Molecular carriers for molecular detection

Abstract

The present invention relates to a molecular carrier for molecular detection, which comprises: a substrate; an intermediate layer arranged on the surface of the substrate; a metal layer arranged on the surface of the intermediate layer away from the substrate; wherein the substrate is a flexible substrate; the intermediate layer comprises a substrate and a plurality of patterned protrusions arranged on the substrate; the metal layer is arranged on the surface of the patterned protrusions.

Description

Technical Field

[0001] The invention relates to a molecular carrier for molecular detection, a preparation method thereof and a method for detecting molecules using the carrier. Background Art

[0002] Single Molecule Detection (SMD) technology is an ultra-sensitive detection technology that can detect single molecules. It is widely used in chemical analysis, DNA sequencing, nanomaterial analysis, medical diagnosis, molecular dynamics mechanism, food safety and other fields. Compared with traditional analytical methods, single molecule detection studies the individual behavior of the system in a non-equilibrium state, or the fluctuation behavior in an equilibrium state. Therefore, it is particularly suitable for studying chemical and biochemical reaction dynamics, the interaction of biomolecules, structure and function information, early diagnosis of major diseases, pathological research and high-throughput drug screening.

[0003] At present, in single molecule detection technology, the test object of the sample to be detected is generally extracted and placed on a molecular carrier for detection, and the molecular carrier used in the detection is mostly a hard substrate. At the same time, the process of extracting the sample may cause damage to the sample structure, and the process of extracting the sample also makes the detection method cumbersome. Summary of the invention

[0004] In view of this, it is indeed necessary to provide a molecular carrier that will not destroy the sample to be tested.

[0005] A molecular carrier for molecular detection, comprising: a substrate; an intermediate layer, arranged on the surface of the substrate; a metal layer, arranged on the surface of the intermediate layer away from the substrate; wherein the substrate is a flexible substrate; the intermediate layer comprises a substrate and a plurality of patterned protrusions arranged on the substrate; the metal layer is arranged on the surface of the patterned protrusions.

[0006] Compared with the prior art, the molecular carrier of the present invention has the following beneficial effects: since the substrate in the molecular carrier adopts a flexible substrate, the flexible substrate can be well adhered to an irregular surface, therefore, the molecular carrier can perform molecular detection on an irregular surface and can realize in-situ detection on the surface of the object to be detected; the metal layer is arranged on a mesh structure formed by a plurality of convex strips, and under the excitation of the incident light, the metal surface plasma undergoes resonance absorption, and the convex strips of the network structure play a role in surface enhanced Raman scattering, which can improve the SERS (Surface enhanced Raman scattering) enhancement factor and enhance Raman scattering. BRIEF DESCRIPTION OF THE DRAWINGS

[0007] Figure 1 This is a schematic diagram of the structure of the molecular carrier provided in the first embodiment of the present invention.

[0008] Figure 2 This is a cross-sectional view of the molecular carrier provided by the first embodiment of the present invention along the II-II direction.

[0009] Figure 3 This is a flow chart of the method for preparing a molecular carrier provided in the first embodiment of the present invention.

[0010] Figure 4 for Figure 3 Cross-sectional view of the carbon nanotube composite structure along line IV-IV.

[0011] Figure 5 This is a scanning electron microscope photograph of the carbon nanotube film used in the first embodiment of the present invention.

[0012] Figure 6 This is a scanning electron microscope photograph of the non-twisted carbon nanotube wire used in the first embodiment of the present invention.

[0013] Figure 7 This is a scanning electron microscope photograph of the twisted carbon nanotube wire used in the first embodiment of the present invention.

[0014] Figure 8 This is a scanning electron microscope photograph of the carbon nanotube composite structure provided in the first embodiment of the present invention.

[0015] Fig. 9 This is a scanning electron microscope photograph of a single carbon nanotube coated with an aluminum oxide layer in the carbon nanotube composite structure provided in the first embodiment of the present invention.

[0016] Fig.10 This is a flow chart of the single molecule detection method provided in the first embodiment of the present invention.

[0017] Fig.11 The detector measures the spectra of different analyte concentrations from the front and back sides of the molecular carrier respectively.

[0018] Fig.12 This is a photo of the in-situ detection of crystal violet (CV) molecules on the surface of tomatoes using a Raman spectrometer.

[0019] Fig.13 This is the spectral detection result of in-situ detection of crystal violet (CV) molecules on the surface of tomatoes by Raman spectrometer.

[0020] Fig.14 This is the Raman spectrum detection result of 4-ATP molecules on the molecular carrier after wiping the apple surface with the molecular carrier.

[0021] Fig.15 This is a schematic diagram of the structure of a molecular carrier provided in the second embodiment of the present invention.

[0022] Fig.16 This is a flow chart of the method for preparing a molecular carrier provided in the second embodiment of the present invention.

[0023] Fig.17 This is a schematic diagram of the structure of a molecular carrier provided in the third embodiment of the present invention.

[0024] Fig.18 This is a flow chart of a method for preparing multiple molecular carriers provided in the third embodiment of the present invention.

[0025] Fig.19 This is a schematic structural diagram of a molecular detection device provided in the fourth embodiment of the present invention.

[0026] Fig. 20 Schematic diagram of the structure of using a metal frame to fix the molecular carrier.

[0027] Fig.21 A schematic diagram of the structures of multiple molecular carriers provided in the fourth embodiment of the present invention.

[0028] Main component symbols

[0029] Molecular carrier 10，20 Base 11 Middle Layer 12 Substrate 121 Patterned convex 122 Holes 124 Metal layer 13 Carbon nanotube composite structure 110 Carbon nanotube structure 112 Prefab Layer 114 Micropores 116 Samples to be tested 14 Analyte molecule 15 Fixing elements 16 Detector 17 Control computer 18

[0030] The following specific embodiments will further illustrate the present invention in conjunction with the above-mentioned drawings. DETAILED DESCRIPTION

[0031] The present invention will be further described in detail below in conjunction with specific embodiments and drawings.

[0032] Please also read Figure 1 to Figure 2 The first embodiment of the present invention provides a molecular carrier 10 for molecular detection, which includes a substrate 11, an intermediate layer 12 and a metal layer 13. Specifically, the intermediate layer 12 is arranged on the surface of the substrate 11, and the metal layer 13 is arranged on the surface of the intermediate layer 12. The intermediate layer 12 includes a substrate 121 and a plurality of patterned protrusions 122 arranged on the substrate 121, and the patterned protrusions 122 are arranged on the surface of the substrate 121 away from the substrate 11. The patterned protrusions 122 may include a plurality of convex strips arranged crosswise to form a mesh structure, thereby defining a plurality of holes 124. The intersection of the plurality of convex strips is an integral structure. The patterned protrusions 122 may also include a plurality of protrusions arranged in an array, and the grooves between the plurality of protrusions are crosswise distributed in a mesh.

