KR102089177B1 - Chemiluminescence Detection Method for Determination of Metal Ions - Google Patents

Abstract

The present invention relates to a method and apparatus for detecting chemiluminescence that increases analytical sensitivity by minimizing a decrease in sensitivity by reacting during a process in which a sample, a chemiluminescent body, and an oxidizing agent are transferred to a reactor.
The chemiluminescence detection method and apparatus of the present invention separates a sample containing a metal ion, a chemiluminescent body and an oxidizing agent into a segmented material and supplies them to the reactor, thereby preventing the chemiluminescence reaction from proceeding before reaching the reactor. Therefore, the present invention can minimize the decrease in sensitivity by reacting during the process in which the reagents and the sample are transferred to the reactor, so that the analysis sensitivity can be increased compared to the conventional device.
In addition, the present invention induces the mixing of the sample with the chelating agent EDTA (ethylenediaminetetraacetic acid), which is a chelating agent, prior to being introduced into the reactor to selectively remove the interfering metal, thereby more accurately measuring the concentration of chromium trivalent that contributed to the chemiluminescence reaction.
In addition, the present invention does not require a mixing channel for mixing a sample and a reagent, and a device can be configured as a common channel between one pump and a valve.

Description

Chemiluminescence Detection Method for Determination of Metal Ions}

The present invention relates to a method and apparatus for detecting chemiluminescence, and more particularly, to a method and apparatus for chemiluminescence detection by increasing the analytical sensitivity by minimizing a decrease in sensitivity by reacting during a process in which a sample, a chemiluminescent body and an oxidizing agent are transferred to a reactor. It is about.

Along with rapid industrial development, the urban concentration of the population and the massive release of chemical hazardous materials pose a serious threat to nature and ecosystems. Harmful heavy metals such as arsenic (As), lead (Pb), cadmium (Cd), chromium (Cr), selenium (Se), and mercury (Hg), which have a detrimental effect on living organisms, do not decompose into water or become stable compounds. It remains mixed and contaminates water quality and soil. The underwater animals and plants exposed to the harmful heavy metals are quickly discharged out of the body because they form an organic complex that does not decompose by combining with the in vivo substances when it is absorbed and transported into the body through various foods and is absorbed into the body according to the food chain. It is not a substance with strong properties that accumulate in organs or bones, such as liver and kidneys, and may cause health disorders even at low concentrations. In particular, heavy metals accumulated in the body are not easily discharged, so the resulting disease is difficult to heal.

Heavy metal, a hazardous substance in water, has emerged as the core of water quality management for the improvement of quality of life and sustainable development. Methods for measuring the concentration of heavy metals in water include an atomic spectroscopy method in which a sample is vaporized using a flame or an inductively coupled plasma (atomic) to measure the concentration of atoms, and ultraviolet-visible absorbance, fluorescence, and chemiluminescence methods. For effective water quality management against heavy metal pollution in water, it is desirable to install and monitor automatic measuring devices in many places. In terms of field application, measuring devices using atomic spectroscopy are large, expensive, and are not suitable for monitoring. The chemiluminescence method is a method that measures the intensity of light generated by a chemical reaction, and the device is simple and can analyze heavy metals in a wide range of concentrations with high sensitivity.

Chemiluminescence method capable of analyzing heavy metals in water (chromium, copper, nickel, cobalt, iron, tin, magnesium, calcium, zinc, barium, strontium, vananium, lead, manganese, aluminum, silver, mercury or cadmium ions) Is as in Formula 1 below.

Under basic conditions, luminol (3-aminophthalhydrazide), a chemiluminescent agent, is oxidized by hydrogen peroxide (oxidant) to emit light at 425 nm. At this time, the metal ions can participate in the luminol oxidation reaction to measure chemiluminescence in a short time within 10 seconds, and quantify using the proportion of the metal ions (M, n: oxidation value) contained in the sample. This is possible.

