KR20090120123A - Chemical sensor array useful for the detection of volatile orgarnic compound in ultra-low concentration - Google Patents

Abstract

PURPOSE: A chemical sensor array is provided to accurately detect volatile organic compounds even in ultra-low concentration because the array can be coordinated with metal ions and to be stable by avoiding the influence of moisture in air. CONSTITUTION: A chemical sensor array for detecting volatile organic compounds comprises at least one chemoresponsive dye and a porous polymer supporter for supporting the same. The volatile organic compound is selected from the group consisting of amines, aldehydes, acids, ethers, esters, alcohols, arenes, and halocarbons. The chemoresponsive dye comprises a compound of chemical formula 1, wherein M is selected from the group consisting of Co, Cu, Fe, Mn, Ni, Cr and Zn; and R is phenyl or p-methoxyphenyl.

Description

High Sensitivity Chemical Sensor Arrays Useful for Detection of Volatile Organic Compounds {CHEMICAL SENSOR ARRAY USEFUL FOR THE DETECTION OF VOLATILE ORGARNIC COMPOUND IN ULTRA-LOW CONCENTRATION}

The present invention can easily and easily identify a volatile organic compound, and relates to a high sensitivity chemical sensor array having high stability and reliability because it is not affected by moisture.

In a modern industrial society where a variety of pollutants are increasing, air or water quality management is essential for a pleasant environment. Trace amounts of volatile organic compounds (VOCs) dissolved in air or in water are a threat to human health, and a measuring device capable of detecting the concentration of VOCs contained in them and determining the concentration thereof is required.

Sensors capable of detecting gaseous compounds have a very wide range of applications and thus are economically and industrially important.

However, conventional sensors can detect only normal VOCs with low sensitivity and no strong binding force such as ligand binding, and thus have a bad smell and a functional group capable of strongly coordinating with metal ions. Inappropriate.

In addition, the existing sensor is very sensitive to moisture in the air, causing problems such as stability, there is a problem that must use expensive signal transduction equipment.

It is an object of the present invention to provide a chemical sensor array capable of coordinating with metal ions and accurately detecting low concentrations of VOCs that are harmful to the human body and exhibit an adverse smell.

Another object of the present invention is to provide a stable and reliable chemical sensor array is not affected by moisture in the air.

It is still another object of the present invention to provide a chemical sensor array that is portable and inexpensive to manufacture.

In order to achieve the above object,

According to one aspect of the invention,

A chemical sensor array for detecting volatile organic compounds (VOCs), consisting of one or more chemoresponsive dyes and a polymeric porous support supporting the same, can be presented.

In addition, according to another aspect of the present invention, it is possible to provide a method for detecting a volatile organic compound (VOC) using the chemical sensor array described above.

Hereinafter, the present invention will be described in detail.

The chemical sensor array for detecting VOCs of the present invention includes one or more chemoresponsive dyes and a polymeric porous support that supports them.

The chemically sensitive dye reacts with the VOC to cause a color change so that the type and concentration of the VOC contained in the sample can be easily identified. In other words, unlike other sensors, chemically sensitive dyes are used as detectors, so the VOCs react with the detectors in the sensor, causing color changes.

The VOCs include, but are not limited to, amines, aldehydes, ketones, acids, ethers, esters, alcohols, arenes and halocarbons. Specifically, dichloromethane, 1-hexanethiol, acetone, ethyl acetate, acetic acid, propionic acid, triethyl phosphite, tributyl phosphite, chloroform, n-butylamine, DMF, pyridine, hexylamine, dipropylamine, ethanol , 1-butanol, THF, DMSO, and the like.

The chemically sensitive dye includes a compound having the following formula.

<Formula>

Wherein M is selected from the group consisting of CO, Cu, Fe, Mn, Ni, Cr and Zn;

R is selected from the group having substituents that boost electrons and substituents that attract electrons, including phenyl, p-methoxyphenyl.