[0033] The substrate 11 can be an insulating substrate or a semiconductor substrate. The substrate 11 is a flexible substrate, which can be placed on a curved surface and fit with the curved surface. Specifically, the material of the substrate 11 can be polyethylene terephthalate (PET), polyimide (PI), polymethyl methacrylate (PMMA), polydimethylsiloxane (PDMS), polyethylene naphthalate (PEN), etc. In the present embodiment, the material of the substrate 11 is polyethylene terephthalate. The shape, size and thickness of the substrate 11 are not limited and can be selected according to the actual molecular detection needs. In the present embodiment, the shape of the substrate is a flat plate.

[0034] The substrate 121 is arranged on the surface of the base 11. The shape of the substrate 121 is not limited, and it only needs to have two surfaces arranged opposite to each other. The size of the substrate 121 is not limited, and the thickness is 50 nanometers to 300 nanometers. Preferably, the thickness of the substrate 121 is 100 nanometers to 200 nanometers. When the thickness of the substrate 121 is too thin, such as less than 100 nanometers, the substrate 11 will interfere with or affect the spectrum in the subsequent trace molecule Raman detection process; when the thickness of the substrate 121 is too thick, such as greater than 200 nanometers, the overall flexibility of the molecular carrier 10 will be reduced. The substrate 121 and the patterned protrusion 122 can be an integral structure of the same material, or a multilayer structure of different materials. The substrate can be an insulating material such as silicon dioxide and silicon nitride, and a semiconductor material such as gallium nitride and gallium arsenide. In this embodiment, the substrate 121 and the patterned protrusion 122 are an integral structure formed by silicon dioxide. The patterned protrusion 122 is arranged on the surface of the substrate 121 away from the base 11. The present invention takes the patterned protrusion 122 as an example, and defines a part of the protrusion extending along the first direction as the first protrusion, and another part of the protrusion extending along the second direction as the second protrusion. The angle between the first direction and the second direction is greater than 0 degrees and less than or equal to 90 degrees, preferably, greater than or equal to 30 degrees. The multiple first protrusions are substantially parallel, and the multiple second protrusions are substantially parallel. The feature of the protrusions of the present invention being substantially parallel is determined by the feature that the extension direction of the carbon nanotubes in the carbon nanotube mask used in the preparation method thereof is substantially parallel. The length of each protrusion is unlimited, the width is 20 nanometers-150 nanometers, the height is 100 nanometers-500 nanometers, and the spacing between parallel and adjacent protrusions is 10 nanometers-300 nanometers. Therefore, the opening size of the hole 124 is 10 nanometers-300 nanometers, and the depth is 100 nanometers-500 nanometers. Preferably, the width of each protrusion is 50 nanometers-100 nanometers, the height is 200 nanometers-400 nanometers, and the spacing is 10 nanometers-50 nanometers. In this embodiment, the plurality of first convex strips are perpendicular to the plurality of second convex strips. The convex strips extend from one side to the other side of the substrate 121. The height of the convex strips is 300 nanometers.

[0035] The metal layer 13 is disposed on the surface of the patterned protrusion 122. Specifically, the metal layer 13 can be a continuous layered structure or a discontinuous layered structure. The metal layer 13 is disposed on the surface of the plurality of convex strips and in the holes 124 between the convex strips. The metal layer 13 can also be disposed only on the side walls of the plurality of convex strips and in the holes 124 between adjacent convex strips. The metal layer 13 can be a single-layer layered structure or a multi-layer layered structure. The metal layer 13 is substantially uniformly deposited on the surface of the convex strips and on the surface of the substrate 121 between the convex strips. A gap (Gap) is formed at the hole 124, where the surface of the metal layer 13 can generate surface plasma resonance, thereby generating Raman scattering enhancement. The thickness of the metal layer 13 is 2 nanometers to 200 nanometers, and preferably, the thickness of the metal layer 13 is uniform. The material of the metal layer 13 is not limited, and can be metals such as gold, silver, platinum, and copper. It can be understood that the material of the metal layer 13 is not limited to the above, and any metal material that is solid at room temperature can be used. In this embodiment, the metal layer 13 is gold with a thickness of 10 nanometers.

[0036] The molecular carrier provided by the present invention has the following advantages: since the substrate 11 in the molecular carrier 10 adopts a flexible substrate, the flexible substrate can be well adhered to an irregular surface, therefore, the molecular carrier 10 can perform molecular detection on an irregular surface and can realize in-situ detection on the surface of the object to be detected; the metal layer 13 is arranged on a mesh structure formed by a plurality of convex strips, and under the excitation of the incident light, the metal surface plasma undergoes resonance absorption, and the convex strips of the network structure play a role in surface enhanced Raman scattering, which can improve the SERS (Surface enhanced Raman scattering) enhancement factor and enhance Raman scattering.

[0037] Please also read Figure 3 and Figure 4 The first embodiment of the present invention provides a method for preparing the above-mentioned molecular carrier 10, which comprises the following steps:

[0038] Step S11, disposing an intermediate layer 12 on a substrate 11;

[0039] Step S12, providing a carbon nanotube composite structure 110 having a plurality of micropores 116, wherein the carbon nanotube composite structure 110 includes a carbon nanotube structure 112 and a prefabricated layer 114 coated on the surface of the carbon nanotube structure 112, and the carbon nanotube structure 112 includes a plurality of cross-arranged carbon nanotubes;

[0040] Step S13, disposing the carbon nanotube composite structure 110 on a surface 123 of the intermediate layer 12, so that the surface 123 of the intermediate layer 12 is partially exposed;

[0041] Step S14, using the carbon nanotube composite structure 110 as a mask to dry-etch the intermediate layer 12, thereby obtaining an intermediate layer 12 having a patterned protrusion 122, wherein the patterned protrusion 122 includes a plurality of cross-arranged protrusions;

[0042] Step S15, removing the carbon nanotube composite structure 110;

[0043] Step S16 , depositing a metal layer 13 on the surface of the patterned protrusion 122 .

