JP3623777B2 - Quantitative determination method of environmental pollutants and quantitative kit used therefor - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a novel method for quantitative determination of environmental pollutants and a determination kit used therefor.
[0002]
[Prior art]
In recent years, from the viewpoint of prevention of environmental pollution, there is an increasing need to quantify trace components in the air, water, or soil, so these trace components can be quantified easily and accurately. There is an increasing demand for methods.
One method for analyzing such a trace component is a colorimetric determination method for heavy metal ions. This is a method of reacting an analyte with a coloring reagent and pre-concentrating the resulting reaction product, followed by spectroscopic analysis. It can be quantified in the microgram order and is used in a wide range of fields. Yes.
[0003]
However, in this method, preconcentration is an indispensable step for increasing analytical sensitivity, and it is performed using means such as evaporation concentration, solvent extraction, aggregation, dialysis, etc., but the operation is complicated. There are problems such as requiring a long time, costly, unstable sample, and use of an organic solvent that may cause carcinogenicity, and the range of use is inevitable.
[0004]
In order to deal with such problems, a coloring reagent having a large molecular extinction coefficient that specifically reacts with the analyte [“Fine Chemical”, Vol. 20, No. 6, pages 5 to 12 (1991)], A method for concentrating a reaction product of an analyte and a coloring reagent on a membrane filter [“Analyst”, Vol. 112, pages 1257 to 1260 (1987)] has been proposed, but it is still practical. It is not always satisfactory for use.
[0005]
On the other hand, in the field of environmental analysis, a sample is collected particularly at the site, and the sample is taken back to a place equipped with an analytical instrument for analysis. Although this method has the advantage of high analysis accuracy, it takes a long time to obtain analysis results and has the disadvantage of increasing costs. Is desired.
[0006]
By the way, this on-site analysis does not require any special equipment or instruments for sample separation and detection, and can be obtained quickly and with high sensitivity by simple operation, and at a sufficiently low cost. It is required to be able to obtain.
[0007]
[Problems to be solved by the invention]
An object of the present invention is to provide a method for easily and accurately quantifying an extremely small amount of components causing environmental pollution, particularly heavy metal ions, and a quantification kit used therefor.
[0008]
[Means for Solving the Problems]
As a result of intensive research to develop a method capable of easily and quantitatively analyzing trace amounts of pollutants, the present inventors have found that a thermoreversible thermosensitive polymer compound that is hydrophilic at low temperatures and hydrophobic at high temperatures. By utilizing the characteristics, it was found that trace contaminants can be quantified easily and accurately, and the present invention has been made based on this finding.
[0009]
That is, the present invention is (a) mixing an environmentally collected sample containing a trace amount of contaminants with water, stirring well, and allowing to stand, separating the supernatant, and mixing with the pretreatment liquid;
(B) Maintain the above mixture at an arbitrary temperature and dissolve it by adding a thermo-reversible thermosensitive polymer of a fine fibrous solid that is hydrophilic at low temperatures and hydrophobic at high temperatures, which has a transition temperature higher than that temperature. The process of
(C) raising the temperature of the solution above the transition temperature of the thermosensitive polymer compound to form a solid, and then separating the liquid part from the solid;
(D) a thermoreversible thermosensitive polymer compound that is hydrophilic at a low temperature and hydrophobic at a high temperature in a solid state, in which this liquid portion is encapsulated with a hydrophobic coloring reagent that reacts with the above-mentioned trace contaminants to develop a color; Mixing at a temperature below its transition temperature to form a solution;
(E) The temperature of the solution is raised above the transition temperature, and the solid part composed of the thermosensitive polymer compound deposited by inclusion of the colored compound produced by the reaction between the trace contaminant and the coloring reagent is removed from the liquid part. Separating,
(F) a step of dissolving the solid part obtained in (e) in water or a solvent at a temperature lower than the transition temperature of the thermosensitive polymer compound to form a solution, and (g) measuring the absorbance of the obtained solution. Or a method for quantitative determination of environmental pollutants, characterized in that it comprises a step of determining the content of trace pollutants by colorimetric determination with a standard product, and suitable for use in this method,
(A) A test tube containing a necessary amount of pretreatment liquid and a marked line for adding a sample;
(B) a test tube containing a thermoreversible thermosensitive polymer compound that is hydrophilic at a required low temperature and hydrophobic at a high temperature;
(C) A test tube that receives the liquid portion separated from the hydrophilic-hydrophobic thermoreversible polymer compound solid matter attached to the tube wall after the treatment (B),
(D) contains a necessary amount of a thermoreversible polymer compound that is hydrophilic at low temperatures and hydrophobic at high temperatures, which is encapsulated with a hydrophobic coloring reagent that reacts with a trace amount of contaminants to be quantified; and (C) A test tube with a marked line for adding the liquid portion in it,
(E) a small container containing a solvent for dissolving the solid matter adhered to the tube wall of (D) after the above treatment, and (F) a colorimetric band corresponding to the concentration of the trace contaminant determined by the standard reagent. The present invention provides a kit for quantitative determination of environmental pollutants by combining a colorimeter printed with the above.
