown in FIG1B . The substrate of the optical sensor is a capillary tube, and the multifunctional film includes a pH functional film, an O ₂ functional film, and a CO ₂ functional film. The preparation methods of each film are as follows:

(a) The pH functional film uses HPTS as a fluorescent probe and is coated on the inner wall of the capillary by a sol-gel method, specifically comprising:

First, the HPTS-IP ion pair was synthesized by dissolving 0.76 mmol of hexadecyltrimethylammonium bromide (CTAB) in 25 ml of deionized water at 50°C. Then, 0.38 mmol of HPTS was dissolved in 25 ml of deionized water and added to the CTAB solution. Subsequently, the ion pair precipitate (HPTS-IP) was filtered, dried in an oven, and dissolved in ethanol.

Preparation of ethyltriethoxysilane (ETEOS)-based sol: ETEOS, 0.1 M hydrochloric acid aqueous solution and ethanol were mixed in a molar ratio of 1:0.007:6.25 to obtain a first sol;

Preparation of a sol based on (3-glycidyloxypropyl)trimethoxysilane (GPTMS): using GPTMS, 1-methylimidazole (MI), deionized water and ethanol as raw materials, a second sol is prepared in a molar ratio of 1:0.69:4:6.25;

Finally, the two sols were mixed in an equal molar ratio, and HPTS-IP was diluted 10 ³ times, applied to the capillary, and heated at 140°C for 4 hours.

(b) O ₂ functional film uses Ru(dpp) ₃ (PF6) ₂ fluorescent probe, first prepares 2-methacryloyloxyethyl phosphorylcholine (MPC)-butyl methacrylate (BMA) polymer membrane with ion exchange and ion permeation properties and dissolves it in tetrahydrofuran (THF), then dissolves Ru(dpp) ₃ (PF ₆ ) ₂ fluorescent probe therein and dries it on the inner wall of the capillary, specifically comprising:

First, 0.6 g of MPC and 0.015 g of azobisisobutyronitrile were dissolved in 2.6 mL of BMA, stirred and mixed in 20 mL of anhydrous ethanol, nitrogen or argon was introduced to remove oxygen, and refluxed at 70°C for 8 hours; after the reaction was completed, the solution was cooled to room temperature, and 10 times the volume of precipitant ether was introduced to precipitate 1.4 g of white precipitate;

Then, the precipitate was dissolved in tetrahydrofuran for later use; 1 mg of Ru(dpp) ₃ (PF ₆ ) ₂ was dissolved in 10 mL of tetrahydrofuran, and 1 mL of the solution was taken and mixed with the tetrahydrofuran solution of MPC-BMA polymer;

Finally, the mixed solution was applied to the middle of the capillary and left to dry overnight at room temperature away from light.

(c) The _CO2 functional film uses HPTS fluorescent probe, but the prepared sol-gel film has the characteristics of being permeable to air but not to protons, which can be distinguished from the pH film, including:

First, 1.1 mmol of tetra-n-octylammonium bromide was dissolved in 10 g of ethyltriethoxysilane, and 3 drops of dichloromethane were added dropwise to obtain a first solution;

Next, 0.08 g of NaOH was dissolved in 20 mL of deionized water, and 0.038 mmol of HPTS was added. The solution was mixed with the solution obtained in the previous step, shaken for 10 minutes, and then allowed to stand for 10 minutes. The organic phase of the mixed solution was extracted to obtain a light yellow liquid. 0.16 mL of dilute hydrochloric acid with a pH of 2.0 was added to the liquid, and stirred for 1 hour.

Then, 2.5 mmol of tetra-n-octylammonium bromide and 2.5 mmol of silver oxide were dissolved in 10 mL of methanol at the same time. After stirring for 4 hours, the supernatant was taken and stored in a 4°C environment. Then, 0.08 mL of the obtained solution was added to the solution obtained in the second step, shaken until fully dissolved, and sealed at 4°C.

Finally, the above solution was applied to the other end of the capillary and heated at 70° C. for 8 to 10 hours to obtain an optical multifunctional capillary sensor.

Example 2

The difference between this example and Example 1 is that in step (a), HPTS-IP is diluted 10 ² times.

Example 3

The difference between this example and Example 1 is that in step (a), HPTS-IP is diluted 10 ⁴ times.

Next, the capillary optical sensor prepared in Example 1 was used as a sample to study the physicochemical properties of the sample.

The spectral characterization was measured by a spectrometer model F4600 produced by Hitachi. The sample cell used for spectral characterization was a quartz cuvette with a size of 1.0 cm×1.0 cm and transparent on four sides.

