TW201623955A - A biosensor with structure of micro chamber - Google Patents

Abstract

This invention is related to a biosensor with structure of micro chamber which makes less liquid sample volume required and rapid detection of enzyme based reaction. The biosensor comprises a micro chamber closed to electrode of biosensor fulfilled with porous structure, in which the enzyme was immobilized homogeneously. The space of micro chamber was assembled by biosensor substrate with electrodes, isolation layer, porous matters and cover layer with sampling hole and vent hole. Introducing the porous structure into micro chamber will enhance the wetting of liquid sample on electrode and decrease sample volume needed. Also, the dispersed enzyme in porous structure make the higher rate for catalytic reaction. Thus, the deviation and delay of biosensor detection could be minimized due to the less mass transfer resistance between electrode, enzyme and target chemicals.

Description

Biosensor with microcavity structure

The present invention relates to a biosensor having a microcavity structure, in particular, when a biosensor is used to measure a concentration of a test substance in a liquid sample through an enzyme catalytic reaction, a biosensor can be used. The microcavity structure formed by the inner structure and the porous structure filled with the uniformly dispersed enzyme in the microcavity rapidly adsorb and diffuse the liquid sample of the sample to the microcavity, thereby improving the contact chance of the enzyme and the object to be tested, and The volume required for filling in the microcavity is reduced, and the reaction electrode can be quickly contacted, thereby reducing the diffusion mass transfer resistance of the electrochemical reaction, thereby improving the detection accuracy of the biosensor and shortening the measurement time.

Biosensors are widely used in environmental sanitation and medical treatment, such as in medical care, and are quite convenient for various blood indicators of patients, such as blood sugar, uric acid, and cholesterol. At present, in addition to the repetitive use of sensors commonly used in medical institutions or inspection agencies, disposable disposable biosensors for commercial applications are also very popular. In environmental or food testing, biosensors can also be used to analyze and detect pesticide residues and heavy metal wastewater concentrations.

Conventional biosensor structures are mostly simple printed electrodes and multiple layers. The substrate is composed of a linear microchannel and an electrochemical bioreactor region. Although the measured values of the body fluid can be quickly and conveniently obtained, the blood is generally used, but in practical applications, the volume of blood is small. The detection is still limited by the microscopic flow and mass transfer resistance of the small finite reaction material (less than 3 μl, μL) in the local reaction interval, which leads to the error of the measurement results.

According to the experiments and experience learned by biosensors, in the case of blood detection, in the past, the biosensor was designed to immobilize the enzyme on the surface of the working electrode, and the bio-enzyme was adhered to the special polymer material formula. Above the conductive material, through the micro-flow channel and a porous film or microstructure that specifically reduces the Hematocrit effect (Hct) in the blood, the accuracy of detection of cholesterol or blood sugar in the blood is improved, such as the Republic of China patent (I359948) And the structure of the test paper for the exclusion of red blood cell filtration disclosed in the Republic of China patent (I464396), wherein the filtration effect of the porous material is mainly used to filter the related substances affecting the blood volume ratio in the blood, through gravity filtration or vacuum extraction. In order to carry out its measurement requirements.

However, regardless of whether or not the blood is pretreated or not pretreated, the biosensor structure must transport the blood to the electrode surface through the microchannel structure, and then fix the electrode surface with the polymer package. The enzyme layer is first dissolved in blood to react with the dissolved blood sugar or cholesterol in the blood, and the enzyme utilization rate is poor. Such biosensors must be designed to consume more blood, usually requiring a blood volume of 3.0uL to 10.0uL, which is more versatile in operation. In addition, in order to use porous materials to exclude related substances that affect the blood cell volume ratio in the blood, it is necessary to overcome the porous material to the blood. Filtration resistance requires relatively more overall measurement time, which also causes inconvenience in operating biosensor measurement and inefficient operation.

