KR20090093640A - Method of Fabricating CdSe/ZnS quantum dot and Glucose Sensor Using The Same - Google Patents

Abstract

A method for manufacturing of zinc oxide cadmium/zinc oxidase quantum is provided to easily bind with a bio material and improve the detection sensitivity of glucose concentration. A method for manufacturing cadmium selenide/zinc sulfide quantum dot comprises: a step of ionizing a cadmium to prepare a first solution; a step of ionizing selenium to make a second solution; a step of adding the second solution to make a third solution having cadmium selenide quantum dot; a step of ionizing zinc and sulfur to make a fourth solution; a step of adding the fourth solution in the third solution to prepare a fifth solution; a step of preparing sixth and seventh solution; and a step of adding n-hydroxysulfo-succinimide, 1-Ethyl-3-(3-dimethylaminopropyl) carbodiimide and glucose oxidase to fix the glucose oxidase in the cadmium selenide/zinc sulfide quantum dot.

Description

Cadmium selenide / zinc sulfide quantum dot manufacturing method and blood glucose sensor formed using the same {Method of Fabricating CdSe / ZnS quantum dot and Glucose Sensor Using The Same}

The present invention is a non-toxic, biochemically stable material, which is surface treated with a mercapto arsenic acid (MAA) material in zinc oxide, which has high value in biolabel and electrochemical applications. The present invention relates to a technique for easily preparing cadmium selenide / zinc sulfide quantum dots and forming a blood glucose sensor using the same.

Recently, the use of electrochemical biosensors for analyzing biological samples including blood in the pharmaceutical field is increasing.

A biosensor is a system that uses biological elements or mimics biological elements to obtain information from an object to be converted into useful signals that can be recognized, such as color, fluorescence, and electrical signals.

These biosensors focused mainly on blood glucose sensors with high clinical demand until just a few years ago. However, recent advances in molecular biology, nanotechnology (NT) and information and communication technology (IT) have led to the development of multi-sensor characteristics. The development of various sensors incorporating the PSA has been attempted, attracting much attention in terms of mass retrieval, multi-measurement or multi-diagnosis in addition to the purpose of simple biochemical aspects.

The most demanded fields for biosensors are known as the medical sector, which allows for free movement and immediate detection, which facilitates the use of high-risk drugs in the medical field and enables rapid medical care for critically ill patients. At the same time, demand is expected to continue to grow in the medical sector.

As applied to the medical field as described above may include a biosensor capable of selectively quantitative analysis of specific substances in biological samples, such as blood glucose, cholesterol, etc., and improved performance and development of new technologies around the world's manufacturers. Various studies are in progress.

The most commonly used biosensors to date include a glucose sensor for measuring blood glucose, which is described as an example of a glucose sensor.

Blood glucose sensors have been constantly developed to date based on the first sensor made by incorporating glucose oxidase, which oxidizes glucose, onto a polyacrylamide gel membrane and attaching it to the diaphragm sensor electrode.

Glucose oxidant, an enzyme used in blood glucose sensors, can be obtained easily and cheaply, and is more stable against pH, ionic strength, and temperature than other enzymes. It is widely used.

The analysis method of the above blood glucose sensor can be largely divided into photometeric method and electrochemical method. Both photometric and electrochemical methods basically use an oxidase which can react with glucose to oxidize glucose. do.

Photometric method quantifies the degree of color change by measuring the reflectance or transmittance of light using a photometer using a dye source that produces a color change when glucose is oxidized.

In contrast, electrochemistry measures glucose by measuring the electrons generated when oxygen or oxidized mediators are converted to hydrogen peroxide or reduced mediators when glucose is oxidized and then oxidized and returned to their original oxidized form in the form of current flowing through the electrodes. Quantify

Photometric methods generally require a longer measurement time, require a relatively large amount of blood, and are difficult to analyze important biological materials due to measurement errors due to turbidity of biological samples.

