CN115112634A - Optical fiber biosensor and detection system - Google Patents

Abstract

An optical fiber biosensor and detection system, the optical fiber biosensor including a transmission optical fiber and a metal sensing film having an array of nanopores disposed thereon, the metal sensing film configured to receive incident light from the transmission optical fiber and reflect the incident light into the transmission optical fiber for detection. The optical fiber biosensor has the advantages of compactness, portability and the like.

Description

Optical fiber biosensor and detection system

Technical Field

The embodiment of the disclosure relates to an optical fiber biosensor and a detection system.

Background

Surface Plasmon Resonance (SPR) technology is widely used in the field of biology, and can detect the interaction between various biomolecules and obtain comprehensive detailed information of the biomolecules. The information data can provide great help for research in the fields of pharmacy, drug discovery, antibody screening, protein structure function, gene analysis, drug optimization, quality control and the like, and can also quickly detect biomarker molecules, so that the method is used for early diagnosis of diseases such as various cancers, myocardial infarction and the like. The detection device based on the technology is difficult to be popularized comprehensively due to the complex structure.

Disclosure of Invention

At least one embodiment of the present disclosure provides an optical fiber biosensor, including a transmission optical fiber and a metal sensing film, where a nanopore array is disposed on the metal sensing film, and the metal sensing film is configured to receive incident light from the transmission optical fiber and reflect the incident light into the transmission optical fiber for detection.

In some examples, the metal sensing film includes a middle sensing portion for sensing and an edge portion, and the middle sensing portion is disposed in suspension.

In some examples, the optical fiber biosensor further comprises a membrane fixing part for fixing the metal sensing membrane; the middle sensing part is positioned on the end face of the membrane fixing part, and the edge part is bent to the side face of the membrane fixing part and is fixed.

In some examples, the edge portion of the metal sensing membrane includes a plurality of sub-portions that are split from each other.

In some examples, the metal sensing film is spaced apart from the transmission optical fiber, and the metal sensing film is near the surface of the transmission optical fiber for contacting with a sample to be detected.

In some examples, the optical fiber biosensor further comprises an optical fiber fixing part for fixing the transmission optical fiber, a membrane fixing part for fixing the metal sensing membrane, and a sleeve for fixing the optical fiber fixing part and the membrane fixing part; and the sleeve is provided with a transmission channel, and the transmission channel is used for transmitting the sample to be detected to the surface of the metal sensing film close to the transmission optical fiber.

In some examples, the optical fiber biosensor further comprises a hollow column disposed at an end of the transmission optical fiber, and the metal sensing film is disposed at an end face of the hollow column away from the transmission optical fiber.

In some examples, the optical fiber biosensor further comprises a hollow optical fiber, one end of the hollow optical fiber is welded with the transmission optical fiber, and the end face of the other end of the hollow optical fiber is provided with the metal sensing film.

In some examples, the optical fiber biosensor further comprises an optical fiber fixing part for fixing the transmission optical fiber, and the metal sensing film is fixed at one end of the optical fiber fixing part and spaced apart from the transmission optical fiber.

At least one embodiment of the present disclosure further provides a detection system, including any one of the above optical fiber biosensor, a light source, an optical fiber coupler, and a spectrometer, where the optical fiber coupler is configured to transmit light emitted from the light source to the transmission optical fiber, and to transmit reflected light from the transmission optical fiber to the spectrometer.

Drawings

In order to more clearly illustrate the technical solutions of the embodiments of the present disclosure, the drawings of the embodiments will be briefly described below. It is to be understood that the drawings in the following description are directed to only some embodiments of the disclosure and are not limiting of the disclosure.

FIGS. 1A-1B are several schematic diagrams of a fiber optic biosensor;

FIGS. 2A-2C, 3A-3D, and 4A-4B are schematic illustrations of fiber optic biosensors provided in some embodiments of the present disclosure;

fig. 4C is a schematic view of a metal sensing film provided in at least one embodiment of the present disclosure; and

fig. 5 and 6A-6C are schematic diagrams of detection systems provided by some embodiments of the present disclosure.

