A chiral molecule detection substrate based on chiral carbon quantum dots

Abstract

The present invention relates to the field of chiral molecule detection, and specifically to a chiral molecule detection substrate based on chiral carbon quantum dots, comprising a substrate, a carrier layer, and chiral carbon quantum dots; the carrier layer is placed on the substrate, and periodically arranged holes are provided on the surface of the carrier layer, the holes do not penetrate the carrier layer, and the chiral carbon quantum dots are arranged on the side and bottom of the holes. When used, the chiral molecule is placed in the hole. Circularly polarized light is used to irradiate the carrier layer and the hole. The combination of the chiral molecule and the chiral carbon quantum dot has different chiral responses, resulting in the movement of the fluorescence emission peak, and the chiral molecule detection is achieved through the movement of the fluorescence emission peak. The present invention uses chiral carbon quantum dots instead of chiral noble metal structures, because the chiral carbon quantum dots can be prepared by traditional chemical methods, and the cost is low, which leads to low cost of the chiral molecule detection device of the present invention, and has good application prospects in the field of chiral molecule detection.

Description

Technical Field

[0001] The invention relates to the field of chiral molecule detection, and in particular to a chiral molecule detection substrate based on chiral carbon quantum dots. Background Art

[0002] Chiral molecule detection or identification has important applications in life sciences, drug research, food and other fields. The main current chiral detection or identification methods include liquid chromatography, nuclear magnetic resonance, etc. These methods rely on signal generators or signal detection devices, and the equipment is expensive. Exploring low-cost, high-sensitivity chiral molecule detection or identification technology is a hot topic and difficulty in current research. Because most chiral molecules have circular dichroism, circular dichroism spectroscopy is often used for chiral molecule detection. However, the circular dichroism of chiral molecules is weak and is in the ultraviolet region, which is not conducive to detection by conventional detectors. Exploring chiral molecule detection methods based on circular dichroism has important application value.

[0003] The paper Ultrasensitive detection and characterization of biomolecules using superchiral fields (Nature Nanotechnology, 5, 783, 2010) published in 2010 prepared a swastika-shaped noble metal chiral structure, set lactoglobulins of different chirality on the swastika-shaped noble metal chiral structure, and realized the detection of chiral lactoglobulins by detecting the movement of the resonance wavelength in the circular dichroism spectrum. In this technology, the preparation of chiral noble metal micro-nanostructures is difficult and costly, and the interaction between chiral noble metal micro-nanostructures and chiral molecules is weak, resulting in weak response and increasing the difficulty of detection. In short, it is of great significance to explore new chiral molecule detection methods and corresponding devices. Summary of the invention

[0004] To solve the above problems, the present invention provides a chiral molecule detection substrate based on chiral carbon quantum dots, including a substrate, a supporting layer, and chiral carbon quantum dots; the supporting layer is placed on the substrate, and the surface of the supporting layer is provided with periodically arranged holes, the holes do not penetrate the supporting layer, and the chiral carbon quantum dots are arranged on the side and bottom of the holes.

[0005] Furthermore, the material of the substrate is glass or silicon.

[0006] Furthermore, the material of the bearing layer is quartz glass.

[0007] Furthermore, the period of hole arrangement is a square period.

[0008] Furthermore, the hole is circular.

[0009] Furthermore, the diameter of the pores is less than 200 nanometers.

[0010] Furthermore, the chiral carbon quantum dots are larger than 1 nanometer and smaller than 10 nanometers.

[0011] Furthermore, the material of the bearing layer is a precious metal.

[0012] Furthermore, the material of the noble metal is gold.

[0013] Furthermore, at the bottom of the hole, the thickness of the support layer is greater than 100 nanometers.

[0014] Beneficial effects of the present invention: The present invention provides a chiral molecule detection substrate based on chiral carbon quantum dots, including a substrate, a supporting layer, and chiral carbon quantum dots; the supporting layer is placed on the substrate, and the surface of the supporting layer is provided with periodically arranged holes, the holes do not penetrate the supporting layer, and the chiral carbon quantum dots are arranged on the side and bottom of the holes. When used, the chiral molecules are placed in the holes. Circularly polarized light is used to irradiate the supporting layer and the holes. Because chiral molecules and chiral carbon quantum dots have specific chirality, the combination of chiral molecules with different chirality and chiral carbon quantum dots has different chiral responses, resulting in the movement of the fluorescence emission peak, and chiral molecule detection is achieved through the movement of the fluorescence emission peak. The present invention uses chiral carbon quantum dots instead of chiral precious metal structures, because chiral carbon quantum dots can be prepared by traditional chemical methods, and the cost is low, which leads to low cost of the chiral molecule detection device of the present invention, and has good application prospects in the field of chiral molecule detection.