In order to overcome the accuracy and time spent measuring the traditional biosensor through the micro flow channel and the porous material, and reduce the demand of the liquid to be tested, and improve the efficiency of the enzyme reaction, the present invention provides a living organism. a sensor for detecting a substance to be tested in a liquid sample, the biosensor comprising: a biosensor substrate, a biosensor signal connection line, a reaction electrode, an insulation layer, and an upper cover The layer, an enzyme fixed porous layer, a drop inlet, an exhaust port and a microcavity. The reaction electrode and the biosensor signal connection line are formed on the biosensor substrate, and the reaction electrode is composed of a working electrode and an auxiliary electrode. The insulating layer forms a container space having a height around the position of the reaction electrode, and exposes it at one end of the biosensor connection line to facilitate contact with the connector. The enzyme fixed porous layer is fixed on one side of the upper cap layer having a drip inlet, and is fixedly stacked with the vent hole, and the vent is located on either side of the drip inlet, and can overlap with the enzyme fixed porous layer. It also does not overlap. The upper cap layer which fixes the immobilized porous layer of the enzyme is bonded to the insulating layer by one side of the porous layer of the immobilized enzyme, and further forms a container space having a height around the position of the reaction electrode by the insulating layer and the foregoing The upper cover layer is surrounded by the aforementioned microcavity space occupied by the enzyme fixed porous layer portion. The enzyme fixed porous layer is disposed on the upper edge of the microcavity, wherein the liquid sample introduced through the drip inlet at the upper cap layer immediately enters the adjacent fixed layer of the enzyme and directly starts to The enzyme is subjected to a catalytic reaction, and at the same time, the liquid sample rapidly penetrates the immobilized porous layer of the enzyme through capillary action, and then wets the surface of the reaction electrode immediately adjacent to the electrochemical sensing reaction.

In order to achieve the above-mentioned advantages of overcoming the traditional biosensor filtering through the microchannel and the porous material, the accuracy and time of the measurement are reduced, the demand of the liquid to be tested is reduced, and the efficiency of the enzyme reaction is improved, and the present invention is further improved. In a specific embodiment, the microcavity space of the biosensor having the microcavity structure may be occupied by the filled enzyme fixed porous layer.

In an embodiment of the present invention, the enzyme-immobilized porous layer of the biosensor having a microcavity structure may be composed of two or more pore structure stacks, and different types of biological enzyme substances are respectively fixed.

In an embodiment of the present invention, the enzyme-immobilized porous layer of the biosensor having a microcavity structure may be simultaneously fixed in the porous structure by two or more kinds of biological enzymes.

In an embodiment of the present invention, the enzyme-immobilized porous layer of the biosensor having a microcavity structure may form two or more regions independently on the surface of the reaction electrode, and two or more bio-enzymes may be simultaneously or individually fixed to each other. In the porous structure, the sensor layer can be assembled by fitting a cover layer having two or more different sizes and sizes.

In an embodiment of the invention, the aforementioned biosensor having a microcavity structure can be used for electrochemical detection.

In the embodiment of the present invention, the aforementioned creature having a microcavity structure The sensor can be used for optical detection, and the drop inlet provided in the upper cover layer can be used as a signal detection position for optical detection.

10‧‧‧Biosensor substrate

11‧‧‧Biosensor signal connection line

12‧‧‧Reaction electrode

13‧‧‧Insulation

14‧‧‧Upper cover

15‧‧‧Enzyme fixed porous layer

16‧‧‧Liquid samples

17‧‧‧Drip entrance

18‧‧‧Exhaust port

19‧‧‧Microcavity

Figure 1 is a schematic cross-sectional view of a biosensor having a microcavity structure of the present invention.

The above and other technical contents, features and advantages of the present invention will be apparent from the following detailed description of the preferred embodiments.