[0010]
DETAILED DESCRIPTION OF THE INVENTION
The thermoreversible thermosensitive polymer compound that is hydrophilic at a low temperature and hydrophobic at a high temperature used in the present invention is a polymer hydrate (oxonium hydroxide) that is formed at a predetermined temperature, that is, at a low temperature below the transition temperature. The polymer has the property that the polymers are aggregated and precipitated by dehydration at a temperature higher than the above temperature, and is hydrophilic at the transition temperature or lower and dissolves in water, but at a temperature higher than the transition temperature. Shows hydrophobicity and precipitates.
[0011]
In the present invention, a hydrophilic-hydrophobic thermoreversible thermosensitive polymer compound having a transition temperature of 0 to 90 ° C., preferably 10 to 60 ° C. is used. Then, the thing with the transition temperature which shows hydrophobicity is preferable. This transition temperature can be changed depending on the type of monomer composing the polymer compound and the content ratio of the comonomer, but it can also be changed by adjusting the salt concentration and pH of the aqueous solution. it can.
[0012]
The thermoreversible thermosensitive polymer compound itself, which is hydrophilic at low temperatures and hydrophobic at high temperatures, is a known substance. Examples thereof include N-ethylacrylamide, Nn-propylacrylamide, N-isopropylacrylamide, At least one selected from N-cyclopropylacrylamide, N, N-ethylmethylacrylamide, N, N-diethylacrylamide, N-acryloylpyrrolidine, N-acryloylpiperidine, N-acryloylmorpholine and the corresponding methacrylamide derivatives Polymers or copolymers of these monomers, or these monomers and hydrophilic monomers such as N-vinyl pyrrolidone, vinyl pyridine, acrylamide, methacrylamide, N-methyl acrylamide, hydroxyethyl methacrylate, hydroxy Cyl acrylate, hydroxymethyl acrylate, unsaturated carboxylic acids such as acrylic acid and methacrylic acid and their salts, unsaturated sulfonic acids such as vinyl sulfonic acid and styrene sulfonic acid, N, N-dimethylaminoethyl methacrylate, N, N-diethylaminoethyl methacrylate, N, N-dimethylaminopropyl acrylamide, etc., or hydrophobic monomers such as acrylic or methacrylic esters such as ethyl acrylate, methyl methacrylate, glycidyl methacrylate, or Nn-butyl acrylamide N-alkyl substituted acrylamide or methacrylamide such as Nn-butyl methacrylate, at least one selected from vinyl chloride, acrylonitrile, styrene, vinyl acetate, etc. And a copolymer of mer thereof.
[0013]
In general, copolymerization with a hydrophilic monomer raises the transition temperature compared to a homopolymer, and copolymerization with a hydrophobic monomer lowers the transition temperature than a homopolymer. Thus, a hydrophilic-hydrophobic thermoreversible thermosensitive polymer compound having a desired transition temperature can be formed.
[0014]
By the way, generally, trace substances that cause environmental pollution are usually contained in a huge matrix such as soil and wastewater. To quantitatively analyze this, first separate the trace substance to be analyzed from the huge matrix. There is a need to. Until now, this separation has been carried out by inducing trace substances into hydrophobic substances such as chelate compounds and then extracting them from large matrices using hydrophobic organic solvents such as chloroform and ether. The method requires a large amount of organic solvent and is not always satisfactory in terms of extraction efficiency.
[0015]
However, an aqueous solution containing the thermoreversible thermosensitive polymer compound at a concentration of 0.01 to 0.5% by mass has a polarity close to that of a lower alcohol, and becomes a hydrophobic solvent at a certain concentration or higher. In addition, it has the property of being dehydrated by temperature stimulation to form a solid phase that can be separated from the aqueous phase. When the hydrophobic matrix coexists, it is taken into the solid phase of the thermoreversible thermosensitive polymer compound and removed from the aqueous phase. At this time, the partition coefficient between the aqueous phase and the solid phase is the hydrophobicity of the matrix substance. The higher the nature, the larger.