Therefore, recently, after forming an electrode, a screen reagent, a film adhesive method, or the like is used to expose an analyte to which only the analyte is fixed, and the remaining reagent is blocked to react with the measurement component in the sample. Electrochemical methods for quantitatively measuring a specific substance in a biological sample by applying and applying a constant potential after coating and fixing the exposed part and introducing a biological sample such as blood have been widely applied to a biosensor.

In the electrochemical method, a blood glucose sensor having a rectangular working electrode and a reference electrode formed on the insulating substrate and a recognition electrode formed on the other side of the insulating substrate is used.

Here, the recognition electrode is formed at a predetermined position on the test strip determined according to what substance is fixed by the reagent fixed across the working electrode and the reference electrode, and when the test strip is inserted into the biosensor measuring device, the biosensor measuring device By identifying the position of the recognition electrode on the test strip, it is possible to identify which material the test strip is intended to analyze.

In order to manufacture the test strip as described above, the electrode material is formed by sputtering electrode material on a predetermined region on the insulating substrate, and the reaction reacts with the measurement component in the sample while exposing only the part where the analysis reagent is fixed and blocking the remaining part. The reagents are applied and fixed to the exposed part.

Meanwhile, in the biosensor in which electrons are transferred through the working electrode as described above, current is generated for a predetermined time while electrons are generated through the reaction appearing at the working electrode after the sample is inputted, and the current signal is read by the measuring device to correspond to the sample. The components will be quantitatively analyzed.

In this case, when the same reaction occurs in the working electrode, the same current signal should be generated.

That is, even if the measurement using a plurality of test strips for the same sample of the same component (the same component to be measured) the reaction of the component and the reagent in the sample at the working electrode is the same, the same current signal should be output.

However, this should be the same for all the test strips manufactured, the area of the working electrode part (reaction part) to which the reagent is fixed, that is, the area of the working electrode to which the reagent is fixed (reaction part area of the working electrode) and the test strips. On the premise that

If the test strip is manufactured to have a difference in the area of the working electrode part (reaction part) in the reagent fixing part in the manufacturing process, the area of the reaction part between the sample and the reagent in the working electrode is different. Inevitably, a difference occurs in the current signal.

Therefore, in order to reduce the measurement error and increase the reliability, it is natural that the reaction area of the working electrode, that is, the area where the reagent is fixed on the working electrode must be the same area in all test strips without a slight error.

However, in the actual manufacturing process, it is difficult to produce the same area of the reaction part (fixed part) of the working electrode for each test strip without a minute error, thus reducing the process error as much as possible, thereby reducing the area of the reaction part in the working electrode. The focus is on reducing measurement errors as much as possible.

To this end, the area of the reagent fixing part exposed during screening or film-gluing for each test strip during the manufacturing process, especially the area where the reagent is fixed on the working electrode, is reduced to the same as possible by reducing the process error. However, there is still insufficient research or efforts to improve.

The present invention synthesizes cadmium selenide / zinc sulfide quantum dots in a state that can be easily combined with biomaterials using mercapto arsenic acid (MAA) as a surfactant without going through several steps, The method for preparing cadmium selenide / zinc sulfide quantum dots and the blood glucose sensor formed by using the same by fixing glucose oxidase on its surface to provide a blood glucose sensor more efficient than the conventional method of detecting glucose concentration by conventional electrochemistry Its purpose is to provide.

Cadmium selenide / zinc sulfide quantum dot manufacturing method according to the present invention comprises the steps of forming a first solution ionized cadmium, forming a second solution ionized selenium, the first solution in the heated state Adding a second solution to form a third solution comprising cadmium selenide quantum dots, cooling the third solution, forming a fourth solution ionized with zinc and sulfur, and Adding a fourth solution to the solution to form a fifth solution including cadmium selenide / zinc sulfide quantum dots having a zinc sulfide shell formed on the surface thereof, cooling the fifth solution while stirring the fifth solution; First washing the solution to form a sixth solution in which cadmium selenide / zinc sulfide quantum dots are dispersed in chloroform, and mercapto arsenic in the sixth solution. Replacing the surface ligands of the cadmium selenide / zinc sulfide quantum dots with mercapto arsenic acid (MAA) by adding a seed (Mercapto Arsenic Acid; MAA), and washing the sixth solution in a second And then forming a seventh solution in which cadmium selenide / zinc sulfide quantum dots are dispersed in chloroform, and mercapto arsenic acid (MAA) and n-hydroxysulfo-succinimide (Sulfo-NHS) in the seventh solution. ), 1-Ethyl-3- (3-dimethylaminopropyl) carbodiimide (EDC) and the addition of glucose oxidase, characterized in that it comprises the step of immobilizing the glucose oxidase on the cadmium selenide / zinc sulfide quantum dots.

