Electrochemiluminescence microfluidic chip for multiple tumor marker detection

Abstract

This invention discloses an electrochemiluminescence microfluidic chip for the detection of multiple tumor markers, relating to the field of biodetection technology. It includes a substrate and a microfluidic channel system, an electrochemiluminescence detection unit, and a signal acquisition interface integrated on the substrate. The microfluidic channel system includes a sample inlet, a shunt structure, multiple parallel and equally spaced detection channels, and a waste liquid pool connected in sequence. The shunt structure includes a main channel and multiple branch channels integrally formed with the main channel. In this invention, the microfluidic channel system, the electrochemiluminescence detection unit, and the signal acquisition interface are integrated on the same substrate, achieving an integrated design for sample transmission, reaction, detection, and signal export. Compared to traditional distributed detection technologies, this significantly simplifies the detection operation steps, reduces the professional skills required of operators, and shortens the detection cycle, meeting the needs of rapid clinical diagnosis.

Description

Technical Field

[0001] This invention belongs to the field of biodetection technology, specifically, it relates to an electrochemiluminescence microfluidic chip for the detection of multiple tumor markers. Background Technology

[0002] Cancer, as a major disease that seriously threatens human life and health, relies heavily on early screening and accurate diagnosis to improve patient survival rates and treatment outcomes. Tumor markers are specific substances produced by tumor cells during their occurrence and development. Changes in their levels in biological samples are closely related to the occurrence, progression, and metastasis of tumors. Therefore, detecting the types and levels of tumor markers can provide important reference data for early screening, diagnosis, efficacy evaluation, and prognostic monitoring of cancer. With the continuous development of medical diagnostic technologies, combined detection of multiple tumor markers has become an important trend in the field of cancer diagnosis because it effectively improves the accuracy and comprehensiveness of detection and reduces the risk of missed diagnoses and misdiagnoses associated with single-marker detection.

[0003] Microfluidic chip technology has gained widespread attention in the field of biological detection due to its advantages such as miniaturization, integration, small sample volume, and high detection speed. Combining microfluidic technology with electrochemiluminescence detection technology holds promise for achieving efficient and accurate detection of tumor markers. However, existing tumor marker detection technologies based on microfluidic chips still have some shortcomings: on the one hand, the integration level of the chips is insufficient, and the synergistic effect between the microfluidic channel system and the detection unit is poor, making it difficult to achieve simultaneous and stable detection of multiple markers; on the other hand, unreasonable shunt structure design leads to uneven sample distribution, affecting the consistency of multi-channel detection results; in addition, the performance of the detection electrodes and the stability of signal transmission need to be improved, and the detection sensitivity and reliability of some chips cannot meet the stringent requirements of clinical testing. No effective solutions have yet been proposed to address the problems in the relevant technologies.

[0004] Therefore, in order to solve the above problems, the present invention provides an electrochemiluminescence microfluidic chip for the detection of multiple tumor markers. Summary of the Invention

[0005] In order to overcome the above-mentioned technical problems, the purpose of this invention is to provide an electrochemiluminescence microfluidic chip for the detection of multiple tumor markers.

[0006] The objective of this invention can be achieved through the following technical solutions: An electrochemiluminescence microfluidic chip for the detection of multiple tumor markers includes a substrate and a microfluidic channel system, an electrochemiluminescence detection unit, and a signal acquisition interface integrated on the substrate; The microfluidic channel system includes a sample inlet, a diversion structure, multiple parallel and equally spaced detection channels, and a waste liquid pool connected in sequence. The diversion structure includes a main channel and multiple branch channels integrally formed with the main channel. Each branch channel has the same length and inner diameter and is connected to each detection channel in a one-to-one correspondence, used to divert the sample equally to each detection channel. The inner wall of each detection channel is chemically coupled with specific capture probes for different tumor markers. The electrochemiluminescence detection unit includes a detection electrode group independently set for each detection channel. The detection electrode group is embedded in the substrate and located below the detection channel, and consists of a working electrode, a reference electrode, and a counter electrode. The signal acquisition interface is electrically connected to each detection electrode group through conductive lines embedded in the substrate, and is used to stably export the electrochemiluminescence signal to the external detection device.

[0007] As a preferred embodiment of the present invention, the substrate is made of polydimethylsiloxane or glass, and the substrate has grooves that match the microfluidic channel system, the inner walls of the grooves being hydrophilically treated.