[0016]
Therefore, keeping trace amounts of substances to be quantified hydrophilic, adding the above thermoreversible thermosensitive polymer compound at a temperature below its transition temperature, and then heating it above its transition temperature, the matrix material is collected. And can be separated. This separation method does not require any equipment, and can be performed simply and in a short time by simply separating the supernatant to be quantified by tilting. Is preferred.
[0017]
In the method of the present invention, by utilizing the property of the thermoreversible thermosensitive polymer compound that is hydrophilic at such a low temperature and hydrophobic at a high temperature, a trace contaminant to be quantified is separated from a sample collected from the environment. To do. The trace pollutant may be an inorganic substance such as heavy metal ions or an organic substance such as formaldehyde.
[0018]
That is, first, a predetermined amount of a sample is collected from the environment, mixed with water to transfer trace substances in the sample to water, and collected as a supernatant. A sample solution is prepared according to the preparation method shown in “Environmental Standards Concerning Soil Contamination” (August 23, 1991, Environment Agency Notification No. 46) [Step (A)].
[0019]
Next, a predetermined amount of the sample solution is maintained at a temperature lower than the transition temperature of the thermoreversible thermosensitive polymer compound that is hydrophilic at low temperatures and hydrophobic at high temperatures. Add thermosensitive polymer compound, mix well and dissolve [(b) step]. In this process, the mixture forms a single aqueous phase.
[0020]
Next, the temperature of the mixture is raised above the transition temperature of the thermoreversible thermosensitive polymer compound. If a solid substance is produced at this stage and a matrix substance is present, it is taken into the solid phase. Therefore, if only the liquid part is separated from the solid substance by tilting or the like, a test solution from which the matrix substance has been removed is obtained. Obtained [(C) step].
[0021]
Next, the trace substance detection material prepared in advance in this test solution is at a temperature lower than the transition temperature of the thermoreversible thermosensitive polymer compound that is hydrophilic at low temperatures and hydrophobic at high temperatures. Add and dissolve [(D) step].
[0022]
This trace substance detection material is prepared by including a hydrophobic chelate-forming coloring reagent in a thermoreversible thermosensitive polymer compound that is hydrophilic at low temperatures and hydrophobic at high temperatures. As the hydrophobic chelate-forming color-developing reagent to be included, it can be arbitrarily selected from those used so far as a color-developing reagent that forms a chelate compound with a predetermined trace amount of contaminant in photoanalysis.
[0023]
Examples of such a coloring reagent include dithizone that forms a red complex with cadmium Cd (II) for detection of heavy metal ions, 2-nitroso-1-naphthol that forms a red complex with cobalt Co (II), and chromium Cr ( VI) diphenylcarbazide that forms a reddish purple complex with mercury, thiothenoyltrifluoroacetone that forms a yellow complex with mercury Hg (I) and Hg (II), and didizone that forms a red complex with lead Pb (II) .
[0024]
In addition, as a coloring reagent for organic environmental pollutants such as formaldehyde, a combination of dye fuchsin decolorized with sulfurous acid, N-benzenesulfonylhydroxylamine and iron chloride, 4-amino-3-hydrazino-5-mercapto-1, There are 2,4-triazole, chromotropic acid and the like.
[0025]
The trace contaminant detection material used in the method of the present invention is prepared by dissolving the hydrophobic chelate-forming color-developing reagent in a water-miscible organic solvent such as acetone, dimethylformamide, dimethyl sulfoxide and the like. It can be produced by mixing an aqueous solution of a hydrophilic-hydrophobic thermoreversible thermosensitive polymer compound at a temperature not higher than its transition temperature and freeze-drying the mixture.
[0026]
In this case, the concentration of the coloring reagent in the organic solvent is 0.5 to 1.0% by mass, and the concentration of the thermosensitive polymer compound in the aqueous solution is 0.2 to 15% by mass. The range of is used.
Freeze-drying can be performed, for example, at a temperature of −20 ° C. to −50 ° C. under reduced pressure of 0.5 to 100 Pa.
In this way, a cotton-like material for detecting trace contaminants in which the coloring reagent is uniformly included in the thermosensitive polymer compound is obtained.