The present invention relates to a biosensor having a microcavity structure, in particular, when a biosensor is used to measure a concentration of a sample to be tested in a liquid sample by an enzyme catalytic reaction, the biosensor can be used. The microcavity structure formed by the inner structure and the porous structure filled with the uniformly dispersed enzyme in the microcavity rapidly adsorb and diffuse the liquid sample of the sample to the microcavity, thereby improving the contact chance of the enzyme and the object to be tested, and The volume required for filling in the microcavity is reduced, and the reaction electrode can be quickly contacted, thereby reducing the diffusion mass transfer resistance of the electrochemical reaction, thereby improving the detection accuracy of the biosensor and shortening the measurement time. In order to obtain an effective and accurate description, an implementation case is presented below for explanation. Please refer to FIG. 1, which is a designated representative diagram of the present invention. The present invention provides a biosensor for detecting a substance to be tested in a liquid sample 16, the biosensor comprising: a biosensor substrate 10, a raw The sensor signal connection line 11, the reaction electrode 12, the insulating layer 13, the upper cap layer 14, the enzyme-immobilized porous layer 15, the drip inlet 17, the exhaust port 18, and a microcavity 19. A biosensor having a microcavity 19 structure is formed on the biosensor substrate 10 by a reaction electrode 12 and a biosensor signal connection line 11, and the reaction electrode 12 is composed of a working electrode and an auxiliary electrode. Composed of. The foregoing insulating layer 13 forms a container space having a height around the position of the reaction electrode 12, and exposes it at one end of the biosensor signal connecting line 11 to facilitate contact with the connector. The enzyme-immobilized porous layer 15 is fixed to one side of the upper cap layer 14 having the drip inlet 17 and is fixedly stacked with the vent hole 18, and the vent 18 is located on either side of the drip inlet 17 to be fixed with the enzyme. The porous layers 15 may or may not overlap. The upper layer 14 of the enzyme-immobilized porous layer 15 is adhered to one side of the insulating porous layer 15 and the upper side of the insulating layer 13 on the biosensor substrate 10, and further formed with the insulating layer 13 at the reaction electrode 12. A space surrounded by a container space and an upper cover layer 14 is formed around the position, and the inside is surrounded by a portion of the microcavity 19 occupied by the enzyme-immobilized porous layer 15. The enzyme-immobilized porous layer 15 is disposed on the upper edge of the microcavity 19, wherein the liquid sample 16 introduced through the drip inlet 17 located in the upper cap layer 14 immediately enters the immediately adjacent enzyme-fixed porous layer 15 and directly starts with the enzyme. The catalytic reaction, at the same time, the liquid sample 16 also rapidly penetrates the enzyme-fixed porous layer 15 located in the space of the microcavity 19 by capillary action, and then wets the surface of the reaction electrode 12 immediately adjacent to the electrochemical sensing reaction.

According to still another embodiment of the present invention, the enzyme-immobilized porous layer 15 of the biosensor having the microcavity 19 structure may be composed of a stack of two or more pore structures, and different types of biological enzyme substances are separately immobilized.

According to still another embodiment of the present invention, the enzyme-immobilized porous layer 15 of the biosensor having the microcavity 19 structure can be simultaneously immobilized in the structure of the single enzyme porous layer 15 by two or more kinds of bio-enzymes.

According to still another embodiment of the present invention, the enzyme-immobilized porous layer 15 of the biosensor having the microcavity 19 structure can form two or more regions independently on the surface of the reaction electrode 12, and two or more kinds of biological enzymes simultaneously or Individually fixed in the structure of the enzyme-immobilized porous layer 15, and the cover layer 14 having the drop inlets 17 having two or more different sizes and sizes can be used for the structure of the biosensor. .

The spirit of the structural design and technical features of the present invention can be explained in detail by the above description of the embodiments, and the preferred embodiments disclosed above are not intended to limit the scope of the present invention, and if there are other changes or equivalences. The arrangements are all within the scope of this creative work. Therefore, the scope of patents applied for by this creation should be interpreted broadly in accordance with the above description and cover all possible changes and equivalence arrangements.