Detailed Description

The present disclosure, however, is not limited to the details of construction and arrangements of parts illustrated in the drawings and detailed description, since various modifications and changes will become apparent to those skilled in the art upon reading the following description and drawings. It should be noted that the features illustrated in the drawings are not necessarily drawn to scale. The present disclosure omits descriptions of well-known materials, components, and process techniques so as not to obscure the example embodiments of the present disclosure. The examples given are intended merely to facilitate an understanding of ways in which the example embodiments of the disclosure may be practiced and to further enable those of skill in the art to practice the example embodiments. Thus, these examples should not be construed as limiting the scope of the embodiments of the disclosure.

Unless otherwise defined, technical or scientific terms used herein shall have the ordinary meaning as understood by one of ordinary skill in the art to which this disclosure belongs. The use of "first," "second," and similar terms in this disclosure is not intended to indicate any order, quantity, or importance, but rather is used to distinguish one element from another. The word "comprising" or "comprises", and the like, means that the element or item listed before the word covers the element or item listed after the word and its equivalents, but does not exclude other elements or items. "upper", "lower", "left", "right", and the like are used merely to indicate relative positional relationships, and when the absolute position of the object being described is changed, the relative positional relationships may also be changed accordingly.

Unless defined otherwise, the terms "mounted," "connected," and "connected" are to be construed broadly, e.g., as meaning a fixed connection, a removable connection, or an integral connection; can be mechanically or electrically connected; they may be connected directly or indirectly through intervening media, or they may be interconnected between two elements. The specific meaning of the above terms in the present application can be understood by those of ordinary skill in the art as appropriate.

Without conflict, the embodiments of the present disclosure and features of the embodiments may be combined with each other to create new embodiments.

Surface plasmon resonance is a physical optical phenomenon that occurs when a light beam couples with a metal thin film through a dielectric surface. In 1902, Wood discovered this phenomenon for the first time in optical experiments. When light enters the surface of the metal film, if the frequency of the light is consistent with the frequency of free electrons (namely plasma) oscillated by the metal surface, the incident light is coupled into surface plasma, and at the angle, the transmission rate or the reflection rate is obviously reduced due to the obvious absorption of the incident light beam caused by the surface plasma resonance, and an absorption peak is necessarily presented in an emergent spectrum.

Plasma can be excited on the metal surface by a beam of white light, and then the transmitted light or reflected light of the white light on the metal film loses one color (wavelength), i.e., an absorption peak is generated. If a small amount of foreign matter adheres to the surface of the metal film, the lost color (absorption peak wavelength) shifts as the amount of foreign matter increases. The micro color change is detected to sensitively sense the micro content of foreign matters in the environment, and the chemical molecule detection with high sensitivity and low detection limit is realized.

For example, an antibody for detecting a cancer marker molecule may be modified on the surface of the metal film in advance, and when the metal film is placed in a solution containing the cancer marker molecule, the cancer marker molecule will bind to the antibody, and any other substance in the solution will not bind to the antibody. By measuring the color shift of the lost incident light relative to the color of the marker molecule prior to binding to the antibody and comparing it to a calibrated value, the concentration of the cancer marker molecule can be determined, thereby predicting whether the cancer is at an early or late stage. By monitoring the specific binding between the molecules, a plurality of other disease markers can be detected, and great help can be provided for research in the fields of drug discovery, antibody screening, protein structure function, gene analysis, drug optimization, quality control and the like.

The excitation of the light surface plasma can adopt optical fiber transmission light excitation, the metal sensing film can be integrated on the end face of the optical fiber, and the wavelength position of the absorption peak of the surface plasma and the deviation of the absorption peak along with the environmental change are tested by collecting the spectrum of the transmission light, so that the environmental change is sensed.

Compared with a transmission type detection structure for detecting transmitted light, the reflection type detection structure for detecting reflected light only needs to arrange a light transmission system (such as a transmission optical fiber) on one side of the metal film, and the single optical fiber simultaneously realizes the excitation and the collection of signals, so that the overall structural design is more concise and flexible, and the rapid detection and analysis in situ on site can be realized. For example, transmission sensors still require a fluid delivery system, while end-reflection sensors can measure the fluid in a cuvette with a fiber-optic sensing probe without the fluid delivery system.

A surface plasma resonance sensor based on SPR adopts a continuous metal film as a metal sensing film, and has very strict requirements on the oblique incidence angle of a light beam in a free space in order to obtain stronger optical coupling and higher detection signal-to-noise ratio, so that the instrument is complex to assemble, large in size and high in price.

FIGS. 1A-1B are schematic diagrams of several reflective surface plasmon resonance detectors using continuous metal sensing films, respectively.