The metalloporphyrin-based compound functions as a detector capable of strong coordination bonds with VOC, including CO, Cu, Fe, Mn, Ni, Cr, Zn, etc. in the center as a metal atom.

As an example, 5,10,15,20-Tetraphenyl- 21H, 23H -porphine prepared in the present invention,

5,10,15,20-Tetraphenyl- 21H, 23H -porphine cobalt (II),

5,10,15,20-Tetraphenyl- 21H, 23H- porphine copper (II),

5,10,15,20-Tetraphenyl- 21H, 23H- porphine iron (III) chloride,

5,10,15,20-Tetraphenyl- 21H, 23H- porphine manganese (III) chloride,

5,10,15,20-Tetraphenyl- 21H, 23H -porphine nickel (II),

5,10,15,20-Tetraphenyl- 21H, 23H -porphine chromium (II),

5,10,15,20-Tetraphenyl- 21H, 23H- porphine zinc (II),

5,10,15,20-Tetrakis (4-methoxyphenyl) -21H , 23H -porphine cobalt (II),

5,10,15,20-Tetrakis (4-methoxyphenyl) -21H , 23H -porphine iron (III) chloride

Etc. are mentioned, It is not limited to this.

Another element of the chemical sensor array of the present invention is a porous support that supports the dye. The porous support may be prepared from various polymers such as polyvinyllidenefluoride (PVDF), polyvinyllidenefluoride (PVDF-HFP), polysulfone (PSf), and polyacrylonitrile (PAN).

In the present invention, in order to prepare the porous support, a phase transfer process used for preparing a membrane was used (see FIG. 4). First, a polymer, for example PVDF, is dissolved in a solvent (hereinafter referred to as a first solvent) at a predetermined concentration to form a polymer solution. N-methylpyrrolidone (NMP), dimethyl acetate (DMAC), etc. may be used as the first solvent, but is not limited thereto.

In general, the ratio of the polymer and the first solvent to be used is preferably 10 to 20:80 to 90 by weight, because it is possible to form pores of a suitable size in the above range.

In a preferred embodiment of the present invention, the polymer PVDF and the first solvent NMP were used in a ratio of 15:85.

At this time, the selected first solvent should be able to mix well with the non-solvent to be used in the process (hereinafter referred to as second solvent), that is, the second solvent which cannot dissolve the polymer. As the second solvent, an organic solvent that can be mixed with water and water or a mixture thereof can be used. The polymer solution thus prepared is coated to a thickness of about 100 micrometers using a casting knife on a glass plate. The coated glass plate is immediately immersed in the prepared second solvent, water. In this way, the first solvent of the polymer solution exits the second solvent layer and fills the place where the first solvent is located, whereby the polymer is changed into a solid in a porous state to form a porous sheet.

In this case, in order to change the size and structure of the pores in the porous sheet manufactured, various experimental factors, such as polymer concentration, solvent type, and additives, may be changed. Thus, the porous supports manufactured under different conditions may be different in terms of morphology. do.

The pore size of the porous supports prepared in this way is in the range of 0.1 ~ 0.2 ㎛, the strength of the support in the above range and easy dye patterning.

The contact angles of the prepared supports were measured by using a contact angle detector to find the surface hydrophilicity of the prepared supports. As a result, it was found that PVDF-HFP was the most hydrophobic and PAN was the least hydrophobic.

In addition, as a result of examining the dye printability of the prepared four supports, it was found that the closer the surface of the retardation to the hydrophilicity, the poor the patterning result. Therefore, it was found that two types of PVDF and PVDF-HFP are preferable among the supports prepared in the present invention.

On the other hand, the sensor array of the present invention has the advantage that there is almost no color change even after 15 hours immersion in water is very stable to moisture (see Fig. 8).

In this way, the sensor array in which the chemically sensitive dye is patterned on the polymer support is added to a VOC concentration controller to input VOCs having a constant concentration (for example, 100 ppm of standard gas) to obtain an embolization image using a flatbed scanner (FIG. 9a and 9b).