In addition, the blood glucose sensor according to the present invention is manufactured by the above-described method, characterized in that formed using cadmium selenide / zinc sulfide quantum dots immobilized glucose oxidase.

The present invention provides a method for producing cadmium selenide / zinc sulfide quantum dots that can be well surface-treated with mercapto arsenic acid (MAA) and can be combined with biological materials without being replaced with biocompatible surfactants and cadmium thereof. By fixing glucose oxidase on selenide / zinc sulfide quantum dots and providing a glucose sensor for measuring glucose levels according to photoluminescence intensity, various problems in conventional photometry or electrochemical methods can be solved. It provides the effect of being able to detect other than biomaterials alone.

1A to 1C are schematic views showing a method for manufacturing cadmium selenide / zinc sulfide quantum dots according to the present invention.

Figure 2 is a photograph of a cadmium selenide / zinc sulfide quantum dot prepared by the embodiment according to the present invention by transmission electron microscope (TEM).

Figure 3 is a graph of the results of XRD analysis of cadmium selenide / zinc sulfide quantum dots prepared using the Examples and Comparative Examples according to the present invention.

Figure 4 is a graph of the results of UV-Visable spectrum analysis of cadmium selenide / zinc sulfide quantum dots prepared using the Examples and Comparative Examples according to the present invention.

5 and 6 are graphs showing the wavelength and photoluminescence according to the glucose concentration change.

Cadmium selenide / zinc sulfide (CdSe / ZnS) is a material with an electron band spacing of 1.74 eV and has been widely studied for its high value in biolabel and electrochemical applications. Most applications depend on the wavelength and intensity of the light emitted after light is irradiated on the cadmium selenide / zinc sulfide quantum dots. In addition, many studies are being conducted because the light can emit light in all visible light bands by using the quantum confinement effect as the powder becomes smaller. Here, the quantum confinement effect is a phenomenon that occurs in nano-powders smaller than the bore radius. In the case of a material larger than the bore radius, the wavelength of the material causes one refraction in the interval between the material and the outer interface. As the wavelength of the material is larger than the distance to the interface, it is smaller than the frequency of the wavelength. By this phenomenon, the wavelength of the material causes blue shift.

Cadmium selenide quantum dots are excellent in luminescence properties compared with zinc oxide and the like, but bioavailability has been limited because of heavy metals such as cadmium. However, when the shell is stacked with zinc sulfide, its luminescence properties are significantly increased and it is safe from cadmium, so it has many advantages when using cadmium selenide / zinc sulfide core-shell quantum dots. In the case of synthesizing cadmium selenide / zinc sulfide quantum dots with a core-shell, the luminescence properties of the cadmium selenide increased more than that of dangling bonds on the surface of the quantum dots. This is because the defect level generated by ultraviolet rays or heat is removed.

Specific details of the embodiments are included in the detailed description and the accompanying drawings.

Advantages and features of the present invention and methods for achieving them will be apparent with reference to the embodiments described below in detail with the accompanying drawings. However, the present invention is not limited to the embodiments disclosed below, but may be implemented in various different forms, only the present embodiments to make the disclosure of the present invention complete, and common knowledge in the art to which the present invention pertains. It is provided to fully inform the person having the scope of the invention, which is defined only by the scope of the claims. Like reference numerals refer to like elements throughout.