Registered Patent No. 10-1466301 (Pohang University of Science and Technology) contains microfluidic chips for detecting chemiluminescence by continuously injecting samples, reducing agents, and chemiluminescent reagents (luminol, hydrogen peroxide) necessary for chemiluminescence reaction into each inlet. It relates to a detection device. The sample and the reducing agent, and luminol and hydrogen peroxide are mixed in a reduction channel and a reagent mixing channel, respectively, and then met in a detection channel to perform a chemiluminescence reaction. The registration patent discloses a chromium detection device that minimizes the loss of chemiluminescence generated in the reagent mixing channel by varying the length of the reduction channel and the reagent mixing channel (patent submitted by the present inventor). However, there is a need for a plurality of pumps or multi-channel pumps for simultaneously injecting a solution used for the reaction and improving the decrease in sensitivity due to the occurrence of chemiluminescence by mixing between chemiluminescent reagents in the reagent mixing channel.

The present invention provides a method and apparatus for preventing a sample containing a heavy metal, a chemiluminescent material, and an oxidizing agent from reacting during a process of being transferred to a reactor.

The present invention provides a method and apparatus capable of selectively removing only interfering metals in a sample before the sample and the chemiluminescent reagent are mixed.

The present invention provides a method and apparatus for measuring the concentration of heavy metals in water with high selectivity and high sensitivity.

One aspect of the invention

A segment filling step in which a sample containing a metal ion to be detected, a chemiluminescent body, and an oxidizing agent reacting with the chemiluminescent body are sucked into a common channel and filled with a segment material therebetween;

Including the reaction detection step of performing a chemiluminescence reaction and detecting the luminescence intensity by injecting the segmented filler into a reactor connected to the common channel, wherein the segmented material is mixed between a chemiluminescent material, an oxidizing agent and a sample in the common channel. It relates to a chemiluminescence detection method to prevent.

In another aspect, the present invention

A reactor including a photodetector;

A storage unit for storing a sample containing a chemiluminescent body, an oxidizing agent reacting with the chemiluminescent body and a metal ion to be detected, respectively;

delete

A valve connected to the outlet side of each storage portion; And

It includes a pump that sucks the reagent or sample of each storage unit through the valve and fills it in a common channel, and then provides it to the reaction detector.

The common channel is formed between a valve and a pump, and is related to a chemiluminescence detection device in which fragment materials are filled between the chemiluminescent material, the oxidizing agent and the sample filled in the common channel so as not to be mixed with each other.

The chemiluminescence detection method and apparatus of the present invention separates samples containing metal ions, chemiluminescence and oxidizing agents into segmented materials and supplies them to the reactor, thereby preventing the chemiluminescence reaction from proceeding before reaching the reactor. Therefore, the present invention can minimize the decrease in sensitivity by reacting during the process in which the reagent and the sample are transferred to the reactor, so that it is possible to increase the analysis sensitivity compared to the conventional device.

In addition, the present invention induces the mixing of the sample with the chelating agent EDTA (ethylenediaminetetraacetic acid), which is a chelating agent, prior to being introduced into the reactor to selectively remove the interfering metal, so that the concentration of the chromium trivalent contributed to the chemiluminescence reaction can be more accurately measured.

In addition, the present invention does not require a mixing channel for mixing a sample and a reagent, and a device can be configured as a common channel between one pump and a valve.

1 is a conceptual diagram of a chemiluminescence detection device of the present invention.
2 is an embodiment of the present invention.
3 shows that the common channel is filled with a sample, a chemiluminescent material, an oxidizing agent, and a segmented material.
4 shows that the common channel is filled with a sample, a chemiluminescent body (luminol), an oxidizing agent (hydrogen peroxide), a chelating agent (EDTA), and air.
5 is another embodiment of the chemiluminescence detection device of the present invention.
6 is an embodiment of the segment filling step performed by FIG. 1.
7 is a table showing the order of performing the pre-treatment step, the amount of suction, and whether the suction / discharge.
8 shows the luminescence intensity of Comparative Example 1 and Example 1.
9 shows the light emission intensities of Examples 2 to 4.
FIG. 10 is a calibration curve in which the emission intensity measured while changing the chromium concentration in Example 1 is graphically displayed.
11 and 12 show the light emission intensities of Comparative Example 2, Comparative Example 3, Example 5, and Example 6.

Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings. In describing the embodiments of the present invention, when it is determined that detailed descriptions of related well-known functions or configurations may obscure the subject matter of the present invention, detailed descriptions thereof will be omitted. In addition, terms to be described later are terms defined in consideration of functions in the present invention, which may vary according to a user's or operator's intention or practice. Therefore, the definition should be made based on the contents throughout this specification.

1 is a conceptual diagram of the chemiluminescence detection device of the present invention, Figure 2 is an embodiment of the present invention, Figure 3 shows that the common channel is filled with a sample, chemiluminescent material, oxidizing agent and fragments, Figure 4 It shows that the common channel is filled with a sample, a chemiluminescent body (luminol), an oxidizing agent (hydrogen peroxide), a chelating agent (EDTA), and air, and FIG. 5 is another embodiment of the chemiluminescent detection device of the present invention.

The chemiluminescence detection method of the present invention includes a segment filling step and a reaction detection step. The metal detection method of the present invention may further include a pretreatment step prior to the segment filling step.

The segment filling step is a step in which a sample containing a metal ion to be detected, a chemiluminescent body and an oxidizing agent reacting with the chemiluminescent body are sucked into a common channel and filled with a segment material therebetween.

The metal (ion) to be detected may include all metals participating in the chemiluminescent reaction in which the chemiluminescent body (a reagent such as luminol) reacts with the oxidizing agent. For example, the metal (ion) to be detected may be chromium, copper, nickel, cobalt, iron, tin, magnesium, calcium, zinc, barium, strontium, vananium, lead, manganese, aluminum, silver, mercury or cadmium ions. have.

More specifically, the segment filling step is

delete

The sample, the chemiluminescent material and the oxidizing agent are each filled with a pump (sample, chemiluminescent material and any one of the oxidizing agent) from the storage unit to store the common channel and then suck the segmented material to suck the common channel Fill in. For example, as shown in FIG. 3, the sample is filled by inhaling a sample in a common channel and then inhaling air with a segment material.

Subsequently, in the segment filling step, any one of the remaining two fillings is sucked with a pump to fill the common channel, and then the segment material is sucked to fill the common channel. For example, if the oxidizer and air are sequentially sucked into the common channel with a pump, the sample-air-oxidant-air may be filled in the order (3 in FIG. 3).

Subsequently, in the segment filling step, the remaining filling material may be sucked with a pump to fill the common channel. For example, when a chemiluminescent body (eg, luminol) is sucked into a common channel with a pump, it may be filled in the order of sample-air-oxidant-air-chemiluminescent body-air (4 in FIG. 3).

That is, in the method of the present invention, the sample, the chemiluminescent body and the oxidizing agent are filled with a segment material between them so as not to be mixed with each other in the common channel.

The method of the present invention is not limited to the order of fillings in the common channel. However, the method of the present invention fills the segmented material between the fillings.

More specifically, the method of the present invention can be filled with a sample, a chemiluminescent material, an oxidizing agent and a segmental material in a common channel using a pump and a valve.

The method can be used without limitation 2-way valve, 3-way valve, multi-port valve, and the like. The present invention uses a multi-port valve in FIG. 1 and a 2-way valve in FIG. 5.

The method can be used without limitation as long as it is a kind capable of quantifying and inhaling the fluid. For example, the method may use a syringe pump, pulsation pump, piston pump and the like.

1 and 5, the common channel 1 is a pipe between the pumps 50 and 150 and the valves 40 and 140 (preferably a region indicated in red), and a sample entering the reactor , Chemiluminescent material, oxidizing agent and segmented material are filled.

The chemiluminescent material may be luminol, lucigenin or lophine.

The oxidizing agent may be hydrogen peroxide or oxygen.

The segmented material may be a solution (eg, oil) that does not mix with air, an inert gas, and an aqueous solution. For example, the inert gas may be nitrogen.

The luminol and hydrogen peroxide, which are chemiluminescent reagents, may be added to the buffer solution, respectively. For example, luminol and hydrogen peroxide may be added to a buffer solution of 0.25M carbonate, 0.1M KBr, and pH 10.9 at a predetermined concentration. For example, carbonate and borate may be used as the buffer solution. And KBr can be used as an additive to increase chemiluminescence.