As shown in fig. 1A, the sensor uses a prism to realize an accurate incident angle, so that the whole device has a complex structure, a large volume and a high cost, and the wider application of the sensor is limited.

The volume of the sensor can be greatly reduced by adopting the optical fiber as a light transmission medium, and the measured space is reduced to the order of the diameter size of the optical fiber, however, in order to realize a specific incident angle, a complex optical path or structural design is required. One method is to grind the end face of the optical fiber to form an angled bevel.

As shown in fig. 1B, the transmission fiber is a ring-core fiber, and includes a fiber core 1, a ring-core outer cladding 2, and a ring-core inner cladding 3, the fiber end is ground into a frustum with a designed angle and height to form an inclined plane 4 with a specific angle, and the metal sensing film is disposed on the inclined plane 4, so that the transmission light 6 can be incident on the metal sensing film at a predetermined incident angle. The structure has complex process, needs to grind the optical fiber, and has complex process and high cost.

At least one embodiment of the present disclosure provides a reflective fiber biosensor based on SPR, which employs a metal sensing film with a nanopore array, and when incident light passes through the metal sensing film with periodically repeated sub-wavelength small holes, local surface plasmons can be excited to generate strong coupled light; without strict requirements on the incident angle of the light. For example, the incident light may be incident perpendicularly or at a small oblique angle to the metal sensing film.

Because the angle of the incident light is not strictly required, the metal sensing film is more flexibly arranged relative to the transmission optical fiber, and the overall structure of the sensor is simpler, more compact and more portable. For example, portable on-site quick inspection can be achieved.

Fig. 2A is a schematic structural diagram of an optical fiber biosensor provided in at least one embodiment of the present disclosure, and as shown in fig. 2A, the optical fiber biosensor 20 includes a transmission optical fiber 21 and a metal sensing film 22, the metal sensing film 22 is provided with nano holes 220 arranged in an array, and the pore diameter of the nano holes 220 is in a sub-wavelength scale, for example, in a range of 50 nm to 500 nm. The metal sensing film 22 is configured to receive incident light from the transmission fiber and reflect the incident light into the transmission fiber for detection.

The present embodiment of the disclosure does not limit the kind and structure of the transmission fiber 21, and may be, for example, a multimode fiber or a single-mode fiber. For example, the transmission fiber 21 may be a multimode fiber with a larger cross-sectional area to increase the area of the sensor chip and improve the detection sensitivity thereof. As shown in fig. 2A, the transmission fiber 21 includes a core 210 and a cladding 211, and the refractive index of the core 210 is higher than that of the cladding 211.

For example, the material of the metal sensing film 22 includes a noble metal, which can generate a stronger optical surface plasmon. For example, the material of the metal sensor film 22 is gold (Au), silver (Ag), copper (Cu), or the like.

For example, the thickness of the metal sensing film 22 ranges from 50 nm to 200 nm, such as 50 nm to 100 nm, such as 50 nm, 80 nm, 100 nm.

For example, the surface of the metal sensor film 22 is disposed perpendicular to the axial direction of the transmission fiber. For example, the metal sensor film 22 is configured to receive incident light that is normally incident to its surface. When the metal sensing film 22 is close enough to the end face of the transmission fiber 21, most of the light emitted from the end face of the transmission fiber 21 can be regarded as being emitted along the axial direction, and the surface of the metal sensing film 22 is arranged perpendicular to the axial direction, so that the metal sensing film can obtain larger light energy and obtain stronger optical coupling, thereby improving the signal-to-noise ratio. However, this is not to be taken as a limitation of the present disclosure.

The first surface 221 of the metal sensing film 22 close to the transmission fiber 21 and the second surface 222 far from the transmission fiber 21 can be used as sensing detection surfaces to contact with a sample to be detected according to different example applications. For example, antibodies can be modified on the first surface 221 or the second surface 222 to bind to a disease marker to be detected for detection.

As shown in fig. 2A, the metal sensing film 22 is disposed at a distance from the transmission fiber 21, and the metal sensing film 22 is close to the first surface 221 of the transmission fiber 21 for contacting with the sample to be detected, i.e. the first surface 221 serves as a detection surface.

For example, the optical fiber biosensor 20 further includes a fiber fixing portion 25, and the fiber fixing portion 25 is used to protect and fix an end portion (an end portion near the metal sensing film) of the transmission optical fiber 21. The optical fiber fixing portion 25 has a hollow structure, and one end of the transmission optical fiber 21 is inserted and fixed therein. For example, the fiber fixing portion 25 is a fiber ferrule, such as a metal ferrule or a ceramic ferrule.