1A to 1C are schematic diagrams illustrating a method for preparing cadmium selenide / zinc sulfide quantum dots according to the present invention, wherein glucose oxidase is applied to cadmium selenide / zinc sulfide quantum dots surface-treated with mercaptoacetic acid (MAA). The process of immobilization is shown.

Referring to Figure 1a, the cadmium oxide source and staric acid (stearic acid) is put in a flask and heated to a temperature of 100 ~ 150 ℃ in a nitrogen atmosphere to obtain a clear solution.

Next, trioctylphosphine oxide and nuxadecylamine are added to the transparent solution formed in the flask as a stabilizer in a ratio of 1: 1 and reheated to a temperature of 250 to 310 ° C. to form a first solution in which cadmium is ionized.

Next, the selenium source and the tributylphosphine solution are mixed to make 1M, and then the selenium source is dissolved using ultrasonic to form a second solution.

Next, a second solution is injected into the first solution heated at 250 to 310 ° C. using a syringe, and a stirring process is performed to form cadmium selenide quantum dots in the solution. At this time, the injection speed using a syringe is preferably within 2 seconds.

Next, a solution containing cadmium selenide quantum dots is called a third solution, and the third solution is cooled to a temperature of 200 to 250 ° C.

Next, a fourth solution in which the zinc and sulfur sources are ionized in a tributylphosphine solution is prepared separately from the third solution.

Next, the fourth solution is injected into the third solution so that an anti-zinc shell is formed on the surface of the cadmium selenide quantum dot. At this time, the rate of injecting the fourth solution is preferably injected as slowly as possible at the rate at which the zinc sulfide powder is not synthesized and only the shell is formed on the surface of the cadmium selenide quantum dot.

Subsequently, a solution containing cadmium selenide / zinc sulfide quantum dots is called a fifth solution, and the fifth solution is cooled to a temperature of 100 to 130 ° C., followed by stirring for 1 hour 30 to 2 hours.

The cadmium selenide / zinc sulfide quantum dot 220 formed as described above includes a zinc sulfide (ZnS) shell 120 formed on the surface of the cadmium selenide (CdSe) quantum dot 100. At this time, the surface of the zinc sulfide (ZnS) shell 120 includes a trioctylphosphine oxide (TOPO) ligand.

FIG. 1B shows a shape in which mercaptoacetic acid (MAA) is substituted for cadmium selenide / zinc sulfide quantum dots 150.

To replace the mercapto acetic acid (MAA), a washing process is first performed.

A solution of chloroform and methanol in a ratio of 1: 1 is added to the fifth solution, and the cadmium selenide / zinc sulfide quantum dot 200 is washed using a centrifuge to sink into powder in the solution. This process is performed 2 to 5 times more to wash the cadmium selenide / zinc sulfide quantum dot 200 and to disperse the cadmium selenide / zinc sulfide quantum dot 200 in chloroform or toluene solution.

Next, a solution in which the washed cadmium selenide / zinc sulfide quantum dot 200 is mixed is referred to as a sixth solution, and to the sixth solution, mercapto arsenic acid (MAA) is added. At this time, the ratio of cadmium selenide / zinc sulfide quantum dots and mercapto arsenic acid (MAA) is 1: 3 and stirred for 2 to 5 hours.

Here, the reason why the mercaptoacetic acid (MAA) is bonded to the surface of zinc sulfide is identified by two mechanisms.

One is a dehydration of a hydroxyl group (-OH) on a zinc sulfide surface with a carboxyl group (-COOH) in a mercaptoacetic acid (MAA) bond, and the other is on a zinc sulfide surface. This is because the zinc (Zn) atom and sulfur (S) in the thiloate (SH) group in the mercaptoacetic acid (MAA) are very familiar.

For these two reasons, the cadmium selenide / zinc sulfide quantum dot 200 in a well-substituted form is formed on the surface of the mercaptoacetic acid (MAA) zinc sulfide.

Figure 1c shows that the glucose oxidase is immobilized on the cadmium selenide / zinc sulfide quantum dots.

In order to fix the glucose oxidase, the sixth solution was washed 2 to 5 times using chloroform and methanol as described above, and then the seventh solution in which the cadmium selenide / zinc sulfide quantum dot 200 was dispersed in chloroform or toluene. To form.