[0015] The present invention will be further described in detail below with reference to the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 A schematic diagram of a chiral molecule detection substrate based on chiral carbon quantum dots.

[0017] Figure 2 This is a schematic diagram of another chiral molecule detection substrate based on chiral carbon quantum dots.

[0018] In the figure: 1. substrate; 2. supporting layer; 3. chiral carbon quantum dots. DETAILED DESCRIPTION

[0019] In order to make the objectives, technical solutions and advantages of the present application more clearly understood, the present application is further described in detail below with reference to the accompanying drawings and examples.

[0020] Example 1

[0021] The present invention provides a chiral molecule detection substrate based on chiral carbon quantum dots, such as Figure 1As shown, it includes a substrate 1, a carrier layer 2, and chiral carbon quantum dots 3. The material of the substrate 1 is glass or silicon, and the substrate 1 is used to support the carrier layer. In the present invention, the excitation light and the detector are both arranged on the upper side of the carrier layer 2, so the material of the substrate 1 has little effect on the present invention. The carrier layer 2 is placed on the substrate 1. The material of the carrier layer 2 is quartz glass to reduce the absorption of ultraviolet light or near-ultraviolet light by the carrier layer 2. The surface of the carrier layer 2 is provided with periodically arranged holes, and the holes do not penetrate the carrier layer. The holes can be prepared by ion beam etching. The period of the hole arrangement is a square period. The holes are circular to facilitate the formation of a stronger chiral electromagnetic field in the hole, and the chiral electromagnetic field excites the chiral carbon quantum dots 3 to produce fluorescence. The diameter of the hole is less than 200 nanometers, so as to facilitate the collection of ultraviolet light or near-ultraviolet light used for excitation. The chiral carbon quantum dots 3 are arranged on the side and bottom of the hole. The chiral carbon quantum dots 3 are greater than 1 nanometer and less than 10 nanometers. In the present invention, the holes not only have the function of gathering the chiral electromagnetic field, but also have the function of gathering the chiral molecules. In addition, the holes in the carrier layer 2 are equivalent to increasing the surface area of ​​the carrier layer 2, so that more chiral carbon quantum dots 3 can be arranged, the interaction between the incident light and the chiral carbon quantum dots 3 is improved, and the intensity of the fluorescence generated by the chiral carbon quantum dots 3 is enhanced, which is more conducive to detection.

[0022] When used, the chiral molecule is set in the hole. Circularly polarized light is used to irradiate the carrier layer 2 and the hole. Because the axis of the hole is along the normal direction of the carrier layer 2, the circularly polarized light vertically irradiates the carrier layer 2 and the hole, so as to form a strong chiral electromagnetic field in the hole. The wavelength of the incident light is ultraviolet light or near-ultraviolet light. Because the chiral molecules and the chiral carbon quantum dots 3 have specific chirality, the combination of chiral molecules with different chirality and chiral carbon quantum dots 3 has different chiral responses, resulting in the movement of the fluorescence emission peak, and the detection of chiral molecules is achieved through the movement of the fluorescence emission peak.

[0023] Invention patent CN114045171A discloses a method for preparing chiral carbon quantum dots 3, wherein chirality is introduced by L-cysteine, and chiral carbon quantum dots 3 can be obtained by conventional sugarcane molasses, ultrapure water, and conventional reactors, and operations such as filtration and centrifugation. The preparation method has low cost, simple preparation process, and easy control of process conditions, resulting in low cost of chiral carbon quantum dots 3.

[0024] Therefore, the present invention uses chiral carbon quantum dots 3 instead of chiral noble metal micro-nano structures, which is low in cost, resulting in low cost of the chiral molecule detection device of the present invention, and has good application prospects in the field of chiral molecule detection.