10‧‧‧Biosensor substrate

11‧‧‧Biosensor signal connection line

12‧‧‧Reaction electrode

13‧‧‧Insulation

14‧‧‧Upper cover

15‧‧‧Enzyme fixed porous layer

16‧‧‧Liquid samples

17‧‧‧Drip entrance

18‧‧‧Exhaust port

19‧‧‧Microcavity

Claims (10)

A biosensor having a microcavity structure, comprising a biosensor substrate; a biosensor signal connection line and a reaction electrode connected to each other, which is located on one side surface of the biosensor substrate An insulating layer is fixed on the same side surface of the biosensor substrate to which the biosensor signal connecting line and the reaction electrode are attached by partial covering, so that the surface is located around the reactive electrode region to form an The height of the container space, while exposing the part of the biosensor signal connection line, in order to facilitate the electronic signal transmission with the external connector; an upper cover layer has a hole structure for the liquid sample drop inlet and the exhaust port to facilitate the liquid The pressure balance of the sample when it is dropped into the biosensor, and the exhaust port is located on either side of the drop inlet; the enzyme fixed porous layer is a material layer for attaching the bioenzyme component to the inner pore, located on one side of the upper cap layer The surface is fixed to the upper cover layer with a relative position of the drop inlet, and the area of the enzyme fixed porous layer may cover the position extending to the vent hole; a microcavity Above the reaction electrode, a micro-space composed of a biosensor substrate, an insulating layer and an upper cap layer is stacked, and the enzyme fixed porous layer is bonded and fixed to one side of the cap layer and the insulating layer is bonded to each other. Further, an insulating layer is formed around the position of the reaction electrode to form a height of the container space and the upper cap layer, and the inside is occupied by the microcavity space occupied by the enzyme fixed porous layer; the enzyme fixed porous layer is disposed in the microcavity The upper edge, through the drop inlet located on the other side surface of the upper cap layer, introduces the liquid sample to be measured, and the liquid sample can immediately enter the enzyme fixed porous layer adjacent to the upper cap layer, and directly start catalytic reaction with the enzyme, and at the same time, Liquid samples are also quickly worn through capillary action The porous layer is fixed by permeabilizing, and the surface of the immediately adjacent reaction electrode is wetted and electrochemically sensed. A biosensor having a microcavity structure as claimed in claim 1, wherein the reaction electrode may comprise a combination of a working electrode, an auxiliary electrode and a reference electrode. A biosensor having a microcavity structure according to claim 1, wherein the composition of the enzyme-immobilized porous layer may comprise a metal, a non-metal, a polymer, a fiber, a composite film or the like having an open porous cavity structure. A biosensor having a microcavity structure according to claim 1, wherein the bioenzyme species to which the enzyme-immobilized porous layer is adsorbed and fixed may contain more than one type. A biosensor having a microcavity structure according to claim 1, wherein the enzyme fixed porous layer may be stacked or arranged in a porous material structure of one or more different pore diameters, and may be fixed separately under different hole diameter conditions. Kinds of biological enzymes. A biosensor having a microcavity structure according to claim 1, wherein the enzyme-immobilized porous layer may be a stacked material or a combination of a hydrophilic material or a hydrophobic material. A biosensor having a microcavity structure as claimed in claim 1, wherein the number of the open holes of the upper cap layer as the drip inlet and the exhaust port may be one or more. A biosensor having a microcavity structure according to claim 1, wherein the open pore of the upper cap layer can simultaneously serve as a liquid sample drip inlet of an electrochemical biosensor and color development of an optical color biosensor window. A biosensor having a microcavity structure as claimed in claim 1, wherein the microcavity is constructed such that the partial volume is filled with the enzyme fixed porous layer or completely filled with the enzyme fixed porous layer. A biosensor having a microcavity structure according to claim 1, wherein the microcavity is formed on the biosensor by a quantity of more than one micro space, and each micro space can flow liquid to each other, or can be independent The existence of a closed.