For example, the optical fiber biosensor 20 further includes a membrane fixing portion 24, and the membrane fixing portion 24 is used to fix the metal sensing membrane 22. The film fixing portion 24 is disposed perpendicularly opposite to the transmission optical fiber 21 in the axial direction of the optical fiber.

The specific structure of the film fixing portion 24 is not limited in the embodiments of the present disclosure, as long as the metal sensing film can be fixed. For example, the membrane holder 24 may be a fiber stub.

The metal sensor film 22 is adhered to the film fixing portion 24 by, for example, a glue (not shown). For example, the colloid may be an optical epoxy.

For example, the optical fiber biosensor further includes a sleeve 23 for fixing the fiber fixing part 25 and the film fixing part 24 of the transmission fiber 21, thereby fixing the transmission fiber 21 and the metal sensing film 22 at a predetermined relative position. As shown in fig. 2A, the ferrule 23 fixes the optical fiber fixing portion 25 and the film fixing portion 24 to each other.

The present disclosure is not limited to a specific structure of the sleeve 23. For example, the sleeve 23 is a hollow cylindrical body with both ends open, and the fiber fixing portion 25 to which the transmission fiber 21 is fixed and the film fixing portion 24 to which the metal sensor film 22 is fixed are inserted from both ends of the sleeve 23 and fixed to each other. For example, the wall of the sleeve 23 is provided with opposite openings to form a transmission channel 230, and the transmission channel 230 is used for transmitting the sample to be detected to the detection surface of the metal sensing film 22. As shown in fig. 2A, the transmission passage 230 opens at opposite sides of the portion of the sleeve 23 between the transmission fiber 21 and the metal sensing film 22. For example, two openings are oppositely disposed in the longitudinal direction (direction perpendicular to the optical axis of the optical fiber) to form the transmission channel.

When detecting, a sample to be detected (for example, a patient sample) flows in from the transmission channel 230 on one side of the sleeve 23, and contacts with the detection surface, i.e., the first surface 221 of the metal sensing film 22, i.e., is adsorbed by the antibody on the first surface 221. Light 7 is incident on the first surface 221 from the transmission fiber 21 and reflected back to the transmission fiber 21, and the patient sample can be detected by performing a spectral analysis on the reflected light.

For example, the metal sensor film 22 includes an edge portion and an intermediate sensor portion for sensing, which is a portion of the metal sensor film 22 that mainly interacts with light. For example, the range of the middle sensing part may be an orthogonal projection range of the core 210 of the transmission optical fiber 21 on the metal sensing film 22 along the axial direction or larger than the orthogonal projection range, for example, an orthogonal projection range of the optical fiber 21 on the metal sensing film 22 along the axial direction; for example, the central sensing section is a circular area with a radius twice the radius of the core 210, since the light has some divergence after leaving the transmission fiber.

In the optical fiber biosensor provided in at least some embodiments of the present disclosure, the middle sensing portion of the metal sensing film 22 is disposed in a floating manner, i.e., neither surface of the middle sensing portion is in contact with the supporting substrate. Thus, when incident light is incident on the metal sensor film 22, the light can be prevented from being affected by the attachment of the metal sensor film 22 on the detection surface and the opposite surface of the detection surface, and the detection surface of the metal sensor film 22 can excite stronger surface plasmon, thereby improving the detection sensitivity.

Fig. 2B is a schematic view of an optical fiber biosensor according to another embodiment of the present disclosure, which is different from the embodiment shown in fig. 2A mainly in that the membrane fixing portion 24 is a hollow column. The metal sensing film 22 is fixed to one end of the hollow pillar by an edge portion, so that the middle sensing portion 225 of the metal sensing film 22 is suspended.

Since the metal sensing film provided by the embodiment of the present disclosure has the nano-holes therein, the nano-holes are generally formed through an etching process, for example, the etching process uses semiconductor process equipment and is high in cost, and the etching process easily causes damage to the supporting substrate, and it is inconvenient to directly deposit the metal sensing film on the last supporting substrate (e.g., the end portion of the optical fiber, the end portion of the film fixing portion) and then perform etching. In some examples, the nanopore structure metal sensing membrane may be formed on an intermediate substrate and then transferred to a final support substrate. For example, the metal sensing membrane may be fixed to the final support substrate by glue transfer.