[0027]
Until now, the organic coloring reagent has been used as a solution dissolved in an organic solvent, but the stability of the solution is low, and it often deteriorates in a short time. However, since the above-described trace contaminant detection material is solid, it is stable and can sufficiently cope with field analysis under severe measurement conditions. In addition, by coexisting with the polymer compound, a chelate-forming color-developing reagent that is usually poorly soluble in water can be easily mixed with water and the color reaction can proceed rapidly.
[0028]
In the method of the present invention, the test solution to which the trace contaminant detection material is added is heated to a temperature higher than the transition temperature of the thermosensitive polymer compound. As a result of this treatment, the hydrophobic colored compound produced by the reaction between the trace contaminants and the coloring reagent is deposited in a solid state while being encapsulated in the thermosensitive polymer compound, and adheres to the vessel wall, so that the solid part is adhered as it is. Leave only the liquid part by tilting [step (e)].
[0029]
Next, it dissolves using a predetermined amount of water or a solvent having a temperature lower than the transition temperature of the thermosensitive polymer compound using the solid portion adhered to the vessel wall to obtain a colored solution [(f) step].
[0030]
Then, the absorbance of the colored solution thus obtained is measured with a photometer or colorimetrically determined with a standard product to determine the amount of trace contaminants contained therein [(g) ].
In this way, trace contaminants can be quantified easily and quickly on-site from a sample collected from the surrounding environment.
[0031]
The quantification of the above step (g) is advantageously carried out by colorimetry with a standard color table prepared in advance based on a standard of known concentration, but at the light absorption wavelength of the colored solution of the environmental pollutant produced. Absorbance can also be performed against that of a standard of known concentration.
[0032]
The operation at low temperature in the method of the present invention is preferably carried out in the range of 5 to 10 ° C., and the operation at high temperature is preferably carried out in the range of 20 to 45 ° C. Therefore, the thermosensitive polymer compound having a transition temperature between these ranges It is advantageous to select and use.
[0033]
The method of the present invention is preferably carried out using a quantitative kit in which tools are combined so that the operations in each step can be performed smoothly.
FIG. 1 is a perspective view showing an example of such a quantitative kit.
A method for quantifying hexavalent chromium using a quantification kit will be described with reference to this figure. This kit includes a case 1, three round bottom test tubes 2, 4, 5 and one flat bottom test tube 6, a small bottle 7 containing a solvent, a dropper 8 and a colorimeter 9 (a colorimetric band 10 as an accessory). Is included). Then, the sample to be quantified is first stored in advance with a pretreatment liquid, for example, a perchloric acid mixed solution 3, and injected into the test tube 2 with a marked line indicating the required amount of the sample to the position of the marked line, Mix well with the pretreatment solution.
[0034]
Next, the test tube 4 containing the thermoreversible thermosensitive polymer compound that is hydrophilic at low temperatures and hydrophobic at high temperatures is kept at a temperature lower than the transition temperature of the thermoreversible thermosensitive polymer compound, and into the tube. A sample is injected from the test tube 2.
Next, the test tube 4 is heated to a temperature equal to or higher than the transition temperature of the thermoreversible polymer compound, vigorously shaken to adhere the deposited solid to the tube wall, and only the liquid part is transferred to the test tube 5 by tilting.
[0035]
Next, a thermoreversible polymer compound that is hydrophilic at low temperatures and hydrophobic at high temperatures encapsulating a hydrophobic coloring reagent such as diphenylcarbazide is housed, and a flat bottom test tube 6 is marked with a marked line at a required position. The liquid in the test tube 5 is cooled to the position of the marked line at low temperature, and the contents are dissolved, then heated above the transition temperature of the thermoreversible polymer compound and shaken vigorously. After adhering to the tube wall, the liquid part is discarded by tilting, leaving only the solid part. Next, a small amount of solvent is poured from the small bottle 7 into the test tube 6 with the dropper 8, and the solid mass is completely dissolved to obtain a colored liquid.
[0036]
The flat-bottomed test tube 6 containing the colored liquid thus prepared is inserted into a predetermined hole of the colorimeter, and compared with the color of the colorimetric band through the observation hole, the place where the two match each other is determined. By reading the numerical value, the chromium content can be determined.
Of the test tubes, the test tube 6 to be inserted into the colorimeter has a flat bottom when compared with the color of the colorimetric band, but the other test tubes do not need to have a flat bottom.
[0037]
【The invention's effect】
According to the method of the present invention, particularly by using a predetermined quantification kit, it is possible to quickly quantify environmental pollutants on site with a simple operation.