[0044] In step S11, the intermediate layer 12 may be an insulating material such as silicon dioxide, silicon nitride, or a semiconductor material such as silicon, gallium nitride, or gallium arsenide. The intermediate layer 12 is directly disposed on the surface of the substrate 11. In this embodiment, the intermediate layer 12 is formed on the surface of the substrate 11 by plasma chemical vapor deposition. It is understood that the method of forming the intermediate layer 12 on the substrate 11 is not limited thereto, and any method that can dispose the intermediate layer 12 on the substrate 11 is acceptable.

[0045] In step S12, the carbon nanotube structure 112 includes a plurality of carbon nanotubes arranged in an orderly manner and arranged crosswise to form a plurality of micropores, and the prefabricated layer 114 is coated on the surface of the plurality of carbon nanotubes. Preferably, the prefabricated layer 114 is coated on the entire surface of each carbon nanotube. The plurality of carbon nanotubes are tightly connected by van der Waals forces so that the carbon nanotube structure 112 and the carbon nanotube composite structure 110 form a self-supporting structure. The so-called self-supporting structure means that the structure can maintain a specific film-like structure without a support. Therefore, the carbon nanotube composite structure 110 is self-supporting and can be partially suspended. The carbon nanotubes include one or more of single-walled carbon nanotubes, double-walled carbon nanotubes and multi-walled carbon nanotubes. The carbon nanotubes are parallel to the surface of the carbon nanotube structure 112. The diameter of the single-walled carbon nanotube is 0.5 nanometers to 10 nanometers, the diameter of the double-walled carbon nanotube is 1.0 nanometers to 15 nanometers, and the diameter of the multi-walled carbon nanotube is 1.5 nanometers to 50 nanometers. The length of the carbon nanotube is greater than 50 micrometers. Preferably, the length of the carbon nanotube is 200 micrometers to 900 micrometers.

[0046] The carbon nanotube structure 112 includes at least one carbon nanotube film, at least one carbon nanotube wire or a combination thereof. The carbon nanotube film includes a plurality of uniformly distributed carbon nanotubes. The plurality of carbon nanotubes in the carbon nanotube film extend in one direction, and the plurality of carbon nanotubes form a plurality of carbon nanotube bundles, and the extension direction of the carbon nanotubes is parallel to the surface of the carbon nanotube film. Specifically, the carbon nanotube film may include a carbon nanotube pulling film. The carbon nanotube wire may be a non-twisted carbon nanotube wire or a twisted carbon nanotube wire. When the carbon nanotube structure 112 includes a plurality of carbon nanotube wires, the plurality of carbon nanotube wires are parallel to each other and spaced apart and cross-arranged at a certain angle to form a layered carbon nanotube structure. The layered carbon nanotube structure includes a plurality of micropores, which are through holes that penetrate the thickness direction of the layered carbon nanotube structure. The size of the micropore is 1 nanometer to 0.5 micrometer.

[0047] See also Figure 5 Specifically, the carbon nanotube film includes a plurality of continuous and directional carbon nanotube bundles. The plurality of carbon nanotube bundles are connected end to end by van der Waals forces. Each carbon nanotube bundle includes a plurality of carbon nanotubes parallel to each other, and the plurality of carbon nanotubes parallel to each other are tightly bound by van der Waals forces. The diameter of the carbon nanotube bundle is 10 nanometers to 200 nanometers, preferably 10 nanometers to 100 nanometers. The carbon nanotubes in the carbon nanotube film are preferentially oriented and arranged in the same direction. The carbon nanotube film includes a plurality of micropores. The micropore is a through hole that runs through the thickness direction of the layered carbon nanotube structure. The micropore can be a pore and / or a gap. When the carbon nanotube structure 112 includes only a single-layer carbon nanotube film, there is a gap between adjacent carbon nanotube segments in the carbon nanotube film, wherein the size of the gap is 1 nanometer to 0.5 micrometer. It can be understood that in the carbon nanotube structure 112 composed of multiple layers of carbon nanotube film, the arrangement direction of the carbon nanotubes in two adjacent carbon nanotube films has an angle α, and 0°<α≤90°, so that the carbon nanotubes in the two adjacent layers of carbon nanotube film cross each other to form a network structure, and the network structure includes a plurality of pores, and the plurality of pores are evenly and regularly distributed in the carbon nanotube structure 112, wherein the pore diameter is 1 nanometer to 0.5 micrometer. The thickness of the carbon nanotube film is 0.01 micrometer to 100 micrometers. The carbon nanotube film can be directly obtained by drawing a carbon nanotube array. For the structure of the carbon nanotube film and its preparation method, please refer to the Chinese patent No. CN101239712B "Carbon Nanotube Film Structure and Preparation Method thereof" applied by Fan Shoushan et al. on February 9, 2007 and announced on May 26, 2010, applicants: Tsinghua University, Hongfujin Precision Industry (Shenzhen) Co., Ltd. To save space, it is only cited here, but all technical disclosures of the above application should also be regarded as part of the technical disclosures of the present application.

[0048] See also Figure 6 , the non-twisted carbon nanotube wire includes a plurality of carbon nanotubes arranged along the length direction of the non-twisted carbon nanotube wire. Specifically, the non-twisted carbon nanotube wire includes a plurality of carbon nanotube segments, the plurality of carbon nanotube segments are connected end to end by van der Waals force, and each carbon nanotube segment includes a plurality of carbon nanotubes that are parallel to each other and tightly bound by van der Waals force. The carbon nanotube segment has any length, thickness, uniformity and shape. The length of the non-twisted carbon nanotube wire is not limited, and the diameter is 0.5 nanometers to 100 micrometers. The non-twisted carbon nanotube wire is obtained by treating the carbon nanotube film with an organic solvent. Specifically, the organic solvent is soaked on the entire surface of the carbon nanotube film, and under the action of the surface tension generated when the volatile organic solvent evaporates, the plurality of carbon nanotubes that are parallel to each other in the carbon nanotube film are tightly bound by van der Waals force, so that the carbon nanotube film is shrunk into a non-twisted carbon nanotube wire. The organic solvent is a volatile organic solvent, such as ethanol, methanol, acetone, dichloroethane or chloroform, and ethanol is used in this embodiment. The non-twisted carbon nanotube wire treated with an organic solvent has a smaller specific surface area and lower viscosity than the carbon nanotube film not treated with an organic solvent.