When the metal sensing film 22 is fixed on the hollow column by glue, the suspension arrangement can also avoid that the glue covers the middle sensing part 225 and even flows into the nano-holes of the middle sensing part 225, which results in inaccurate detection results.

In other examples, as shown in fig. 2C, in order to prevent the surface of the metal sensing film 22 from being damaged when the film fixing portion 24 to which the metal sensing film 22 is fixed is inserted into the sleeve 23 in the axial direction of the sleeve 23, a portion of the sleeve 23 corresponding to the film fixing portion 24 may be provided in a groove-like structure, and the wall of the sleeve 23 does not shield the metal sensing film 22, so that the film fixing portion 24 may be inserted into the sleeve from above in a direction perpendicular to the axial direction of the sleeve (i.e., in the longitudinal direction in the drawing) to be fixed without affecting the surface of the metal sensing film 22.

For example, referring to fig. 4A later, when the film fixing portion 24 is a hollow column, in order to avoid the adhesion failure due to the small adhesion area between the end surface of the hollow column and the metal sensing film 22, at least a part of the edge portion of the metal sensing film 22 is bent to the side surface of the hollow column and adhered to the side surface of the hollow column, and in this case, the metal sensing film 22 is easily detached by the pressing of the sleeve side wall when the film fixing portion 24 is inserted in the sleeve axial direction, and the longitudinal insertion is designed to effectively solve the problem.

In other embodiments, the surface of the metal sensing film 22 away from the transmission fiber, i.e., the second surface 222, is a detection surface for contacting a sample to be detected. In this case, the detection surface can be directly exposed to the outside for inserting the sample to be detected, without providing a liquid flow conveying system, so that the structure is more compact and portable.

As shown in fig. 3A, the metal sensor film 22 is provided on an end face of the transmission fiber 21, the end face being perpendicular to the axial direction of the transmission fiber 21. The second surface 222 of the metal sensing film 22 is exposed, and the fiber-optic detection probe is directly inserted into the sample 60 to be detected for detection.

In other examples, the optical fiber biosensor may further include a membrane fixing portion for fixing the metal sensing membrane, the membrane fixing portion and the transmission optical fiber being located on the same side of the metal sensing membrane, and a surface of the metal sensing membrane away from the transmission optical fiber being used for contacting with a sample to be detected.

For example, the middle sensor portion 225 of the metal sensor film 22 can be suspended by providing the film fixing portion with a hollow structure, thereby improving the sensitivity of detection.

Fig. 3B is a schematic diagram of a fiber optic biosensor according to further embodiments of the present disclosure. The main difference between this embodiment and the embodiment shown in fig. 3A is that the optical fiber biosensor 20 further includes a hollow optical fiber 26 (an example of a membrane fixing portion in the embodiment of the present disclosure), and a core portion of the hollow optical fiber 26 is empty. The hollow core optical fiber 26 is disposed coaxially with the transmission optical fiber 21. One end of the hollow optical fiber 26 is fusion-bonded to the transmission optical fiber 21, and the end face of the other end is provided with the metal sensing film 22.

For example, the core (hollow structure) of the hollow core fiber 25 may have the same radius as the transmission fiber 210. The light spots can be more concentrated by adopting the hollow optical fiber 25 to guide light, and the energy loss is reduced.

For example, the radius of the hollow structure of the hollow fiber 26 may be larger than the radius of the core 210 of the transmission fiber 21, so as to reduce the contact area between the hollow fiber and the metal sensing film 22 and avoid affecting the performance of the middle sensing portion of the metal sensing film.

For example, after the hollow optical fiber 26 and the transmission fiber 21 are fusion-spliced, they are put together in the fiber fixing portion 25, and then the metal sensing film 22 is disposed on the end face of the hollow optical fiber 26.

For example, as shown in fig. 3C, a hollow column 27 (another example of a membrane holder in the embodiment of the present disclosure) may be employed instead of the hollow optical fiber 26. The hollow post 27 is located at the end of the fiber fixing portion 25 of the transmission fiber 21, which are fixed to each other by the ferrule 23. The hollow column 27 has a short length and thus has less influence on light transmission.