[0038]
【Example】
EXAMPLES Next, although an Example demonstrates this invention further in detail, this invention is not limited at all by these examples.
[0039]
Reference example 1
4 g of poly (N-isopropylacrylamide) (hereinafter abbreviated as PNIPAAm) having a transition temperature of about 30 ° C. and a mass average molecular weight of about 50000 is added to a solution of 0.02 g of diphenylcarpazide dissolved in 5 ml of acetone, and dissolved. Was added to dilute until the total volume reached 100 ml. Next, this solution was freeze-dried at a temperature of −40 ° C. and a pressure of 10 Pa for 24 hours to obtain PNIPAAm (hereinafter abbreviated as DPC-PNIPAAm) enclosing cotton-like diphenylcarbazide.
[0040]
Reference example 2
Add 0.2 g of the same PNIPAAm used in Example 1 to a solution of 0.001 g of dithizone dissolved in 5 ml of acetone (or ethyl alcohol) and add 5 ° C. water until the total amount becomes 100 ml. Diluted. Then, this solution was freeze-dried under the same conditions as in Reference Example 1 to obtain PNIPAAm (hereinafter abbreviated as DTZ-PNIPAAm) in which dithizone was included.
[0041]
Example 1
0.971 g of potassium chromate was weighed and dissolved by adding water to a total volume of 50 ml to prepare a 0.1 M concentration chromate standard stock solution. Next, this chromic acid standard stock solution was diluted with water to prepare 10 ml each of a chrome standard solution having a chromium content of 5.2 to 156 ppb.
10 ml of each of these chromium standard solutions was placed in a test tube with a lid, and 3 ml of a perchloric acid mixed solution (8 M sodium perchlorate + 0.0025 M perchloric acid) was added and mixed, and then obtained in Reference Example 1 at 5 ° C. DPC-PNIPAAm was added and shaken to dissolve. Furthermore, after maintaining the temperature for 5 minutes to complete the Cr-DPC complex formation reaction, the mixture was heated to 45 ° C. for 1 minute and immediately shaken vigorously for 10 seconds to allow the produced solid to adhere to the test tube wall. It was.
Next, the liquid part was removed by decantation, and 0.5 ml of acetone was added to dissolve the solid part to obtain a red solution.
The result of measuring the absorbance of this solution at a wavelength of 540 nm is shown in FIG. The black circles in the figure are the results when the heavy metal detection material of the present invention is used, and the white circles are the results when the standard solution is measured by a conventional method.
[0042]
As can be seen from this figure, the Cr (VI) concentration and absorbance show a good proportional relationship (correlation coefficient 0.999), and Cr (VI) of 5 ppb or more in the sample increases this by 20 times or more. It can measure with high efficiency by concentrating. Since a sample with Cr (VI) of 10 ppb or more can be visually measured, if a colorimetric band of a standard solution row of a calibration curve is prepared in advance, a highly toxic Cr ( IV) Cr (VI) can be quantified without using a standard solution.
[0043]
Example 2
The standard solution for atomic absorption (1000 mg / l) was appropriately diluted with water to prepare a standard solution having a cadmium content of 0 to 0.4 mg / l.
10 ml of each of these cadmium standard solutions was placed in a test tube with a lid, and DTZ-PNIPAAm obtained in Reference Example 2 was added at 5 ° C. and shaken to dissolve. Further, 0.1 ml of 10% NaOH aqueous solution was added and heated to 45 ° C. for 10 seconds and immediately shaken vigorously for 10 seconds to take in the produced Cd-DTZ complex and deposit the precipitated PNIPAAm solid on the test tube wall.
Next, the liquid part was removed by decantation, and 1 ml of acetone was added to dissolve the solid part to obtain a red solution. The results of measuring the absorbance at a wavelength of 535 nm for this solution are shown in FIG.
[0044]
As can be seen from this figure, the Cd (II) concentration and absorbance are in a good proportional relationship, and 0.005 mg / l or more of Cd (II) in the sample solution should be concentrated 20 times or more. Can be measured with high efficiency. Further, visual measurement is possible with a sample of 0.01 mg / l or more. Therefore, if a colorimetric table for the standard solution row is prepared in advance, Cd (II) can be quantified without using a highly toxic Cd (II) standard solution during measurement in the field.
[Brief description of the drawings]
FIG. 1 is a perspective view of a kit of the present invention.