[0049] The twisted carbon nanotube wire is obtained by twisting the two ends of the carbon nanotube film in opposite directions using a mechanical force. Figure 7 , the twisted carbon nanotube wire includes a plurality of carbon nanotubes spirally arranged around the axial direction of the twisted carbon nanotube wire. Specifically, the twisted carbon nanotube wire includes a plurality of carbon nanotube segments, the plurality of carbon nanotube segments are connected end to end by van der Waals force, and each carbon nanotube segment includes a plurality of carbon nanotubes parallel to each other and tightly bound by van der Waals force. The carbon nanotube segments have any length, thickness, uniformity and shape. The length of the twisted carbon nanotube wire is not limited, and the diameter is 0.5 nanometers to 100 micrometers. Further, the twisted carbon nanotube wire can be treated with a volatile organic solvent. Under the action of the surface tension generated when the volatile organic solvent evaporates, the adjacent carbon nanotubes in the twisted carbon nanotube wire after treatment are tightly bound by van der Waals force, so that the specific surface area of ​​the twisted carbon nanotube wire is reduced, and the density and strength are increased.

[0050] For the carbon nanotube linear structure and its preparation method, please refer to the Chinese patent application No. CN100411979C filed by Fan Shoushan et al. on September 16, 2002 and published on August 20, 2008, “A carbon nanotube rope and its manufacturing method”, applicants: Tsinghua University, Hongfujin Precision Industry (Shenzhen) Co., Ltd., and the Chinese patent application No. CN100500556C filed on December 16, 2005 and published on June 17, 2009, “Carbon nanotube filament and its manufacturing method”, applicants: Tsinghua University, Hongfujin Precision Industry (Shenzhen) Co., Ltd. In order to save space, only this is cited, but all technical disclosures of the above applications should also be regarded as part of the technical disclosures of the present invention.

[0051] In this embodiment, the carbon nanotube structure 112 is a two-layer vertically crossed carbon nanotube film, which is directly drawn from a grown carbon nanotube array. Multiple carbon nanotubes in the carbon nanotube structure 112 are connected end to end by van der Waals forces and arranged in the same direction.

[0052] The material of the prefabricated layer 114 may be at least one of metals such as gold, nickel, titanium, iron, aluminum, chromium, metal oxides such as aluminum oxide, magnesium oxide, zinc oxide, hafnium oxide, or metal sulfides. It is understood that the material of the prefabricated layer 114 is not limited to the above-mentioned materials, and may also be non-metallic oxides such as silicon dioxide, non-metallic carbides such as silicon carbide, or non-metallic nitrides such as silicon nitride, as long as they can be physically deposited on the surface of the carbon nanotube structure 112 and are not etched during the subsequent etching of the intermediate layer 12. The physical deposition means that the prefabricated layer 114 does not chemically react with the carbon nanotube structure 112, but is tightly combined with the carbon nanotube structure 112 through van der Waals forces and attached to the surface of the carbon nanotubes in the carbon nanotube structure 112. The thickness of the prefabricated layer 114 is not limited and may be 3 nanometers to 50 nanometers. In order to obtain nanometer-sized nanowire arrays and prevent the micropores in the carbon nanotube structure 112 from being excessively covered by the prefabricated layer 114, the thickness of the prefabricated layer 114 is preferably 3 nanometers to 20 nanometers. The micropores 116 of the carbon nanotube composite structure 110 have a smaller pore size than the micropores in the carbon nanotube structure 112.

[0053] The carbon nanotube composite structure 110 can be prepared by the following method: first, at least a portion of the carbon nanotube structure 112 is suspended in the air; then, a prefabricated layer 114 is deposited on the surface of the carbon nanotube structure 112 .

[0054] The carbon nanotube structure 112 has two opposite surfaces. The carbon nanotube structure 112 can be fixed by a frame, and the part located inside the frame is suspended, so that the carbon nanotube structure 112 is fully exposed, so as to facilitate the subsequent simultaneous formation of the prefabricated layer 114 on the two opposite surfaces of the carbon nanotube structure 112. The frame is a hollow structure with a through hole. The edge of the carbon nanotube structure 112 can be fixed in the frame, and the part located in the middle is exposed through the through hole and is suspended. Through the frame, the edge of the carbon nanotube structure 112 can be firmly fixed, and the carbon nanotube structure 112 located at the through hole position is kept fully exposed. In this embodiment, the frame is a "mouth"-shaped frame, and the edge of the carbon nanotube structure 112 is fixed by the frame. It can be understood that the carbon nanotube structure 112 can also be suspended by other means, such as a metal grid, a ring body with a hollow structure, etc., as long as the carbon nanotube structure 112 is suspended. The prefabricated layer 114 can be deposited on the surface of the carbon nanotube structure 112 by electron beam evaporation. It is understood that the deposition method is not limited to the above-mentioned methods, and can also be a vapor deposition method such as magnetron sputtering and atomic layer deposition, as long as the prefabricated layer 114 does not destroy the morphology and structure of the carbon nanotube structure 112 during the deposition process.

[0055] Since the carbon nanotube structure 112 is suspended, both surfaces of the carbon nanotube structure 112 are covered by the prefabricated layer 114. Specifically, the prefabricated layer 114 covers at least part of the surface of multiple carbon nanotubes in the carbon nanotube structure 112. The carbon nanotube structure 112 includes multiple microporous structures. It can be understood that the prefabricated layer 114 can also be distributed in the microporous structure. The carbon nanotubes in the carbon nanotube structure 112 are tightly combined with the prefabricated layer 114 to form an integral carbon nanotube composite structure 110. Among them, the carbon nanotube structure 112 plays a supporting role for the prefabricated layer 114. The carbon nanotube composite structure 110 includes multiple micropores 116. The micropores 116 are recessed spaces that run through the thickness direction of the carbon nanotube composite structure 110, and the recessed spaces can be gaps or micropores.

[0056] In this embodiment, the carbon nanotube composite structure 110 is obtained by arranging a prefabricated layer 114 on the surface of the carbon nanotube structure 112 by electron beam evaporation. The material of the prefabricated layer 114 is aluminum oxide, and the thickness of the prefabricated layer 114 is 5 nanometers. Each carbon nanotube in the carbon nanotube structure 112 is completely covered by the prefabricated layer 114. Figure 8 , is a scanning electron microscope photo of the carbon nanotube composite structure 110 used in this embodiment. Fig. 9, is a scanning electron microscope photograph of a single carbon nanotube coated with an aluminum oxide layer in the carbon nanotube composite structure 110 used in this embodiment.