As described above, the method of the present invention can prevent mixing between the sample, the chemiluminescent reagent and the chemiluminescent reagent in the common channel because the segment material is filled between the sample, the chemiluminescent body and the oxidizing agent.

Segment, which is a term used in the present invention, can be understood as a concept of not filling adjacent reagents, samples, oxidizing agents, etc., but filling and filling the segmented material between them (to prevent them from being mixed).

In the segment filling step, a chelating agent that forms a complex with an interfering metal ion in the sample may be inhaled and filled before or after the sample is inhaled. The chelating agent may be a compound that precipitates by forming a complex with a metal ion (iron, cobalt, copper, nickel, etc.) as an interfering substance in the sample. The interfering metal ion may be the rest of the metal ions participating in the chemiluminescence reaction except for chromium trivalent.

In the segment filling step, the chelating agent induces mixing of the sample in the common channel to selectively remove only interfering metal ions in the sample.

EDTA may be used as the chelating agent, but is not limited thereto. The chelating agent can be used by being added to the buffer solution.

Referring to FIG. 4, since the chelating agent and the interfering metal ion in the sample must react and form a complex before reaching the reactor, the chelating agent (EDTA) and the sample are filled adjacently.

The chemiluminescence detection method proposed by the present invention can be implemented in various ways. In the following specification, for convenience of description, chromium is used as an example of the metal (ion) to be detected, and the apparatuses of FIGS. 1 to 5 may be used. However, the metal detection method of the present invention may have a scope of rights to all heavy metals to which chemiluminescence methods other than chromium to which the technical idea of the present invention is applied and chemiluminescence detection devices other than FIGS. 1, 2 and 5 are applicable.

1, 2 and 5, the chemiluminescence detection device of the present invention is a pre-treatment reactor (10,110), reactor (20,120), storage unit (30, 130), valve 40 or a plurality of automatic valves (140) ) And pumps 50 and 150. In addition, the apparatus of the present invention includes a processor (60, 160) for controlling the pump and the valve to the automatic valve.

The reactors 20 and 120 undergo a chemiluminescence reaction therein and include a photodetector.

The storage units 30 and 130 respectively store a sample containing a chemiluminescent body, an oxidizing agent that reacts with the chemiluminescent body, and a metal ion to be detected.

The valves 40 and 140 are located between the outlet side of the reservoir and a single channel supply.

The pumps 50 and 150 inhale reagents or samples from each storage unit and fill them in the common channel 1 to provide them to the reactor.

The valve may be a multiport valve 40 or a 2-way automatic valve 140. The pump can be a syringe pump. Meanwhile, the apparatus of FIG. 5 includes a plurality of automatic valves 140 connected to the outlet side of each storage unit instead of the multi-port valve.

As previously mentioned, the method of the present invention may further include a pretreatment step depending on the metal to be detected. When the metal to be detected is chromium, the pre-treatment step is a step of dissolving metal ions fixed in the particulate matter by irradiating or heating the sample with ultraviolet rays, or by injecting an oxidizing agent and a reducing agent into the sample to oxidize or reduce the metal ions in the sample. It may be a step.

The pre-treatment step can use a known method without limitation. For example, the pre-treatment step may be carried out by adding an acid solution (eg, nitric acid, sulfuric acid, hydrochloric acid, etc.) and a reducing agent (eg, K ₂ SO ₃ ) to the sample.

Segment filling step, first, using a processor (60, can be displayed as a controller) to open the port 8 of the multi-port valve 40, the syringe pump 50 to drive the air (hereinafter, the segment material is air Is described as an example) and filled in the common channel 1 (1 in FIG. 4). Referring to Fig. 6, the volume of the inhaled air is presented, and the syringe pump can accurately inhale the amount into the common channel.

Next, the processor 60 opens port 1 of the multi-port valve 40, drives the syringe pump 50 to suck the pre-treated sample and fills it in the common channel 1 (2 in FIG. 4). As shown in Fig. 4, the common channel is sequentially filled with air and the sample by suction of the sample from the syringe pump.