The metal sensing diaphragm 22 is fixed to the end face of the hollow post 27. The inner diameter of the hollow column 27 can be designed according to actual needs. For example, the inner diameter of the hollow pillar 27 is larger than the inner diameter of the core 210 of the transmission fiber 21, for example, two times or more of the inner diameter of the core 210. For example, as shown in FIG. 3C, the inner diameter of the hollow post 27 is larger than the radius of the entire transmission fiber.

For example, this arrangement can prevent the colloid from flowing into the middle sensor portion 225 and even into the nanopores of the middle sensor portion 225 to affect the measurement sensitivity and accuracy.

In still other examples, as shown in fig. 3D, the metal sensing film 22 may also be directly disposed at the end of the optical fiber fixing portion 25, and its exposed surface serves as a detection surface, and a sample to be detected may be directly inserted during detection. For example, the transmission fiber 21 is fixed in the fiber fixing portion 25 and spaced apart from the metal sensing film 22, and a gap 250 is formed between the end surface of the transmission fiber 21 and the metal sensing film 22, so that the middle sensing portion of the metal sensing film is suspended.

In other examples, in order to further prevent the colloid from entering the middle sensing portion of the metal sensing film and affecting the detection sensitivity, the edge portion of the metal sensing film may be bent to the supporting substrate for fixing.

Fig. 4A-4B are schematic diagrams of optical fiber biosensors according to still other embodiments of the present disclosure, and the embodiment shown in fig. 4A is different from the embodiment shown in fig. 3C mainly in that at least a portion of the edge portion 223 of the metal sensing diaphragm 22 is bent to the side of the outer sleeve 23. As shown in fig. 4A, the middle sensing portion 225 of the metal sensing film 22 is located at the end surface of the hollow pillar 27, and the edge portion 223 of the metal sensing film 22 is bent to the side surface of the outer sleeve 23 and is adhered and fixed to the side surface by the glue 226, so as to avoid the weak adhesion caused by the small adhesion area between the end surface of the hollow pillar 27 and the metal sensing film 22.

In other examples, the glue 226 may only exist on the edge portion of the bent metal sensing film and not between the end surface of the hollow pillar 27 and the metal sensing film 22, so as to avoid the adverse effect of the glue on the detection.

For example, since the end surface of the hollow pillar 27 is not used for gluing, the end surface can be set smaller, that is, the wall thickness of the hollow pillar can be made smaller, so that the area of the suspended middle sensing portion 225 is larger, and the detection sensitivity is improved.

Similarly, the embodiment shown in FIG. 4B is different from the embodiment shown in FIG. 3D mainly in that at least part of the edge portion 223 of the metal sensing film is bent to the side of the fiber fixing portion 25. As shown in fig. 4B, the middle sensing portion 225 of the metal sensing film 22 is located at the end face of the optical fiber fixing portion 25, and the edge portion 223 of the metal sensing film 22 is bent to the side face of the optical fiber fixing portion 25 and is fixed to the side face by glue, that is, the glue only exists on the edge portion of the bent metal sensing film and does not exist between the end face of the optical fiber fixing portion 25 and the metal sensing film 22, so as to avoid the adverse effect of the glue on the detection.

For example, the metal sensing film 22 may be irregularly shaped in order to make the metal sensing film 22 better conform to the side surface of the sleeve or the film fixing portion. For example, the edge portion of the metal sensing film 22 includes a plurality of sub-portions extending from the intermediate sensing portion, and the plurality of sub-portions are separated from each other, that is, the plurality of sub-portions are not directly connected to each other, but are integrally connected to each other by being connected to the intermediate sensing portion.

Fig. 4C illustrates a schematic diagram of a metal sensing film 22 provided by at least one embodiment of the present disclosure. As shown, the metal sensing film 22 has a petal shape or a polygonal star shape, and includes a middle sensing portion 225 (indicated by a dotted circle) and an edge portion 223. For example, the intermediate sensor portion 225 is located at an end face of the film fixing portion 24. The edge portion 223 includes a plurality of sub-portions 223a, and each sub-portion 223a protrudes from the intermediate sensing portion 225 and is independently adhered to a side surface of the sleeve or the film fixing portion by a gel.

For example, as shown in FIG. 4C, the metal sensor film 22 can be obtained by ion beam cutting of the entire nanoporous metal film.

At least one embodiment of the present disclosure further provides a detection system, including the optical fiber biosensor provided in any of the above embodiments.