[0057] In step S13, the carbon nanotube composite structure 110 can be directly disposed on the surface 123 of the intermediate layer 12. Specifically, the frame and the carbon nanotube composite structure 110 can be transferred to the surface 123 of the intermediate layer 12 together, and then the frame can be removed. Since the carbon nanotube composite structure 110 has a plurality of micropores 116, a portion of the surface 123 of the intermediate layer 12 is exposed through the plurality of micropores 116. The carbon nanotube composite structure 110 is not in complete close contact with the surface 123 of the intermediate layer 12, and air may exist between a portion of the carbon nanotube composite structure 110 and the surface 123 of the intermediate layer 12.

[0058] After the carbon nanotube composite structure 110 is disposed on the surface 123 of the intermediate layer 12, a step of treating the carbon nanotube composite structure 110 with a solvent so that the carbon nanotube composite structure 110 is attached to the surface 123 of the intermediate layer 12 may be further included. When a solvent is dripped onto the surface of the carbon nanotube composite structure 110, the solvent will infiltrate the carbon nanotube composite structure 110, soften the carbon nanotube composite structure 110, and discharge the air between the carbon nanotube composite structure 110 and the surface 123 of the intermediate layer 12. When the solvent is removed, the carbon nanotube composite structure 110 forms a close contact with the surface 123 of the intermediate layer 12. The solvent may be water, an organic solvent, etc. The organic solvent is a volatile organic solvent, such as ethanol, methanol, acetone, ethylene dichloride, and chloroform. In this embodiment, the solvent is ethanol. The ethanol is dripped onto the surface of the carbon nanotube composite structure 110 and then naturally dried, so that the carbon nanotube composite structure 110 is closely attached to the surface 123 of the intermediate layer 12 .

[0059] In step S14, the dry etching refers to introducing a gas to obtain a plasma under the action of an electric field, and the plasma can react with the etched material to obtain volatile substances, such as reactive ion etching (RIE) and inductively coupled plasma etching (ICPE). In this embodiment, the surface 123 of the exposed intermediate layer 12 is etched by reactive ion etching. Specifically, by introducing a gas into a plasma system, the gas can be oxygen, chlorine, hydrogen, chlorine, argon, carbon tetrafluoride, etc. The gas is not limited to the above-mentioned gases, as long as the gas can react with the intermediate layer 12. Preferably, the substrate 12 is etched by reactive ion etching of chlorine and argon, wherein the power of the plasma system is 20 watts to 70 watts, the introduction rate of chlorine plasma is 10 standard-state cubic centimeter per minute (sccm), the introduction rate of argon plasma is 40 sccm, the formed gas pressure is 2 Pa, and the etching time is 10 seconds to 400 seconds. The exposed surface of the intermediate layer 12 is partially etched by reactive ion etching. Since the plasma fully reacts with the intermediate layer 12, the reaction time of the process is short and the efficiency is high.

[0060] During the process of etching the intermediate layer 12, the etching gas chemically reacts with the exposed portion of the intermediate layer 12, but does not chemically react with the prefabricated layer 114 of the carbon nanotube composite structure 110, or the speed and degree of chemical reaction with the prefabricated layer 114 is much lower than the chemical reaction between the etching gas and the intermediate layer 12. That is, the carbon nanotube composite structure 110 acts as a mask. The materials of the etching gas and the intermediate layer 12 and the materials of the prefabricated layer 114 can be seen in Table 1 below.

[0061] Table 1 Correspondence between etching gas and the material of the intermediate layer and the material of the prefabricated layer

[0062] serial number Substrate material Materials for precast layers Etching gas 1 <![CDATA[SiO2]]> One of Al, Cr, Fe, Ti, Ni, or Au <![CDATA[CF4]]> 2 <![CDATA[SiN x ]]> One of Al, Cr, Fe, Ti, Ni, or Au <![CDATA[CF4]]> 3 GaN <![CDATA[Al2O3]]> <![CDATA[Cl2 and Ar2]]>

[0063] During the etching process, since the selected etching gas does not chemically react with the prefabricated layer 114 but chemically reacts with the intermediate layer 12, the surface of the exposed intermediate layer 12 will be gradually etched, while the surface of the intermediate layer 12 covered by the carbon nanotube composite structure 110 will not change. In addition, since the carbon nanotube composite structure 110 is tightly combined with the surface of the intermediate layer 12, the pattern formed by the surface of the intermediate layer 12 covered by the carbon nanotube composite structure 110 is consistent with the pattern formed by the forward projection of the carbon nanotube composite structure 110 onto the intermediate layer 12 when the carbon nanotube composite structure 110 is suspended in the air. That is, the overall pattern of the patterned protrusions 122 obtained in the end is basically consistent with the overall pattern of the carbon nanotube composite structure 110.

[0064] In this embodiment, when the carbon nanotube structure 112 uses a multi-layer cross carbon nanotube film, the patterned protrusions 122 with different patterns can be obtained by changing the cross angle of adjacent carbon nanotube films. When a forward cross carbon nanotube film is used as the carbon nanotube structure, the obtained patterned protrusions 122 include a plurality of convex strips arranged crosswise along two perpendicular directions.

[0065] The convex strips of the patterned protrusions 122 are strip-like or strip-like structures. The width of the convex strips is 20 nanometers to 150 nanometers. The spacing between two adjacent widths in the extension direction perpendicular to the carbon nanotubes is 10 nanometers to 300 nanometers. The size of the convex strips of the patterned protrusions 122 in the direction perpendicular to the surface of the intermediate layer 12 is defined as the height of the convex strips. The height of the convex strips is not limited and can be determined according to the specific etching time, and can be 50 nanometers to 1000 nanometers. The multiple convex strips are perpendicular to each other and cross-distributed to form a mesh structure. In this embodiment, the width of the convex strips is 50 nanometers to 100 nanometers, the spacing is 10 nanometers to 50 nanometers, and the height is 100 nanometers to 500 nanometers.

[0066] It can be understood that since the diameter and spacing of the composite structure after the carbon nanotubes in the carbon nanotube composite structure 110 are coated with the prefabricated layer 114 are both in the nanometer range, the width and spacing of the convex strips of the prepared patterned protrusions 122 are also in the nanometer range. Therefore, the patterned protrusions 122 and the plurality of holes 124 on the surface of the intermediate layer 12 are all nanostructures. The spacing between adjacent convex strips and the spacing between adjacent holes 124 on the surface of the intermediate layer 12 are both tens of nanometers, thus greatly improving the density of the nanostructure on the surface of the intermediate layer 12, thereby improving the SERS enhancement factor and enhancing Raman scattering. For example, when the spacing between adjacent convex strips and the spacing between adjacent holes 124 are both 20 nanometers, within the width range of 1 micron, the number of the convex strips and the number of holes 124 are both 50. In the prior art, the preparation of microstructures usually adopts photolithography technology. Due to the resolution limitation, it is difficult to control the nanostructure scale of the protrusions and depressions within the range of tens of nanometers.