Ultimately, on the basis of the data accumulation of the embolized image changed under various conditions, it is possible to find out the type of VOC or its concentration to be detected by a device capable of quantifying the degree of color change of the changed sensitive dye (FIGS. 10A and 10B). Reference). In the apparatus, the color of the sensitive dye and the color changed by VOC are converted into RGB values, and the difference is calculated to obtain DR, DG, and DB values. In this way, the change in color can be changed into a numerical change, thereby quantifying the change in color.

The present invention provides a chemical sensor array capable of coordinating with metal ions to accurately detect VOCs even at low concentrations, and is stable, portable and inexpensive because it is not affected by moisture in the air. The chemical sensor array may be widely used in the environmental industry, the food industry, the medical industry, or the cosmetic industry that handles VOCs.

Hereinafter, the configuration and operation of the present invention through the preferred embodiment of the present invention will be described in more detail. However, this is presented as a preferred example of the present invention and in no sense can be construed as limiting the present invention. Details that are not described herein will be omitted since those skilled in the art can sufficiently infer technically.

Example  One: Chemical sensitivity  Preparation of the Dye

In order to manufacture the sensor array of the present invention, the present inventors manufactured 10 kinds of metallo-porphyrine dyes having the following formula.

<Formula>

Dye 1: R = Phenyl, M = None, 5,10,15,20-Tetraphenyl- 21H, 23H -porphine

Dye 2: R = Phenyl, M = Co (II), 5,10,15,20-Tetraphenyl- 21H, 23H -porphine cobalt (II)

Dye 3: R = Phenyl, M = Cu (II) 5,10,15,20-Tetraphenyl- 21H, 23H -porphine copper (II)

Dye 4: R = Phenyl, M = Cl-Fe (III) 5,10,15,20-Tetraphenyl- 21H, 23H -porphine iron (III) chloride

Dye 5: R = Phenyl, M = Cl-Mg (III) 5,10,15,20-Tetraphenyl- 21H, 23H -porphine manganese (III) chloride

Dye 6: R = Phenyl, M = Ni (II) 5,10,15,20-Tetraphenyl- 21H, 23H -porphine nickel (II)

Dye 7: R = Phenyl, M = Cr (II) 5,10,15,20-Tetraphenyl- 21H, 23H -porphine chromium (II)

Dye 8: R = Phenyl, M = Zn (II) 5,10,15,20-Tetraphenyl- 21H, 23H -porphine zinc (II)

Dye 9: R = p-Mthoxyphenyl, M = Co (II) 5,10,15,20-Tetrakis (4-methoxyphenyl)-21H , 23H -porphine cobalt (II)

Dye 10: R = p-Mthoxyphenyl, M = Cl-Fe (III) 5,10,15,20-Tetrakis (4-methoxyphenyl) -21H , 23H -porphine iron (III) chloride

<1-1> Preparation of Dye 1 (5,10,15,20-Tetraphenyl- 21H, 23H- porphine)

Dye 1 was prepared according to the scheme below.

<Scheme 1>

Benzaldehyde (1.525ml, 0.015mol) and pyrrole _{(1.04ml, 0.015mol) CH 2 Cl} 2 Condensation reaction was carried out under (1 L) solvent conditions, and 0.4 ml of boron trifluoride etherate (2.5M solution in CH ₂ Cl ₂ ) was added as a reaction catalyst. After reacting at room temperature for one hour, the resulting porphyrinogen was added to an oxidizing solution (10 ^-2 M DDQ solution in toluene) and refluxed at 110 ° C to synthesize dye 1. The synthesized dye 1 was purified by column chromatography (CH ₂ Cl ₂ / petroleum ether = 3/1), and the yield was about 45% (1.033 g). The following is the result of NMR, IR, UV analysis to confirm the structure of the prepared dye 1.