FIG2 shows the excitation emission spectrum of the fluorescent probe provided in the embodiment of the present disclosure. Wherein, ex represents the excitation wavelength, and em represents the emission wavelength. The excitation spectrum results of the sample show that the HPTS fluorescent probe and the Ru(dpp) ₃ (PF ₆ ) ₂ fluorescent probe in the film have a strong excitation peak at around 460nm, proving that the HPTS molecules and the Ru(dpp) ₃ (PF ₆ ) ₂ molecules are effectively doped in the functional film and can be excited by a single excitation light of 460nm.

Figure 3A shows the scanning electron image of the pH functional film on the inner wall of the capillary; Figure 3B shows the scanning electron image of the O ₂ functional film on the inner wall of the capillary; Figure 3C shows the scanning electron image of the CO ₂ functional film on the inner wall of the capillary. It can be seen from Figures 3A to 3C that the pH functional film, the O ₂ functional film and the CO ₂ functional film have different microstructures, proving that Example 1 prepared a variety of functional films.

pH, CO ₂ , O ₂ sensitive characteristics

Buffer solutions with different pH values (5.8, 6.2, 6.6, 7.0, 7.4 and 7.8) were passed into the capillary sensor. After the two were fully reacted for 5 minutes, the emission spectra of the capillary optical sensor with different pH buffer solutions were characterized by a fluorescence spectrometer with an excitation wavelength of 460 nm and a monitoring wavelength of 480-600 nm. The results are shown in FIG4 .

As can be seen from Figure 4, the luminescence intensity changes with the pH value. When the pH value increases from 5.8 to 6.6, the HPTS luminescence intensity gradually increases with the increase of pH value; when the pH value increases from 6.6 to 7, the luminescence intensity increases rapidly with the increase of pH value; when the pH value increases from 7 to 7.8, the increase of luminescence intensity slows down.

Buffer solutions with different N ₂ -O ₂ concentrations were passed into the capillary optical sensor. After the two were fully reacted for 8 minutes, the capillary emission spectra of the buffer solutions with different N ₂ -O ₂ concentrations were characterized by a fluorescence spectrometer. The excitation wavelength was 460 nm and the monitoring wavelength was 540-690 nm. The results are shown in FIG5 .

It can be seen from Figure 5 that the luminescence intensity changes with the change of N ₂ -O ₂ concentration. As the O ₂ concentration increases, the emission intensity of Ru(dpp) ₃ (PF ₆ ) ₂ gradually decreases, and the O ₂ functional film shows a high sensitivity to the O ₂ concentration.

Buffer solutions with different N ₂ -CO ₂ concentrations were passed into the capillary optical sensor. After the two were fully reacted for 8 minutes, the capillary emission spectra of the buffer solutions with different N ₂ -CO ₂ concentrations were characterized by a fluorescence spectrometer. The excitation wavelength was 460 nm and the monitoring wavelength was 470-600 nm. The results are shown in Figure 6.

It can be seen from Figure 6 that the luminescence intensity changes with the change of N ₂ -CO ₂ concentration. As the CO ₂ concentration continues to increase, the HPTS fluorescence signal gradually weakens, and the CO ₂ functional film shows a high sensitivity to CO ₂ .

In summary, the capillary optical sensor provided by the embodiments of the present disclosure exhibits high pH, O ₂ and CO ₂ sensitivity and resolution.

stability

The photostability of the capillary optical sensor was measured by F4600 spectrometer, and the luminescence intensity of the same capillary optical sensor stored in dry and dark conditions was continuously monitored for 20 days, and the results are shown in Figure 7. The emission light intensity of the pH, O ₂ and CO ₂ functional films did not change significantly during the detection period, indicating that the matrix of the functional film layer has a good protective effect on the fluorescent probe and the capillary optical sensor has good photostability.

In summary, the multifunctional optical sensor provided in the embodiments of the present disclosure, through three different polymer films coating the fluorescent probe ruthenium complex (Ru(dpp) ₃ (PF ₆ ) ₂ ) sensitive to O ₂ and 8-hydroxypyrene-1,3,6-trisulfonate (HPTS) sensitive to pH and CO ₂ , can use a single wavelength excitation light to simultaneously measure the concentrations of pH, CO ₂ , and O ₂ based on the changes in fluorescence signals in each detection area, thereby achieving sensitive and accurate monitoring of the pH, CO ₂ and O ₂ levels in the solution with high detection efficiency.

The multifunctional optical sensor provided by the embodiments of the present disclosure has good stability and reversibility, has outstanding advantages in applications in the fields of pH, _O2 and _CO2 detection, as well as related disease diagnosis and treatment and environmental monitoring, and shows good application prospects.

In addition, the multifunctional optical sensor has a simple and flexible preparation method and is inexpensive.

Those skilled in the art will appreciate that the multifunctional optical sensors prepared in other embodiments have similar effects, which will not be described in detail.

Those skilled in the art should understand that the discussion of any of the above embodiments is merely illustrative and is not intended to imply that the scope of the present disclosure (including the claims) is limited to these examples. Based on the concept of the present disclosure, the technical features in the above embodiments or different embodiments may be combined, the steps may be implemented in any order, and there are many other variations of the different aspects of the embodiments of the present disclosure as described above, which are not provided in detail for the sake of simplicity.