[0067] In step S15, the method for removing the carbon nanotube composite structure 110 is not limited, and may be an ultrasonic method, a tearing method, an oxidation method, etc. In this embodiment, an ultrasonic method is used to remove the carbon nanotube composite structure 110. Specifically, the middle layer with the carbon nanotube composite structure 110 is placed in an N-methylpyrrolidone solution and ultrasonicated for several minutes. Since the polarity of N-methylpyrrolidone is relatively large, the carbon nanotube composite structure 110 can be easily separated from the middle layer.

[0068] In step S16, the method of depositing the metal layer 13 on the surface of the patterned protrusion 122 is not limited, and electron beam evaporation, ion beam sputtering, atomic layer deposition, magnetron sputtering, evaporation, chemical vapor deposition, etc. can be used. The metal layer 13 is deposited on the surface of each convex strip and the surface of the intermediate layer 12 between adjacent convex strips. The thickness of the metal layer 13 is 2 nanometers to 200 nanometers, and the material of the metal layer 13 is not limited, and can be a metal such as gold, silver, copper, iron or aluminum. In this embodiment, a 10-nanometer thick gold metal film is vertically evaporated on the surface of the intermediate layer 12, so that the patterned protrusion 122 is completely covered.

[0069] The preparation method of the molecular carrier provided by the present invention has the following advantages: the molecular carrier 10 prepared by using a flexible substrate can perform molecular detection on an irregular surface, and can realize in-situ detection on the surface of the object to be detected; the metal layer 13 is deposited on a mesh structure formed by multiple convex strips, so that under the excitation of the incident light, the metal surface plasma can undergo resonance absorption, and the convex strips of the network structure can play a role in surface enhanced Raman scattering, which can improve the SERS (Surface enhanced Raman scattering) enhancement factor and enhance Raman scattering. Moreover, a carbon nanotube structure is used as a skeleton, and the carbon nanotube structure has multiple micropores, so the obtained mask layer also has multiple micropores accordingly, and this method can easily realize a patterned mask layer. The preparation method is simple, efficient, and easy to industrialize.

[0070] See also Fig.10 The first embodiment of the present invention further provides a molecular detection method using the molecular carrier 10, and the detection method mainly includes the following steps:

[0071] Step S21, providing a sample 14 to be tested, wherein the surface of the sample 14 has molecules 15 to be tested distributed thereon;

[0072] Step S22, providing a molecular carrier 10, the molecular carrier 10 comprising a substrate 11, an intermediate layer 12 and a metal layer 13, the intermediate layer 12 being sandwiched between the substrate 11 and the metal layer 13; the intermediate layer 12 comprising a substrate 121 and a plurality of patterned protrusions 122 disposed on the substrate 121;

[0073] Step S23, attaching the surface of the metal layer 13 away from the substrate 11 to the surface of the sample 14 to form the molecules 15 of the sample on the surface of the metal layer 13;

[0074] Step S24 , using a detector to detect the molecules 15 of the object to be detected on the surface of the metal layer 13 .

[0075] In step S21, the surface of the sample 14 to be tested can be any surface, specifically, the surface of the sample 14 to be tested can be a plane, a curved surface or other irregular surface, such as the surface of an apple or a tomato. The type of the analyte molecule 15 is not limited, and can be arbitrarily distributed on the surface of the sample 14 to be tested, such as pesticides remaining on the surface of a tomato. In this embodiment, the analyte molecule is crystal violet (CV).

[0076] In step S23, since the substrate 11 is a flexible substrate, the molecular carrier 10 can be directly attached to the surface of the sample to be tested 14, and can be consistent with the curvature of the surface of the sample to be tested 14. Specifically, the metal layer 13 is directly in contact with the surface of the sample to be tested 14, and then, the molecules of the object to be tested 15 located on the surface of the sample to be tested 14 can be adhered to the metal layer 13 accordingly. Further, before the metal layer 13 is attached to the surface of the sample to be tested 14, an appropriate amount of solvent can be dripped on the surface of the sample to be tested 14, so that the molecules of the object to be tested 15 are dissolved in the solvent, and then the metal layer 13 is attached to the surface of the sample to be tested 14 dripped with the solvent. Since the molecules of the object to be tested 15 are dissolved in the solvent, the fluidity is improved, and it can be more easily attached to the surface of the metal layer 13. At the same time, the solvent dripped on the surface of the sample to be tested 14 can also expel the air between the sample to be tested 14 and the metal layer 13, so that the molecular carrier 10 is tightly adsorbed on the surface of the sample to be tested 14 without applying external force to fix it. The solvent may be water, ethanol, propanol, etc. The solvent may be dropped onto the surface of the sample 14 using a syringe. Specifically, the area of ​​the solvent spread on the surface of the sample 14 is equal to or slightly larger than the area of ​​the metal layer 13 .

[0077] In step S24, a detector such as a Raman spectrometer can be used to directly detect the analyte molecules 15 on the surface of the metal layer 13 in situ, without removing the molecular carrier 10 from the surface of the sample 14. The surface of the metal layer 13 away from the substrate 11 is set as the front side of the molecular carrier 10, and the surface of the substrate 11 away from the metal layer 13 is set as the back side of the molecular carrier 10. The detector can detect from the front side of the molecular carrier 10, and can also detect from the back side of the molecular carrier 10, and both can be used to detect the analyte molecules 15. Please refer to Fig.11 , the detector measures the spectra of different analyte concentrations from the front and back sides of the molecular carrier respectively. It can be seen from the figure that the spectra measured by the detector from the front and back sides are basically the same.

[0078] During the detection process, since the metal layer 13 is directly attached to the surface of the sample 14 to be detected, the laser emitted by the detector can be directly incident on the surface of the substrate 11 away from the metal layer 13 for detection, that is, the detector can be incident from the reverse side of the molecular carrier 10 for detection. Figure 12-13 , Figure 12-13 The following are the detection photos of crystal violet (CV) molecules on the surface of tomatoes detected by Raman spectrometer in situ and the results of the detection of different CV molecule concentrations. The laser wavelength is 633nm, the laser power is 0.1mW, and the exposure time is 5s.