[0025] In addition, in the present invention, the chiral carbon quantum dots 3 are distributed on the side and bottom of the hole, and have a longer distribution distance along the light incident direction. Compared with the single-layer chiral metal nanostructure, the incident light can have a stronger effect on the chiral carbon quantum dots 3. The size of the traditional chiral noble metal micro-nanostructure is large, and the coupling between the different parts of the chiral noble metal micro-nanostructure leads to chirality. The effect of the incident circularly polarized light on the chiral noble metal micro-nanostructure is weak. In the present invention, the size of the chiral carbon quantum dots 3 is small, and it can generate chiral signals by itself. A large number of chiral carbon quantum dots 3 can be set in the hole, which enhances the effect of the incident circularly polarized light on the chiral carbon quantum dots 3, making the chiral response easier to detect.

[0026] Example 2

[0027] On the basis of Example 1, the material of the carrier layer 2 is a noble metal. The material of the noble metal is gold. The noble metal has surface plasmon characteristics, which can gather a stronger light field in the hole and confine the strong light field in the hole, thereby stimulating the chiral carbon quantum dots 3 in the hole to produce stronger fluorescence, and also enhancing the interaction between the chiral molecules and the chiral carbon quantum dots 3, so that the chiral carbon quantum dots The luminescent wavelength moves more, thereby improving the sensitivity of chiral molecule detection.

[0028] Furthermore, at the bottom of the hole, the thickness of the supporting layer 2 is greater than 100 nanometers, and the bottom of the supporting layer 2 will not transmit the incident light into the substrate 1, thereby playing the role of collecting the incident light, thereby forming a strong chiral electromagnetic field in the hole. In addition, this also makes it easier for the precious metal material at the bottom of the hole to reflect the fluorescence, thereby detecting stronger fluorescence on the upper side of the supporting layer 2.

[0029] Example 3

[0030] On the basis of Example 2, Figure 2 As shown, the top of the hole is thick and the bottom of the hole is thin. In this way, the hole has more side surface area, and more chiral carbon quantum dots 3 can be set; in addition, it is also conducive to gathering incident light to form a strong electromagnetic field in the hole, especially forming a strong chiral field at the bottom of the hole. When setting chiral carbon quantum dots 3, it is also easy to set more chiral carbon quantum dots 3 there. The strong chiral electromagnetic field at the bottom of the hole enhances the interaction between the chiral molecules and the chiral carbon quantum dots 3, resulting in more movement of the fluorescence emission peak, thereby improving the sensitivity of the detection of the concentration of chiral molecules.

[0031] Example 4

[0032] On the basis of Example 3, the top of the carrier layer 2 is made of quartz glass, and the bottom of the carrier layer 2 is made of precious metal material. For example, half the thickness of the carrier layer 2 is made of quartz glass, and half the thickness of the carrier layer 2 close to the substrate is made of precious metal material. In this way, the carrier layer 2 absorbs less fluorescence, which is conducive to improving the fluorescence intensity detected at the top of the carrier layer 2 and reducing the difficulty of detection.

[0033] The above description is only a preferred embodiment of the present application and is not intended to limit the present application. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present application shall be included in the scope of protection of the present application.

Claims

1. A chiral molecule detection substrate based on chiral carbon quantum dots, characterized in that: It includes a substrate, a supporting layer, and chiral carbon quantum dots; the supporting layer is placed on the substrate, the surface of the supporting layer is provided with periodically arranged holes, the holes do not penetrate the supporting layer, and the chiral carbon quantum dots are arranged on the side and bottom of the holes, wherein the holes are circular, the diameter of the holes is less than 200 nanometers, the top of the holes is coarse, and the bottom of the holes is thin, the top of the supporting layer is quartz glass, and the bottom of the supporting layer is precious metal.

2. The chiral molecular detection substrate based on chiral carbon quantum dots according to claim 1, characterized in that: The substrate is made of glass or silicon.

3. The chiral molecular detection substrate based on chiral carbon quantum dots according to claim 1, characterized in that: The period of the hole arrangement is a square period.

4. The chiral molecular detection substrate based on chiral carbon quantum dots according to claim 1, characterized in that: The chiral carbon quantum dots are larger than 1 nanometer and smaller than 10 nanometers.

5. The chiral molecular detection substrate based on chiral carbon quantum dots according to claim 1, characterized in that: The material of the noble metal is gold.

6. The chiral molecular detection substrate based on chiral carbon quantum dots according to claim 5, characterized in that: At the bottom of the hole, the thickness of the supporting layer is greater than 100 nanometers.

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