While the disclosure has been described in conjunction with specific embodiments thereof, many alternatives, modifications and variations of these embodiments will be apparent to those skilled in the art in light of the foregoing description.

The embodiments of the present disclosure are intended to cover all such substitutions, modifications and variations that fall within the broad scope of the appended claims. Therefore, any omissions, modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the embodiments of the present disclosure should be included in the scope of protection of the present disclosure.

Claims (10)

1. A multifunctional optical sensor, comprising: a substrate; and A plurality of functional films are arranged on the substrate at intervals; wherein the plurality of functional films can detect pH, O ₂ and CO ₂ under the excitation light of the same wavelength; wherein, The functional film comprises a fluorescent probe and a matrix; wherein the matrix of the functional film for detecting _O2 comprises a polymer of 2-methacryloyloxyethyl phosphorylcholine and n-butyl methacrylate. 2 . The optical sensor according to claim 1 , wherein the substrate is selected from a capillary, a glass sheet or a quartz sheet. 3. The optical sensor according to claim 2 is characterized in that the length of the capillary is 4.5~6.0 cm, the outer diameter is 2.8~3.2 mm, and the wall thickness is 0.8~1.2 mm. 4. The optical sensor according to claim 1, characterized in that the fluorescent probe of the functional film for detecting _O2 is a ruthenium complex. 5. The optical sensor according to claim 1, characterized in that the multiple functional films include a pH functional film and a CO ₂ functional film; wherein the fluorescent probes of the pH functional film and the CO ₂ functional film are the same and the matrices are different. 6. The optical sensor according to claim 5, characterized in that the fluorescent probes of the pH functional film and the _CO2 functional film are 8-hydroxypyrene-1,3,6-trisulfonate; and/or The matrix of the pH functional film is a silane polymer; the matrix of the _CO2 functional film is a breathable and water-blocking polymer. 7. The optical sensor according to claim 1, characterized in that the multiple functional films include a pH functional film, a _CO2 functional film and an _O2 functional film, and the _O2 functional film is located between the pH functional film and the _CO2 functional film. 8. A method for preparing a multifunctional optical sensor, characterized in that the preparation method comprises: providing a substrate; A pH functional film, a CO ₂ functional film and an O ₂ functional film are formed on the substrate at intervals; wherein the pH functional film, the CO ₂ functional film and the O ₂ functional film include fluorescent probes and a matrix, and can detect pH, O ₂ and CO ₂ under the excitation light of the same wavelength; wherein, The steps of forming the _O2 functional film include: Take 2-methacryloyloxyethyl phosphorylcholine and azobisisobutyronitrile in proportion and dissolve them in n-butyl methacrylate, stir and mix them evenly in anhydrous ethanol, introduce nitrogen or argon to remove oxygen, and reflux at a constant temperature; after the reaction is completed, cool the solution to room temperature, introduce ether as a precipitant, and precipitate to obtain a polymer of 2-methacryloyloxyethyl phosphorylcholine and n-butyl methacrylate; The ruthenium complex and the polymer are dissolved in tetrahydrofuran respectively, and then the tetrahydrofuran solutions of the two are mixed according to a preset amount and then coated on the second area of the substrate to form a film in the dark. 9. The preparation method according to claim 8, characterized in that: The step of forming the pH functional film comprises: Using hexadecyltrimethylammonium bromide and 8-hydroxypyrene-1,3,6-trisulfonate to form an ion pair precipitate, which is then dried and dissolved in an alcohol solution; Mixing ethyltriethoxysilane, hydrochloric acid, and ethanol in a first molar ratio to obtain a first sol; Mixing (3-glycidyloxypropyl)trimethoxysilane, 1-methylimidazole, water and ethanol in a second molar ratio to obtain a second sol; The alcohol solution is diluted after mixing the first sol and the second sol in an equal molar ratio, and coated on the first area of the substrate to form a film under a first heating condition; The steps of forming the _CO2 functional film include: Dissolving tetra-n-octylammonium bromide in ethyltriethoxysilane, and adding dichloromethane dropwise to obtain a first solution; Dissolving 8-hydroxypyrene-1,3,6-trisulfonate in a NaOH solution to obtain a second solution; mixing the first solution and the second solution, extracting an organic phase, adding hydrochloric acid and stirring to obtain a third solution; Tetra-n-octylammonium bromide and silver oxide are dissolved in an alcohol solution, stirred, and the supernatant is added to the third solution, fully dissolved, coated on the third area of the substrate, and formed into a film under the second heating condition. 10. The preparation method according to claim 9, characterized in that the first heating condition is heating at 130-150° C. for 3.5-4.5 hours; and/or The second heating condition is heating at 65-75° C. for 8-10 hours.