[0079] When the detector directly incidents on the front of the molecular carrier 10 for detection, the metal layer 13 is first attached to the surface of the sample 14 to be tested, and the molecular carrier 10 is used to wipe the surface of the sample 14 to transfer part of the molecules 15 of the sample 14 to the surface of the metal layer 13, and then the molecular carrier 10 is removed. At this time, the detector can directly incident on the surface of the metal layer 13 for detection. Fig.14 , Fig.14 The figure below is a comparison of the detection spectrum (III) of p-aminothiophenol (4-ATP) molecules on the molecular carrier after wiping the apple surface with the molecular carrier and the detection spectrum (I, II) of the in-situ detection. The laser wavelength is 633nm, the laser power is 0.1mW, and the exposure time is 5s. It can be seen from the figure that the spectrum detected after wiping is basically consistent with the spectrum detected in-situ.

[0080] The single molecule detection method provided by the present invention has the following advantages: since the metal layer 13 is arranged on the surface of the patterned protrusion 122, and the patterned protrusion 122 includes a plurality of cross-arranged convex strips or a plurality of array-type convex block structures, under the excitation of external incident light, the metal surface plasma undergoes resonance absorption, and the cross-arranged convex strips or array-type convex blocks play a role in surface enhanced Raman scattering, which can improve the SERS enhancement factor and enhance Raman scattering. Since the molecular carrier 10 adopts a flexible substrate, the overall structure of the molecular carrier 10 can be bent at will with the flexible substrate, so that the molecular carrier 10 as a whole exhibits a flexible structure. Therefore, the molecular carrier 10 can perform molecular detection on irregular surfaces and can realize in-situ detection on the surface of the object to be detected, and the method is simple and fast.

[0081] See also Fig.15The second embodiment of the present invention provides a molecular carrier 20 for molecular detection, and the molecular carrier 20 includes a substrate 11, an intermediate layer 12, a carbon nanotube composite structure 110 and a metal layer 13. Specifically, the intermediate layer 12 is arranged on the surface of the substrate 11, the carbon nanotube composite structure 110 is arranged on the surface of the intermediate layer 12 away from the substrate, and the metal layer 13 is arranged on the surface of the carbon nanotube composite structure 110. The intermediate layer 12 includes a substrate 121 and a plurality of patterned protrusions 122 arranged on the substrate 121, and the patterned protrusions 122 are arranged on the surface of the substrate 121 away from the substrate 11. The patterned protrusions 122 include a plurality of convex strips arranged crosswise to form a mesh structure, thereby defining a plurality of holes 124. The intersection of the plurality of convex strips is an integrated structure.

[0082] The molecular carrier 20 provided in the second embodiment of the present invention has a substantially similar structure to the molecular carrier 10 provided in the first embodiment, except that it further comprises a carbon nanotube composite structure 110 disposed between the top surface of the patterned protrusion 122 and the metal layer 13. The metal layer 13 completely covers the patterned protrusion 122 and the carbon nanotube composite structure 110.

[0083] See also Fig.16 The second embodiment of the present invention provides a method for preparing the above-mentioned molecular carrier 20, which comprises the following steps:

[0084] Step S31, providing an intermediate layer 12 disposed on a substrate 11;

[0085] Step S32, disposing a carbon nanotube composite structure 110 on a surface 123 of the intermediate layer 12, so that the surface 123 of the intermediate layer 12 is partially exposed;

[0086] Step S33, using the carbon nanotube composite structure 110 as a mask to dry-etch the intermediate layer 12, thereby obtaining an intermediate layer 12 having a patterned protrusion 122, wherein the patterned protrusion 122 includes a plurality of cross-arranged protrusions;

[0087] Step S34 , depositing a metal layer 13 on the surface of the carbon nanotube composite structure 110 , and the metal layer 13 completely covers the carbon nanotube composite structure 110 and the intermediate layer 12 .

[0088] The preparation method of the molecular carrier 20 provided in the second embodiment of the present invention is basically the same as the preparation method of the molecular carrier 10 provided in the first embodiment, except that in this embodiment, the carbon nanotube composite structure 110 does not need to be removed, but a metal layer 13 is directly deposited on the carbon nanotube composite structure 110, and the metal layer 13 completely covers the carbon nanotube composite structure 110 and the intermediate layer 12. In this preparation method, the carbon nanotube composite structure 110 is used as a mask for etching the intermediate layer 12 and as a mask for depositing the metal layer 13, which not only saves preparation cost but also improves preparation efficiency.

[0089] The second embodiment of the present invention further provides a molecular detection method using the molecular carrier 20. This method is basically the same as the molecular detection method using the molecular carrier 10 provided in the first embodiment of the present invention, except that different molecular carriers are used.

[0090] See also Fig.17 The third embodiment of the present invention provides a molecular carrier 30 for molecular detection, which includes a substrate 11, an intermediate layer 12 and a metal layer 13. Specifically, the intermediate layer 12 is arranged on the surface of the substrate 11, and the metal layer 13 is arranged on the surface of the intermediate layer 12. The intermediate layer 12 includes a substrate 121 and a plurality of patterned protrusions 122 arranged on the substrate 121, and the patterned protrusions 122 are arranged on the surface of the substrate 121 away from the substrate 11. The patterned protrusions 122 include a plurality of convex strips arranged crosswise to form a mesh structure, thereby defining a plurality of holes 124. The intersection of the plurality of convex strips is an integrated structure.

[0091] The molecular carrier 30 provided in the third embodiment of the present invention has a substantially similar structure to the molecular carrier 10 provided in the first embodiment, except that the metal layer 13 is a discontinuous structure. Specifically, the metal layer 13 is only provided on the side walls of the convex strips and the surface of the substrate 121 between adjacent convex strips. That is, the metal layer 13 is only provided on the side walls and bottom surface of the hole 124.

[0092] See also Fig.18 The third embodiment of the present invention provides a method for preparing the above-mentioned molecular carrier 30, which comprises the following steps:

[0093] Step S41, providing an intermediate layer 12 disposed on a substrate 11;

[0094] Step S42, disposing a carbon nanotube composite structure 110 on a surface 123 of the intermediate layer 12, so that the surface 123 of the intermediate layer 12 is partially exposed;

[0095] Step S43, using the carbon nanotube composite structure 110 as a mask to dry-etch the intermediate layer 12, thereby obtaining an intermediate layer 12 having a patterned protrusion 122, wherein the patterned protrusion 122 includes a plurality of cross-arranged protrusions;

[0096] In step S44 , a metal layer 13 is deposited on the surface of the carbon nanotube composite structure 110 , and the metal layer 13 completely covers the carbon nanotube composite structure 110 and the intermediate layer 12 .