Subsequently, as shown in FIG. 6, the processor opens port 7 of the multi-port valve 40 to drive the syringe pump to inhale EDTA, and then continues to air in port 8 and hydrogen peroxide in port 6 , Air in port 8 and luminol in port 5 can be inhaled sequentially. 3 of FIG. 4 shows the interior of the common channel in which suction has been completed with a syringe pump.

Segment filling of the present invention can be achieved only by filling air, which is a segment material, between a sample, an oxidizing agent (hydrogen peroxide), and a chemiluminescent body (luminol). It is not limited.

That is, as mentioned above, the method of the present invention can be filled by changing the order of the sample and the chelating agent (EDTA). In addition, the positions of the chemiluminescent body (luminol) and the oxidizing agent (hydrogen peroxide) in 3 of FIG. 4 may be interchanged. In addition, the present invention can be filled with a chemiluminescent material (luminol) or an oxidizing agent (hydrogen peroxide) in the front end of the sample, and the air between the sample.

The reaction detection step is a step of performing a chemiluminescent reaction and detecting the luminescence intensity by injecting the segmented filler into a reactor connected to the common channel.

The reaction detection step may use a reactor 20 having a photodetector. The photodetector may process the light emission intensity generated in the reactor and provide it to the processors 60 and 160 or the display units 70 and 170.

The reaction detection step may provide a pH suitable for a chemiluminescence reaction.

In the case of a luminol chemiluminescence reaction, basic conditions of pH 10 or higher may be provided.

The device of the present invention may further include a loop 80 by extending a length of the tube by winding a part of the common channel 1. The common channel may be in the form of a flexible tube.

1 and 2, the multi-port valve 40 has a common channel 1 connected to a central hole (port), and a plurality of holes (ports) formed on the side and the storage unit 30, reagents, samples, etc. Connected tubes (pipes) are installed.

The present invention uses the valve 40, the syringe pump 50, the common channel (1).

The processor 60 of the present invention can control the devices according to the input value.

The present invention may perform the pre-treatment step in the same manner as the segment filling step using the apparatus of FIG. 1. 7 is a table showing the order of performing the pre-treatment step, and the amount of suction and suction / discharge.

The apparatus of the present invention is efficient because it can perform not only the segment filling and the reaction detection step, but also a metal pretreatment reaction such as chromium.

The apparatus of FIG. 5 uses controllable automatic valves 140, 140 'instead of the multi-port valve of FIG. Even using the apparatus of FIG. 5, air, reagents, and chemiluminescent reagents can be filled in the common channel 1 as shown in FIG. For example, only the automatic valve located at the front end of the air is opened, and the remaining automatic valves are kept closed to inhale air through a syringe pump. After repeating this process several times, as shown in FIG. 4, after filling the air-sample-EDTA-air-hydrogen peroxide-air-luminol with suction, the automatic valve in front of the reaction detector can be opened and injected into the reaction detector.

 Hereinafter, the present invention will be described in detail with reference to the accompanying examples and drawings. However, the attached examples illustrate only specific embodiments of the present invention, and are not intended to limit the scope of the present invention.

Example 1

Pretreatment was performed in the order and content described in FIG. 7, and samples, reagents, and air were filled in the common channel of FIG. 1 in the order and content shown in FIG. 6 (filled as 3 in FIG. 3). After opening the port 2 and sending the filled contents to the reaction detector, the intensity of luminescence was examined. Table 1 shows the content of reagents used.

Reagent name density volume Standard sample Cr (NO ₃ ) ₃ · 9H ₂ O 0.005 ~ 1ppm 0.3 mL Chemiluminescent reagent Luminol 1mM 1 mL Hydrogen peroxide 0.1M 1 mL Chelating agent EDTA 10mM 0.3 mL

Chemiluminescent reagent: 0.25M carbonate, 0.1M KBr, pH 10.9 prepared in buffer EDTA: prepared in distilled water

Examples 2 to 4

The luminescence intensity was investigated in the same manner as in Example 1, except that the sample and the chelating agent were changed as shown in Table 2 below.

sample Chelating agent Example 2 1ppm chromium trivalent Replaced with distilled water Example 3 1ppm chromium trivalent + 10ppm iron divalent Replaced with distilled water Example 4 1ppm chromium trivalent + 10ppm iron divalent EDTA

Comparative Example 1 Pre-treatment was performed in the order and content described in FIG. 7, and the pre-treated sample, EDTA, hydrogen peroxide, and luminol were filled in a common channel without segmentation, and then injected into a reactor to measure the luminescence intensity.