[0008] As a preferred embodiment of the present invention, the surface of the working electrode is covered with an electroluminescent material layer by sputtering, wherein the electroluminescent material layer is a ruthenium bipyridine derivative layer.

[0009] As a preferred embodiment of the present invention, the diversion structure is a symmetrical tree-shaped diversion channel, with the inner diameter of the main channel being 200-500 μm and the inner diameter of the branch channels being 50-200 μm.

[0010] As a preferred embodiment of the present invention, the inner diameter of the plurality of detection channels is consistent, all being 50-500μm, and the length difference between each detection channel does not exceed 5%.

[0011] In a preferred embodiment of the present invention, the reference electrode is a silver or silver chloride electrode, the counter electrode is a platinum electrode, and the working electrode is a gold electrode or a carbon electrode.

[0012] Compared with the prior art, the present invention has the following beneficial effects: 1. In this invention, the microfluidic channel system, electrochemiluminescence detection unit and signal acquisition interface are integrated on the same substrate, realizing an integrated design of sample transmission, reaction, detection and signal export. Compared with traditional distributed detection technology, it greatly simplifies the detection operation steps, reduces the professional skills required of operators, and shortens the detection cycle, thus meeting the needs of rapid clinical diagnosis.

[0013] 2. Based on the miniaturization advantages of microfluidic technology, the microfluidic channel system of this invention is small in size and can complete the detection of multiple tumor markers with only a small amount of sample, effectively solving the problem of large sample volume in traditional detection technologies, and has good applicability to the detection of scarce biological samples in clinical practice.

[0014] 3. In this invention, by setting up multiple parallel and equally spaced detection channels and fixing specific capture probes for different tumor markers on the inner wall of each channel, combined with the equal-volume diversion effect of the symmetrical tree-like diversion structure, the simultaneous detection of multiple tumor markers can be completed with a single sample import. Compared with the traditional method of multiple independent detections, the detection efficiency is greatly improved, while avoiding the systematic errors caused by multiple detections and improving the comparability of detection results.

[0015] 4. In this invention, the diversion structure adopts a symmetrical tree-like design, and the length and inner diameter of each branch channel are the same. Simultaneously, the inner diameter of the detection channels is consistent, and the length difference does not exceed 5%. This ensures uniform sample distribution within each detection channel and that the flow state is consistent with the reaction environment, effectively improving the consistency and accuracy of multi-channel detection results. 5. In this invention, the chip adopts an integrated micro-design, which is small in size and light in weight. It does not require a large number of supporting equipment, is easy to carry and transport, and can realize rapid on-site and bedside testing. It breaks the dependence of traditional testing technology on professional laboratory environment and expands the applicability of testing scenarios. Attached Figure Description

[0016] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0017] Figure 1 This is a schematic diagram of the structure of the present invention.

[0018] Figure label: 1. Substrate; 2. Sample inlet; 3. Flow shunt structure; 4. Detection channel; 5. Waste liquid tank; 6. Specific capture probe; 7. Detection electrode assembly; 8. Signal acquisition interface. Detailed Implementation

[0019] The preferred embodiments of the present invention will now be described in detail with reference to the accompanying drawings, so that the advantages and features of the present invention can be more easily understood by those skilled in the art, thereby providing a clearer and more explicit definition of the scope of protection of the present invention: Example: Please refer to Figure 1According to an embodiment of the present invention, an electrochemiluminescence microfluidic chip for the detection of multiple tumor markers includes a substrate 1 and a microfluidic channel system, an electrochemiluminescence detection unit, and a signal acquisition interface 8 integrated on the substrate 1. The substrate 1 is made of polydimethylsiloxane or glass. The substrate 1 has grooves that match the microfluidic channel system. The inner wall of the grooves is hydrophilically treated. The substrate 1 serves as the basic support structure of the chip, providing a carrier for the integrated installation of the microfluidic channel system, the electrochemiluminescence detection unit, and the signal acquisition interface 8, ensuring the stable assembly and collaborative operation of each component. The selected polydimethylsiloxane or glass material has good biocompatibility, chemical stability, and processing adaptability, and the hydrophilically treated grooves can ensure smooth fluid flow, providing basic support for the overall performance of the chip.