[0097] Step S45 , removing the carbon nanotube composite structure 110 .

[0098] The preparation method of the molecular carrier 30 provided in the third embodiment of the present invention is basically the same as the preparation method of the molecular carrier 20 provided in the second embodiment, the difference being that after a metal layer 13 is deposited on the surface of the patterned protrusion 122, the carbon nanotube composite structure 110 is removed. In step S44, part of the metal layer 13 is deposited on the surface of the carbon nanotube composite structure 110, and the other part is deposited on the side of the convex strip and between adjacent convex strips. In step S45, part of the metal layer 13 deposited on the surface of the carbon nanotube composite structure 110 is removed together with the carbon nanotube composite structure 110, forming a discontinuous metal layer 13 on the surface of the intermediate layer 12. At the same time, in the actual preparation process, after the carbon nanotube composite structure is removed, some metal layer corners will remain at the junction of the top surface and the side surface of the convex strip, and these metal corner particles or small gaps will enhance the SERS enhancement effect. In the method of the third embodiment of the present invention, the carbon nanotube composite structure 110 is used as both a mask for etching the intermediate layer 12 and a mask for depositing the metal layer 13, which not only saves the preparation cost but also improves the preparation efficiency.

[0099] The third embodiment of the present invention further provides a single molecule detection method using the molecular carrier 30. This method is basically the same as the molecular detection method using the molecular carrier 20 provided in the second embodiment of the present invention, except that different molecular carriers are used.

[0100] See also Fig.19 The fourth embodiment of the present invention provides a molecular detection device 1 of the above-mentioned molecular carriers 10, 20, 30. This embodiment only takes the molecular carrier 10 as an example. The molecular detection device 1 includes a molecular carrier 10, a fixing element 16 for fixing the molecular carrier 10 on the surface of a sample to be tested, a detector 17 for detecting the molecules of the sample to be tested on the surface of the molecular carrier 10, and a control computer 18 connected to the detector 17.

[0101] The fixing element 16 is any fixing device that can fix the molecular carrier 10 to the surface of the sample to be detected. Specifically, the fixing element 16 can be a fixing belt, which is used to tie the molecular carrier 10 to the surface of the sample to be detected, and the fixing belt does not cover all the patterned protrusions 122 of the molecular carrier 10. Fig. 20 The fixing element 16 can also be a bendable metal frame, and the edge of the substrate 11 is fixed on the metal frame. The metal frame can be bent at the same time as the molecular carrier, so that the metal frame can fix the molecular carrier on the surface of the sample to be tested 14. It can be understood that when the molecular carrier 10 can be attached to the surface of the sample to be tested 14 alone, the fixing element 16 is an optional element. The detector 17 can be a Raman spectrometer or other detectors capable of realizing molecular detection.

[0102] For further information, see Fig.21 The molecular detection device 1 may include a plurality of molecular carriers 10, and the plurality of molecular carriers 10 are connected to each other to form a molecular carrier strip. Specifically, the plurality of molecular carriers 10 may share the same substrate, and the patterned protrusions of the plurality of molecular carriers are located on the same surface of the substrate. Since the molecular carrier is a flexible structure, the molecular carrier strip can be rolled into a cylindrical shape to save space, and can be cut as needed when in use, which is convenient to use.

[0103] When the molecular detection device 1 is used, the molecular carrier 10 is fixed to the surface of the sample to be detected by the fixing element 16, and then the detector 17 is used to detect the molecules of the object to be detected on the surface of the molecular carrier 10, and the detector 17 sends the detection result to the control computer 18. The control computer 18 analyzes the detection result, thereby realizing real-time dynamic monitoring of the molecules of the object to be detected.

[0104] In addition, those skilled in the art may also make other changes within the spirit of the present invention. Of course, these changes made according to the spirit of the present invention should be included in the scope of protection required by the present invention.

Claims

1. A molecular carrier for molecular detection, comprising: a base; an intermediate layer disposed on the surface of the substrate; a metal layer, disposed on a surface of the intermediate layer away from the substrate; It is characterized in that the base is a flexible base; the intermediate layer includes a substrate and a plurality of patterned protrusions arranged on the substrate, the patterned protrusions include a plurality of convex strips arranged crosswise to form a network structure, thereby defining a plurality of holes, and the metal layer is arranged on the side walls of the plurality of convex strips and in the holes between adjacent convex strips; the material of the substrate is one of silicon dioxide, silicon nitride, gallium nitride, and gallium arsenide, the thickness of the substrate is 100 nanometers to 200 nanometers, and the molecular carrier as a whole is a flexible structure.

2. The molecular carrier according to claim 1, characterized in that The material of the substrate is one of polyethylene terephthalate, polyimide, polymethyl methacrylate, polydimethylsiloxane, and polyethylene naphthalate.

3. The molecular carrier according to claim 1, characterized in that The multiple ridges include multiple first ridges extending along a first direction and multiple second ridges extending along a second direction. The angle between the first direction and the second direction is greater than or equal to 30 degrees and less than or equal to 90 degrees. The width of each ridge is 20 nanometers-150 nanometers, the height is 100 nanometers-500 nanometers, and the spacing between two adjacent parallel ridges is 10 nanometers-300 nanometers.

4. The molecular carrier according to claim 1, characterized in that The width of each convex strip is 50 nanometers to 100 nanometers, the height is 200 nanometers to 400 nanometers, and the spacing between two adjacent parallel convex strips is 10 nanometers to 50 nanometers.

5. The molecular carrier according to claim 1, characterized in that The metal layer is a continuous layered structure, and the metal layer is arranged on the surfaces of the plurality of convex strips and in the holes between the convex strips.

6. The molecular carrier according to claim 1, characterized in that The metal layer is a discontinuous layered structure, and the metal layer is only arranged on the side walls of a plurality of convex strips and in the holes between adjacent convex strips.

7. The molecular carrier according to claim 1, characterized in that The thickness of the metal layer ranges from 2 nanometers to 200 nanometers.

8. The molecular carrier according to claim 1, characterized in that It further comprises a fixing element, which is used to fix the metal layer to the surface of the object to be tested, and the fixing element is one of a fixing belt and a bendable metal frame.

Images