Next, mercaptoacetic acid (MAA), n-hydroxysulfo-succinimide (Sulfo-NHS), 1-Ethyl-3 (3-dimethylaminopropyl) carbodiimide (EDC), and glucose oxidase were mixed in a seventh solution. Activate the carboxyl group on the surface of the amide / zinc sulfide quantum dot (200) and induce a coupling (coupling) reaction with the amine group on the surface of the glucose oxidase to form a glucose oxidase of the cadmium selenide / zinc sulfide quantum dot (200) Immobilize on the surface.

Finally, the washing process as described above is further performed to completely remove impurities remaining around the cadmium selenide / zinc sulfide quantum dots 200 to which glucose oxidase is immobilized.

Prepared as described above to form cadmium selenide / zinc sulfide quantum dots. Since the glucose oxidase was simply immobilized by mercaptoacetic acid (MAA), the sugar was added to the solution in a certain concentration in a buffer solution containing cadmium selenide / zinc sulfide quantum dots to which glucose oxidase was immobilized. Depending on the concentration of sugars, optical changes occur in cadmium selenide / zinc sulfide quantum dots. This optical change is called photoluminescence, and by measuring the change in the photoluminescence, the sugar level can be accurately measured.

Here, photoluminescence is also called photoluminescence, and a luminescence material absorbs energy such as light, electricity, and radiation into an excited state, and when it returns to the ground state, it absorbs energy. It refers to the phenomenon of emitting.

Photoluminescence is a luminescence generated by excitation by light, and generally emits light having a wavelength equal to or longer than that of irradiated light (irradiation light). In some cases, the light emitting center absorbs light and is excited and emits light. In some cases, a carrier generated by the absorption of light is captured by the light emitting center and emits light. Therefore, blood glucose can be measured using the photoluminescence spectrum which measures such photoluminescence.

Hereinafter, specific examples for the preparation of cadmium selenide / zinc sulfide quantum dots and a method for fixing glucose oxidase according to embodiments of the present invention will be presented. However, the content not described herein is omitted because it can be inferred technically sufficient by those skilled in the art.

EXAMPLE

Cadmium oxide and steric acid are mixed and heated to 150 ° C. in a nitrogen atmosphere, and trioctylphosphine oxide and nuxadecylamine are mixed in a 1: 1 ratio to form a solution heated to 300 ° C. .

Next, selenium and tributylphosphine are mixed to prepare a selenium ionized solution separately, and the selenium ionization solution is added to the cadmium ionization solution heated to 300 ° C. At this time, cadmium selenide quantum dots are formed in the solution.

Next, zinc and sulfur ionized solutions are prepared separately, and the solution is dropped dropwise into the buffer solution in which the cadmium selenide quantum dots are dispersed so that zinc sulfide shells are deposited on the cadmium selenide quantum dot surface.

Then, the solution containing the cadmium selenide / zinc sulfide quantum dot is cooled to 110 ℃ and stirred for 90 minutes to increase the crystallinity.

Next, after two to five washing steps, the cadmium selenide / zinc sulfide quantum dot powder is dispersed in chloroform.

Subsequently, the surface ligands of cadmium selenide / zinc sulfide quantum dots were replaced with mercaptoacetic acid (MAA), followed by n-hydroxysulfo-succinimide (Sulfo-NHS), 1-Ethyl-3 (3-dimethylaminopropyl) carbodiimide (EDC) is used to immobilize glucose oxidase on the surface of cadmium selenide / zinc sulfide quantum dots.

Next, the cadmium selenide / zinc sulfide quantum dots immobilized with glucose oxidase are washed and dispersed in chloroform, and sugar is added to the solution to measure the increase in photoluminescence.

[Comparative Example]

The same procedure as in the above example was performed except that mercaptoacetic acid (MAA) was not used before glucose oxidase binding.

[Characteristic Analysis]

Prepared as described above is subjected to UV-visible, XRD, PL analysis or transmission electron microscopy (TEM) analysis for the cadmium selenide / zinc sulfide quantum dots immobilized glucose oxidase.