[0020] Please see Figure 1 The microfluidic channel system includes a sample inlet 2, a flow branching structure 3, multiple parallel and equally spaced detection channels 4, and a waste liquid tank 5, all connected in sequence. The sample inlet 2 facilitates the introduction of the detection sample, providing a convenient and precise entry point for the sample into the microfluidic channel system. The waste liquid tank 5 collects waste liquid after detection, preventing waste liquid from lingering in the channel and contaminating the chip or affecting the detection process. This ensures smooth fluid circulation within the microfluidic channel system, improving the chip's safety and cleanliness. The flow branching structure 3 includes a main channel and multiple branch channels integrally formed with the main channel. Each branch channel has the same length and inner diameter and is connected one-to-one to each detection channel. Channel 4 is used to distribute samples equally to each detection channel 4. The diversion structure 3 distributes the samples introduced from the sample inlet 2 equally to ensure that each sample enters each parallel detection channel 4 in a consistent amount. The inner wall of each detection channel 4 is fixed with specific capture probes 6 for different tumor markers through chemical coupling. The specific capture probes 6 specifically identify and bind to the target tumor markers to achieve targeted capture and enrichment of different tumor markers. They are fixed to the inner wall of the detection channel 4 through chemical coupling, which is firm and not easy to fall off. They are highly specific and can effectively improve the specificity and sensitivity of the detection, providing core support for multi-target detection.

[0021] Please see Figure 1 The electrochemiluminescence detection unit includes a detection electrode group 7 independently set for each detection channel 4. The detection electrode group 7 is embedded in the substrate 1 and located below the detection channel 4. It consists of a working electrode, a reference electrode, and a counter electrode. The detection electrode group 7 generates an electrochemiluminescence signal and completes signal conversion, converting the biological signal after the tumor marker is bound into a detectable electrical signal and optical signal. Its design of being independently set below each detection channel 4 enables independent detection of signals from each channel. The combination of the working electrode, reference electrode, and counter electrode has stable electrochemical performance, high signal conversion efficiency, and good stability.

[0022] Please see Figure 1 The signal acquisition interface 8 is electrically connected to each detection electrode group 7 through conductive lines embedded in the substrate 1. The signal acquisition interface 8 outputs the electrochemiluminescence signal generated by the detection electrode group 7, realizing stable signal transmission between the chip and external detection equipment. The one-to-one electrical connection is achieved through conductive lines embedded in the substrate 1, resulting in low signal transmission loss and high stability, which can ensure accurate acquisition of detection signals by external equipment.

[0023] Please see Figure 1 The surface of the working electrode is coated with an electroluminescent material layer by sputtering. The electroluminescent material layer is a ruthenium bipyridine derivative layer. The electroluminescent material layer endows the working electrode with efficient electroluminescence performance and provides a stable signal source for electrochemiluminescence detection. The ruthenium bipyridine derivative layer prepared by sputtering has the characteristics of good uniformity and strong bonding. The material has high electroluminescence efficiency and stable signal, which can significantly improve the sensitivity and reliability of detection.

[0024] Please see Figure 1 The shunt structure 3 is a symmetrical tree-shaped shunt channel. The inner diameter of its main channel is 200-500μm, and the inner diameter of its branch channels is 50-200μm. The structural design of the symmetrical tree-shaped shunt channel conforms to the principles of fluid mechanics. With the limited inner diameter range, it can effectively avoid sample loss and uneven distribution during the shunt process, ensuring the accuracy of multi-channel parallel detection. At the same time, the specific size parameters are adapted to the miniaturization requirements of microfluidic chips.

[0025] Please see Figure 1 The inner diameter of multiple detection channels 4 is consistent, ranging from 50 to 500 μm, and the length difference of each detection channel 4 does not exceed 5%. The uniform inner diameter and strictly controlled length difference can ensure that the reaction conditions of tumor markers and capture probes 6 are uniform in different detection channels, thereby improving the comparability and accuracy of multi-index detection results and meeting the high-precision detection requirements of microfluidic chips.

[0026] Please see Figure 1 The reference electrode is a silver or silver chloride electrode, the counter electrode is a platinum electrode, and the working electrode is a gold or carbon electrode. The selected silver / silver chloride reference electrode has the characteristic of stable potential, the platinum counter electrode has strong conductivity and good chemical stability, and the gold or carbon working electrode has both good conductivity and biocompatibility. The combination of the three can form an efficient and stable electrode system, which improves the stability and accuracy of electrochemiluminescence detection.