1) H-NMR (CDCl ₃ , 500MHz) Result: δ 1.51 (s, 2H, NH), 7.24 (m, 4H, ArH), 7.75 (m, 8H, ArH), 8.20 (m, 8H, ArH)

2) IR (KBr) Absorption Peak: 3311 (pyrrole), 3056 (aromatic), 1440 (pyrrole) cm ^-1

3) UV-vis (λ _max ) result: 514nm

H-NMR spectrum, IR-spectrum and UV-visible spectrum for the prepared dye 1 are shown in FIGS. 1A-1C.

<1-2> Manufacture of dyes 2-8

Dye 2 to Dye 8 were prepared using the dye 1 prepared in <1-1> as shown in the following scheme.

<Scheme 2>

Dissolve 1 g of 5,10,15,20-Tetraphenyl- 21H, 23H -porphine (TPP) and 0.2 g of each metal salt in DMF (100 ml) solvent and reflux to synthesize various metal porphyrins (dyes 2 to 10). And the end point of the reaction was confirmed by using the UV-vis spectrum. In other words, the reaction was completed until the TPP band disappeared or no longer changed in the spectrum. Each prepared material was purified using column chromatography (CHCl ₃ elute) as in the case of the dye 1, yielding more than 95%. Each of the prepared dyes were analyzed by NMR, IR, UV as in the case of the dye 1.

1) From the results of ¹ H-NMR, the NH peak of pyrrole disappeared due to the insertion of metal into TPP, and the peaks of pyrrole and phenyl ring shifted slightly.

2) From the IR spectrum, it could be observed that the NH peak of the pyrrole that appeared in 3311cm ^-1 disappeared due to the metal insertion.

3) UV-vis (λ _max , dyes 2-8): each dye showed different λ _max as follows; (Dye 2) 523 nm, (Dye 3) 540 nm, (Dye 4) 570 nm, (Dye 5) 620 nm, (Dye 6) 528 nm, (Dye 7) 514 nm, (Dye 8) 549 nm.

The change of IR shown when dye 6 was prepared by the method shown in <1-1> is shown in FIG. 2. According to this, the metal ions are introduced into the dye 1 to form a bond between the metal and the amine, and as a result, the NH bond of the dye 1 disappears from the FTIR spectrum as the dye 6 is changed. It was found to be well prepared.

<1-3> Preparation of dyes 9 and 10

Dye 9 and dye 10 were synthesized according to the following scheme.

<Scheme 3>

Using p-Methoxybenzaldehyde and pyrrol, 5,10,15,20-Tetra-p-methoxyphenyl- 21H, 23H- porphine (p-OMe-TPP) prepared under the reaction conditions described in the above preparation method of dye 1 was prepared. Dyes 9 and 10 were prepared. Dyes 9 and 10 can be prepared by reacting p-OMe-TPP, which has the same basic porphyrine structure as Dye 1, with p-Methoxy group as R group, in metal (Co, Fe) chloride and DMF solution as shown above. Could. The end point of the reaction was determined through the UV-vis spectrum of the reactants as in the synthesis of dyes 2-8. The prepared dyes 9 and 10 were purified by column chromatography (CHCl ₃ elute), yields of more than 95% can be obtained. The NMR, IR and UV analysis of the prepared dyes 9 and 10 are as follows:

1) The CH ₃ peak of the ρ-methoxyphenyl group was confirmed at δ 5.18 by ¹ H-NMR.

2) From 2830㎝ ^-1 through FTIR spectrum The peak of CH ₃ was confirmed and the peak of PhOC was confirmed at 1242 cm <^-1> . In addition, unlike the previously synthesized materials, dyes 9 and 10 substituted methoxy groups in the para position, and thus they showed ring substitution patterns between 1800 and 2000 cm ^-1 .

3) UV-vis (λ _max ): (dye 9) 531 nm, (dye 10) 510 nm

3 is the FTIR spectrum of Dye 9, compared to that of Dye 6.