[Feature Analysis Results]

2 is a photograph of a cadmium selenide / zinc sulfide quantum dot prepared by an embodiment according to the present invention with a transmission electron microscope (TEM).

Referring to Figure 2, it can be seen that the size of the prepared cadmium selenide / zinc sulfide quantum dot is about 5nm and the grid point is clearly visible.

Therefore, it can be seen that the degree of crystallinity is very high. Cadmium selenide / zinc sulfide quantum dots are all spherical in shape.

Figure 3 is a graph of the results of XRD analysis of cadmium selenide / zinc sulfide quantum dots prepared using the Examples and Comparative Examples according to the present invention.

Referring to FIG. 3, it can be seen that the cadmium selenide (CdSe) quantum dots prepared according to the present invention are manufactured to a nano size and overlap with adjacent peaks. This indicates that a large number of surface defects occur in the cadmium selenide (CdSe) is reduced crystallinity.

However, it can be seen that the zinc sulfide (ZnS) shell of cadmium selenide / zinc sulfide (CdSe / ZnS) exerts a compressive stress on the cadmium selenide (CdSe) quantum dot to move the peak to the right. This pick has a crystalline hexagonal wurtzite phase.

Figure 4 is a graph of the results of UV-Visable spectrum analysis of cadmium selenide / zinc sulfide quantum dots prepared using the Examples and Comparative Examples according to the present invention.

Referring to FIG. 4, when a zinc sulfide (ZnS) shell is coated on a cadmium selenide (CdSe) quantum dot, the wavelength of the wavelength is increased, and the absorption peak is shifted to the right.

Here, when the ligand is substituted with mercapto acetic acid (MAA), the same peak as the cadmium selenide / zinc sulfide quantum dot having trioctylphosphine oxide as the ligand is used for cadmium selenide / sulfide during the substitution process. It can be seen that the zinc quantum dots do not aggregate together.

When the blood glucose sensor is manufactured using the cadmium selenide / zinc sulfide quantum dots formed as described above, it is as follows.

First, in order to measure photoluminescence, a quartz cell (1 × 1 cm) made of quartz is prepared on a slope, and 1.5-2.5 ml of the solution prepared according to the embodiment is added to the cell.

Next, the intensity of the pick is measured while adding 0.01 to 0.02 ml of a small amount of glucose to the solution.

5 and 6 are graphs showing wavelengths and photoluminescence according to glucose concentration change.

5 and 6, it can be seen that the electron generated by the oxidation of glucose by glucose oxidase enters the cadmium selenide / zinc sulfide quantum dot and the photoluminescence increases with glucose concentration. This allows measurement of glucose concentration.

Here, the reason why the strength of PL increases with the amount of glucose is as follows.

When glucose (D-glucose) enters a solvent containing cadmium selenide / zinc sulfide quantum dots to which glucose oxidase (GOx) is immobilized, two protons and electrons are generated to riboflavin adenine dinucleotide (FAD), a coenzyme of glucose oxidant. The two protons again react as follows:

The two electrons pass through riboflavin adenine dinucleotide (FAD) to the cadmium selenide / zinc sulfide quantum dot, which further increases the photoluminescence as the electron moves from the conduction band to the valence band.

Although the embodiments of the present invention have been described above with reference to the accompanying drawings, the present invention is not limited to the above embodiments but may be manufactured in various forms, and having ordinary skill in the art to which the present invention pertains. It will be understood by those skilled in the art that the present invention may be embodied in other specific forms without changing the technical spirit or essential features of the present invention. Therefore, it should be understood that the embodiments described above are exemplary in all respects and not restrictive.