[0027] The working principle of the electrochemiluminescence microfluidic chip for multiple tumor marker detection is as follows: First, the biological sample to be detected, such as blood or body fluid, is introduced into the microfluidic channel system through the sample inlet 2 on the substrate 1. After the sample enters, it flows through the shunt structure 3. The main channel of this symmetrical tree-like shunt structure 3 introduces the sample, and then through multiple branch channels of the same length and inner diameter, the sample is equally distributed into multiple parallel and equally spaced detection channels 4. Since the inner wall of each detection channel 4 is chemically coupled with specific capture probes 6 for different tumor markers, when the sample flows in the detection channel 4, the target tumor marker in the sample will specifically bind to the specific capture probe 6 in the corresponding detection channel 4, thereby achieving the target marker. The tumor markers are captured and enriched. After capture, the electrochemiluminescence detection unit starts working. The detection electrode group 7, which is independently set for each detection channel 4, is embedded in the substrate 1 and located below the detection channel 4. It consists of a working electrode, a reference electrode, and a counter electrode. The ruthenium bipyridine derivative layer on the surface of the working electrode generates an electrochemiluminescence signal under the action of an electrical signal. The intensity of this signal is related to the content of tumor markers captured in the detection channel 4. Finally, the conductive circuit embedded in the substrate 1 stably exports the electrochemiluminescence signals generated by each detection electrode group 7 to an external detection device through the signal acquisition interface 8. After the external device analyzes and processes the signal, it can obtain the content of tumor markers corresponding to each detection channel 4, thereby realizing the simultaneous and accurate detection of multiple tumor markers. The waste liquid after detection flows into the waste liquid pool 5 through the microfluidic channel system for collection, avoiding waste liquid contamination of the chip or affecting subsequent detection.

[0028] In the description of this invention, it should also be noted that, unless otherwise explicitly specified and limited, the terms "connected" and "linked" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium. Those skilled in the art can understand the specific meaning of the above terms in this invention based on the specific circumstances.

[0029] Finally, it should be noted that the above descriptions are merely preferred embodiments of the present invention and are not intended to limit the present invention. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art can still modify the technical solutions described in the foregoing embodiments or make equivalent substitutions for some of the technical features. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. An electrochemiluminescence microfluidic chip for multi-tumor marker detection, characterized in that, It includes a substrate (1) and a microfluidic channel system, an electrochemiluminescence detection unit and a signal acquisition interface (8) integrated on the substrate (1). The microfluidic channel system includes a sample inlet (2), a diversion structure (3), multiple parallel and equally spaced detection channels (4), and a waste liquid pool (5) connected in sequence. The diversion structure (3) includes a main channel and multiple branch channels integrally formed with the main channel. Each branch channel has the same length and inner diameter and is connected to each detection channel (4) in a one-to-one correspondence, used to divert the sample equally to each detection channel (4). The inner wall of each detection channel (4) is fixed with specific capture probes (6) for different tumor markers by chemical coupling. The electrochemiluminescence detection unit includes a detection electrode group (7) independently set for each detection channel (4). The detection electrode group (7) is embedded in the substrate (1) and located below the detection channel (4), and consists of a working electrode, a reference electrode and a counter electrode. The signal acquisition interface (8) is electrically connected to each detection electrode group (7) through conductive lines embedded in the substrate (1) to stably export the electrochemiluminescence signal to the external detection device. 2.The electrochemiluminescence microfluidic chip for multi-tumor marker detection according to claim 1, characterized in that, The substrate (1) is made of polydimethylsiloxane or glass, and the substrate (1) has grooves that match the microfluidic channel system. The inner wall of the grooves is hydrophilically treated. 3.The electrochemiluminescence microfluidic chip for multi-tumor marker detection according to claim 1, characterized in that, The surface of the working electrode is covered with an electroluminescent material layer by sputtering, and the electroluminescent material layer is a ruthenium bipyridine derivative layer. 4.The electrochemiluminescence microfluidic chip for multi-tumor marker detection according to claim 1, characterized in that, The diversion structure (3) is a symmetrical tree-shaped diversion channel, with the inner diameter of the main channel being 200-500μm and the inner diameter of the branch channels being 50-200μm.

5. The electrochemiluminescence microfluidic chip for multiple tumor marker detection according to claim 1, characterized in that, The inner diameter of each of the multiple detection channels (4) is the same, ranging from 50 to 500 μm, and the length difference between each detection channel (4) does not exceed 5%.

6. The electrochemiluminescence microfluidic chip for multiple tumor marker detection according to claim 1, characterized in that, The reference electrode is a silver or silver chloride electrode, the counter electrode is a platinum electrode, and the working electrode is a gold or carbon electrode.

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