Example  2: Preparation and Analysis of Porous Supports

<2-1> Preparation of Porous Support

In this study, asymmetric porous sheets were fabricated using various polymers (PVDF, PVDF-HFP, PSf, PAN, etc.) to prepare a support suitable for manufacturing Colorimetric Sensor Array.

Each polymer material (PVDF, PVDF-HFP, PSf, PAN) was dissolved in NMP to prepare a solution having a polymer / solvent composition of 15/85 wt.%, Which was present in the solution prepared through filtration and degassing. Bubbles and impurities were removed. After a certain amount of the solution was poured on a leveled PET nonwoven fabric, it was cast to a certain thickness using a film forming knife (YBA-5, Yoshimitsu, Japan), and then immersed in ultrapure water to prepare a polymeric porous support having an asymmetric structure. The prepared support was treated in hot water at about 50 ° C. for at least 2 hours, and NMP remaining in the support was completely removed during the hydrothermal treatment. The thus prepared support was washed several times with ultrapure water and examined the SEM photographs, contact angles, etc. to find out the properties of the prepared support.

5 is a FESEM photograph of porous supports prepared using PVDF, PVDF-HFP, PSf and PAN.

<2-2> Pore size investigation of porous support

5 is a FESEM photograph of porous supports prepared using PVDF, PVDF-HFP, PSf and PAN.

As shown in FIG. 5, it can be seen that different polymers have different pore sizes and surface morphologies, and the characteristics of these supports will affect the fabrication of the colorimetric sensor array.

6 is a distribution diagram of the pore sizes of these supports and the results measured using Permporometry. From the above results, the order of pore size was PVDF-HFP> PVDF> PSf> PAN. It was found that the pore size consisted of pores of 0.2 micrometer or less.

<2-3> Measurement of surface hydrophilicity of supports

The contact angles of the prepared supports were measured by using a contact angle detector in order to determine the surface hydrophilicity of the prepared supports. The results are as follows.

The above results show that PVDF-HFP has the highest hydrophobicity and the smallest PAN.

<2-4> Manufacturing suitability (print suitability) investigation of colorimetric sensor array of porous supports

Among the prepared supports, the print suitability of the dyes 1 to 10 was examined to find the most suitable for producing the Colorimetric Sensor Array.

7 is a result of patterning the sensitive dye of the present invention on PVDF, PVDF-HFP, PSf support. Patterning of the dye shown in Figure 7 is a method of preparing a solution to a concentration of 50 mmol in the chlorobenzene 10 dyes prepared, and the sensitive dye solution prepared in this way by dropping the surface of the support prepared by 1 μl using a micro-syringe Patterned with to form a round spots.

Looking at the above results it can be seen that the closer the surface of the support to the hydrophilic patterning results are poor. Therefore, among the supports prepared in this study, two types of PVDF and PVDF-HFP were found to be very suitable.

Example 3 Investigation of Color Change of Dye by VOCs

<3-1> VOCs Concentration Control System

Sensitive dyes prepared in the present invention will change color under various concentration conditions of various types of VOCs. VOCs concentration regulator that can produce various concentrations of VOC can be configured as shown in the diagram below.

1. Connect the span gas, zero gas and out lines to the reactor on each of the four lines of the diluter and install the last vent line.

2. Turn on the diluter and set the span gas and zero gas to 0.25MPa and 0.4MPa respectively. At this time, the pressure of zero gas is maintained higher than the pressure of span gas.

<3-2> Sensitive Dye Color Change by VOCs

In order to investigate the color change by VOCs of 10 sensitive dyes prepared in this study, we constructed a VOCs concentration control device as described in <3-1> and examined dye color changes at various concentrations of various VOCs.

Table 2 shows the sensitive dye colors at standard concentrations (100 ppm) of various VOCs. According to this, it can be seen that the color of the dye itself at 0.0 ppm of VOC is changed depending on the type of VOC contacted.