Claims (13)

Forming a first solution in which cadmium is ionized; Forming a second solution of ionized selenium; Adding the second solution while the first solution is heated to form a third solution including cadmium selenide quantum dots; Cooling the third solution; Forming a fourth solution of ionized zinc and sulfur; Adding a fourth solution to the third solution to form a fifth solution including cadmium selenide / zinc sulfide quantum dots having a zinc sulfide shell formed on a surface thereof; Cooling the fifth solution while stirring; First washing the fifth solution to form a sixth solution in which cadmium selenide / zinc sulfide quantum dots are dispersed in a buffer solution; Adding a mercapto arsenic acid (MAA) to the sixth solution to replace the surface ligands of the cadmium selenide / zinc sulfide quantum dots with mercapto arsenic acid (MAA); Forming a seventh solution in which the cadmium selenide / zinc sulfide quantum dots are dispersed in a buffer solution after the second washing of the sixth solution; To the seventh solution, mercapto arsenic acid (MAA), n-hydroxysulfo-succinimide (Sulfo-NHS), 1-Ethyl-3- (3-dimethylaminopropyl) carbodiimide (EDC) and glucose oxidase were added. Cadmium selenide / zinc sulfide quantum dot production method comprising the step of immobilizing glucose oxidase on the cadmium selenide / zinc sulfide quantum dot. The method of claim 1, Forming the first solution Placing a cadmium oxide source and staric acid into the flask and heating to a temperature of 100 to 150 ° C. in a nitrogen atmosphere; And Cadmium selenide / zinc sulfide quantum dot manufacturing method characterized in that it further comprises the step of adding trioctylphosphine oxide and nuxadecylamine in a ratio of 1: 1 and reheating to a temperature of 250 ~ 310 ℃. The method of claim 1, Forming the second solution Mixing selenium source and tributylphosphine solution to 1M; And A method of manufacturing cadmium selenide / zinc sulfide quantum dots, further comprising dissolving the selenium source using ultrasonic. The method of claim 1, Forming the third solution Cadmium selenide / characterized in that it further comprises the step of injecting the second solution into the first solution heated to a temperature of 250 ~ 310 ℃ using a syringe, and performing a stirring process to form cadmium selenide quantum dots Zinc sulfide quantum dot production method. The method of claim 1, Cooling the third solution is a cadmium selenide / zinc sulfide quantum dot manufacturing method characterized in that performed to a temperature of 200 ~ 250 ℃. The method of claim 1, Forming the fourth solution is A method for producing cadmium selenide / zinc sulfide quantum dots characterized by ionizing a zinc and sulfur source in a tributylphosphine solution. The method of claim 1, Forming the fifth solution Cadmium selenide / zinc sulfide quantum dot manufacturing method characterized in that the fourth solution is injected into the third solution to form a zinc zinc shell on the cadmium selenide quantum dot surface. The method of claim 1, The cooling of the fifth solution while stirring is performed to 100 to 130 ° C., and a cadmium selenide / zinc sulfide quantum dot manufacturing method is performed for 1 hour 30 to 2 hours. The method of claim 1, The first washing step is to put the fifth solution in a mixture of chloroform and methanol in a ratio of 1: 1 and to obtain a powder while washing the cadmium selenide / zinc sulfide quantum dots using a centrifuge Cadmium selenide / zinc sulfide quantum dot manufacturing method characterized in that for performing 2 to 5 times. The method of claim 1, The process of adding the mercapto arsenic acid (MAA) to the sixth solution is the cadmium selenide / zinc sulfide quantum dots and mercapto arsenic acid (MAA) dispersed in the sixth solution. The cadmium selenide / zinc sulfide quantum dot production method characterized in that the ratio of 1: 3 and further performing a step of stirring for 2 to 5 hours. The method of claim 1, The second washing step is to put the sixth solution in a mixture of chloroform and methanol in a ratio of 1: 1 and to obtain a powder while washing the cadmium selenide / zinc sulfide quantum dots using a centrifuge Cadmium selenide / zinc sulfide quantum dot manufacturing method characterized in that for performing 2 to 5 times. The method of claim 1, Cadmium selenide / zinc sulfide quantum dot production method characterized in that the buffer solution using chloroform or toluene. The glucose sensor according to claim 1, wherein the glucose oxidase is formed using immobilized cadmium selenide / zinc sulfide quantum dots.