Fig. 5 is a schematic diagram of a detection system according to at least one embodiment of the present disclosure. As shown in fig. 5, the detection system 30 includes the fiber optic biosensor 20, a light source 31, a fiber optic coupler 32, and a spectrometer 33. The fiber coupler 32 is configured to transmit light emitted from the light source 31 to the optical transmission fiber 21 and to transmit light from the transmission fiber 21 to the spectrometer 33. The light source 31 is, for example, a Light Emitting Diode (LED). The light source 31 is, for example, a broadband illumination source, and the light source 31 is, for example, configured as a white light source. For example, the fiber coupler may be replaced with an optical circulator.

For example, the optical fiber coupler 32 has one end connected to the transmission fiber 21 of the optical fiber biosensor 20 and the other end connected to the light source 31 through an optical fiber, thereby receiving light from the light source 31. The fiber coupler 32 is also connected to a spectrometer 33 so as to transmit the incoming reflected light to the spectrometer 33.

For example, the detection system further comprises a signal processor 34 configured to receive the output signal of the spectrometer 33 and output a detection result.

Fig. 6A-6C illustrate several scenarios for application of the fiber optic biosensor 20 and the detection system 30 provided by some embodiments of the present disclosure.

For example, as shown in fig. 6A, the optical fiber biosensor 20 can be inserted into a sample 60 to be detected for rapid detection of pathogens.

For example, as shown in FIG. 6B, the fiber optic biosensor 20 can also be placed in a sample flow cell 36 for on-line detection.

For example, the fiber optic biosensor 20 can also be used repeatedly by rapidly restoring the detection activity by chemical methods, and as shown in fig. 6C, the biosensor 20 can be used for high-throughput scanning detection of a plurality of samples 37 (e.g., arranged in an array).

The above description is intended to be exemplary of the present disclosure, and not to limit the scope of the present disclosure, which is defined by the claims appended hereto.

Claims (10)

1. An optical fiber biosensor comprises a transmission optical fiber and a metal sensing film,

wherein the metal sensing film is provided with a nanopore array, and the metal sensing film is configured to receive incident light from the transmission optical fiber and reflect the incident light into the transmission optical fiber for detection.

2. The optical fiber biosensor of claim 1, wherein the metal sensing film comprises a middle sensing portion for sensing and an edge portion, the middle sensing portion being disposed in suspension.

3. The optical fiber biosensor of claim 2, further comprising a membrane fixing part, wherein the membrane fixing part is used to fix the metal sensing membrane;

the middle sensing part is positioned on the end face of the membrane fixing part, and the edge part is bent to the side face of the membrane fixing part and is fixed.

4. The optical fiber biosensor of claim 3, wherein the edge portion of the metal sensing film comprises a plurality of sub-portions, the plurality of sub-portions being split from each other.

5. The optical fiber biosensor according to claim 1, wherein the metal sensing film is disposed at a distance from the end surface of the transmission optical fiber, the metal sensing film being adjacent to the surface of the transmission optical fiber for contacting with a sample to be detected.

6. The optical fiber biosensor according to claim 5, further comprising an optical fiber fixing part, a membrane fixing part, and a sleeve,

the optical fiber fixing part is used for fixing the transmission optical fiber, the film fixing part is used for fixing the metal sensing film, and the sleeve is used for fixing the optical fiber fixing part and the film fixing part;

and the sleeve is provided with a transmission channel, and the transmission channel is used for transmitting the sample to be detected to the surface of the metal sensing film close to the transmission optical fiber.

7. The optical fiber biosensor according to claim 1, further comprising a hollow pillar,

the hollow column is arranged at the end part of the transmission optical fiber, and the metal sensing film is arranged on the end face, far away from the transmission optical fiber, of the hollow column.

8. The optical fiber biosensor according to claim 1, further comprising a hollow optical fiber, wherein one end of the hollow optical fiber is fusion-spliced with the transmission fiber, and the end face of the other end is provided with the metal sensing film.

9. The optical fiber biosensor according to claim 1, further comprising a fiber fixing part, wherein the fiber fixing part is used for fixing the transmission fiber, and the metal sensing film is fixed at one end of the fiber fixing part and spaced apart from the transmission fiber.

10. A detection system comprising a light source, a fiber coupler, a spectrometer, and the fiber optic biosensor of any of claims 1-9,

wherein the fiber coupler is configured to transmit light emitted by the light source to the transmission fiber and to transmit reflected light from the transmission fiber to the spectrometer.

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