Specifically, dyes 1 to 10 were dissolved in dichloromethane at a concentration of 10 mmol, patterned on a PVDF support, and then dried in a 50 ° C. vacuum oven for 1 hour to remove the solvent. The solvent was removed and only the pure dye patterned support was placed in a laboratory designed device and exposed to VOCs such as DMF, pyridine, CHCl ₃ , THF, acetic acid. At this time, VOCs were used as a standard gas of 100ppm concentration, and embolization images were obtained through a flatbed scanner (HP officejet 6110).

<3-3> Effect of Dye Color Change by Water

After coating a dye having a concentration of 50 mmol (solvent: chlorobenzene) on the PVDF porous support, the dye was patterned on the support by vacuum drying at about 40 to 50 ° C. for 1 hour to completely remove the solvent included in the dye. In order to examine the effect of moisture on the sensor array thus manufactured, the color change was examined while soaking in the prepared distilled water for 15 hours. FIG. 8 shows the pattern A of the sensor array in the water zero state (before dipping into distilled water) and the sensor array pattern B after soaking in distilled water for 15 hours.

As shown in FIG. 8, it can be seen that the sensitive dye of the present invention is not affected by moisture, even after 15 hours of immersion in distilled water, and this phenomenon was found to be the same even after patterning.

While the embodiments of the present invention have been described with reference to the accompanying tables, the present invention is not limited to the above embodiments, but may be embodied in various forms, and a person of ordinary skill in the art to which the present invention pertains. It will be appreciated 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.

FIG. 1A is an H-NMR spectrum of Dye 1 prepared according to one embodiment of the present invention, FIG. 1B is an IR-spectrum of Dye 1, and FIG. 1C is a UV-Visible spectrum of Dye 1. FIG.

2 is the FTIR spectrum of Dye 1 and Dye 6.

3 is the FTIR spectra of Dyes 6 and Dyes 9.

Figure 4 is a schematic diagram of the phase change process used to prepare a porous support according to an embodiment of the present invention.

5 are FESEM photographs of the surface of the porous support prepared using PVDF, PVDF-HFP, PSf and PAN according to one embodiment of the present invention.

6 is a distribution diagram showing the distribution of pore sizes of porous supports prepared using PVDF, PVDF-HFP, PSf, and PAN according to an embodiment of the present invention.

7 is a photograph showing the results of patterning the dyes 1 to 10 of the present invention on each support prepared using PVDF, PVDF-HFP, PSf and PAN according to an embodiment of the present invention.

FIG. 8 shows the pattern A of the sensor array in the water zero state (before dipping in distilled water) of the sensor array manufactured according to the embodiment of the present invention and the sensor array pattern B after soaking in distilled water for 15 hours.

Figure 9 is a photograph showing the dye color change before and after exposure of the sensor array manufactured according to an embodiment of the present invention to various VOC (color image was measured with a flatbed scanner (hp officejet 6110), VOC concentration is N ₂ Of 50 ppm).

FIG. 10A is a schematic diagram of a color change quantification device, and FIG. 10B illustrates a color change measurement principle (designed based on 45 ° / 0 ° geometry, which is a reflection color measurement principle of the International Illumination Committee).

Claims (6)

A chemical sensor array for detecting a volatile organic compound (VOC) comprising at least one chemoresponsive dye and a polymeric porous support supporting the same. The sensor array of claim 1, wherein the chemically sensitive dye reacts with the VOC to cause a color change. The sensor array of claim 1, wherein the VOC is selected from the group consisting of amines, aldehydes, acids, ethers, esters, alcohols, arenes and halocarbons. The sensor array of claim 1, wherein the chemically sensitive dye comprises a compound having the formula: <Formula>

Wherein M is selected from the group consisting of CO, Cu, Fe, Mn, Ni, Cr and Zn; R is phenyl or p-methoxyphenyl. The sensor array of claim 1, wherein the polymeric porous support is a hydrophobic polymer selected from the group consisting of PVDF, PVDF-HFP, PSf, and PAN. A method of detecting volatile organic compounds (VOCs) using the sensor array of claim 1.

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