FIG. 2 is a graph showing the relationship between Cr (VI) concentration and absorbance at a wavelength of 540 nm.
FIG. 3 is a graph showing the relationship between Cd (II) concentration and absorbance at a wavelength of 535 nm.
[Explanation of symbols]
1 Case 2, 4, 5, 6 Test tube 3 Pretreatment liquid 7 Small bottle 8 Dropper 9 Colorimeter 10 Colorimetric band

Claims (7)

(B) A step of mixing an environmentally-collected sample containing trace contaminants with water, stirring it well, leaving it, separating the supernatant, and mixing it with the pretreatment solution;
(B) Maintain the above mixture at an arbitrary temperature and dissolve it by adding a fine fibrous solid thermoreversible thermosensitive polymer compound that is hydrophilic at low temperatures and hydrophobic at high temperatures with a transition temperature higher than that temperature. The process of
(C) raising the temperature of the solution above the transition temperature of the thermosensitive polymer compound to form a solid, and then separating the liquid part from the solid;
(D) a thermoreversible thermosensitive polymer compound that is hydrophilic at a low temperature and hydrophobic at a high temperature in a solid state that includes a hydrophobic coloring reagent that reacts with the above-mentioned trace contaminants and colors the liquid part; Mixing at a temperature below its transition temperature to form a solution;
(E) The temperature of the solution is raised to the transition temperature or higher, and the solid portion composed of the thermosensitive polymer compound deposited by inclusion of the colored compound produced by the reaction between the trace contaminant and the coloring reagent is removed from the liquid portion. Separating,
(F) A step of dissolving the solid part obtained in (e) in water or a solvent at a temperature lower than the transition temperature of the thermosensitive polymer compound to make a solution, and (g) measuring the absorbance of the obtained solution. Or a method for quantitative determination of environmental pollutants, characterized by comprising a step of colorimetrically determining the content of trace contaminants with a standard product. The method for quantifying environmental pollutant trace substances according to claim 1, wherein the trace pollutant in the step is heavy metal. The method for quantifying environmental pollutant trace substances according to claim 1, wherein the trace pollutant in the step (a) is a harmful inorganic or organic substance. 3. The environmental pollutant trace substance according to claim 2, wherein the hydrophobic coloring reagent that develops color by reacting with a trace pollutant in the step is a hydrophobic chelate-forming reagent that forms a chelate compound with a heavy metal ion. Quantification method. (A) A test tube containing a necessary amount of pretreatment liquid and a marked line for adding a sample;
(B) a test tube containing a thermoreversible thermosensitive polymer compound that is hydrophilic at a required low temperature and hydrophobic at a high temperature;
(C) A test tube that receives the liquid portion separated from the hydrophilic-hydrophobic thermoreversible polymer compound solid matter attached to the tube wall after the treatment (B),
(D) contains a necessary amount of a thermoreversible polymer compound that is hydrophilic at low temperatures and hydrophobic at high temperatures, which is encapsulated with a hydrophobic coloring reagent that reacts with a trace amount of contaminants to be quantified; and (C) A test tube with a marked line for adding the liquid portion in it,
(E) A small container containing a solvent for dissolving the solid matter adhered to the tube wall of (D) after the above treatment, and (F) a colorimetric band corresponding to the concentration of the trace contaminant determined by the standard reagent. Kit for quantitative determination of environmental pollutants by combining a colorimeter printed with The thermoreversible thermosensitive polymer that becomes hydrophilic at low temperatures and hydrophobic at high temperatures in (B) is poly (N-isopropylacrylamide), and the trace contaminant to be quantified in (D) is chromium, which reacts with it. The thermoreversible polymer compound that is hydrophilic at low temperatures and hydrophobic at high temperatures, which is encapsulated with the hydrophobic coloring reagent that is colored in this way, is poly (N-isopropylacrylamide) that includes diphenylcarbazide, ( The determination kit according to claim 5, wherein the solvent of E) is acetone. The thermoreversible thermosensitive polymer compound that is hydrophilic at low temperature and hydrophobic at high temperature is poly (N-isopropylacrylamide), and (D) the trace environmental pollutant to be quantified reacts with cadmium. A thermoreversible polymer compound that is hydrophilic at low temperatures and hydrophobic at high temperatures that includes a hydrophobic coloring reagent that is colored in color is poly (N-isopropylacrylamide) that includes dithizone, and (E) 6. The determination kit according to claim 5, wherein the solvent is acetone.

Images