Example 5, Comparative Example 2

It was carried out in the same manner as in Example 1 and Comparative Example 1, except that a solution containing 10 ppm iron divalent ion was used as a sample. However, the chelating agent was replaced with distilled water.

Example 6, Comparative Example 3

It was carried out in the same manner as in Example 1 and Comparative Example 1, except that a solution containing 10 ppm cobalt divalent ion was used as a sample. However, the chelating agent was replaced with distilled water.

8 shows the luminescence intensity of Comparative Example 1 and Example 1. Referring to FIG. 8, it can be confirmed that the light emission intensity of Example 1 was significantly increased compared to Comparative Example 1.

Figure 9 shows the light emission intensity of Examples 2 to 4. Referring to FIG. 9, Example 4 shows a light emission intensity lower than that of Example 3, while the light emission intensity of Example 4 is almost the same. That is, it can be confirmed that the EDTA used in Example 4 did not participate in the chemiluminescence reaction by forming a complex with iron before reaching the reactor.

FIG. 10 is a calibration curve showing a graph of luminescence intensity measured while changing the chromium concentration in Example 1. Referring to FIG. 10, since the luminescence intensity according to the chromium concentration increases linearly, the method or apparatus of the present invention It can be used as a chrome sensor.

11 and 12 show the light emission intensities of Comparative Example 2, Comparative Example 3, and Example 5 and Example 6. 11 and 12, Example 5 (compared to Comparative Example 2 (light emission intensity value 0.839V), Comparative Example 3 (light emission intensity value 0.37V) not segmentally filled even when iron and cobalt-containing samples were used instead of chromium) The light emission intensity value 0.951V) and Example 6 (light emission intensity value 0.437V) show high emission intensity. That is, the present invention can more accurately measure most metals participating in the chemiluminescence reaction.

Those skilled in the art to which the present invention pertains will understand that the present invention can be implemented in a modified form without departing from the essential characteristics of the present invention. Therefore, the disclosed embodiments should be considered in terms of explanation, not limitation. Therefore, the scope of the present invention is not limited to the above-described embodiment, it should be interpreted to include the contents described in the claims and various embodiments within the scope equivalent thereto.

Claims (3)

A storage unit for storing a sample containing a chemiluminescent body, an oxidizing agent reacting with the chemiluminescent body and a metal ion to be detected, and a common channel connected to a central hole (port) and forming a pipe and a channel connected to the storage unit Metal using a chemiluminescent device including a multi-port valve having a plurality of holes (ports), a pump that inhales reagents or samples from each reservoir through the multi-port valve, fills the common channel, and provides it to the reactor. In the detection method,
A segment filling step of inhaling the sample, chemiluminescent material and oxidizing agent into the common channel and filling them with a segment material; And
Including the reaction detection step of performing a chemiluminescence reaction and detecting the luminescence intensity by injecting the segmented filling into a reactor connected to the common channel,
The segment filling step
A first filling step of inhaling the filling of any one of the sample, chemiluminescent material and oxidizing agent with the pump to fill the common channel, and then inhaling the segmented material to fill the common channel.
A second filling step of inhaling any one of the remaining two fillings not filled in the first filling step with the pump to fill the common channel and then inhaling the segmented material to fill the common channel;
And a third filling step of filling the common channel by suctioning the remaining filling material that is not filled in the second filling step with the pump,
The metal ion to be detected is an iron or cobalt ion,
The common channel is formed between the multi-port valve and the pump,
The segmented material is air,
The segmented material is a metal detection method using chemiluminescence, characterized in that to prevent mixing between the chemiluminescent material, the oxidizing agent and the sample in the common channel. delete The method according to claim 1, wherein the chemiluminescent material is luminol, lucigenin or lophine.

Images