CN113880867B - Detectable Cu in water 2+ 、Zn 2+ Molecular sensor and application - Google Patents

Abstract

The invention provides a kind of foodDetection of Cu in Water ²⁺ 、Zn ²⁺ Molecular sensor and application relate to organic function material detection technical field. The molecular sensor provided by the invention is prepared by taking 1, 7-tetramethyl-8-hydroxy-9-julolidine aldehyde and p-phenylenediamine as reaction raw materials through one-step polymerization reaction; the molecular sensor simultaneously contains three ionic action sites of rigid fatty naphthenoamine, imine and hydroxyl, and the coordination of the dual sites of imine and ortho-phenol hydroxyl has stronger coordination capability to metal ions, so that the dual sites of imine and ortho-phenol hydroxyl are coordinated to Cu ²⁺ 、Zn ²⁺ The ions show sensitive fluorescence reduction, enhance detection signals, have high sensitivity and good selectivity, and have remarkable application value; the preparation method has the advantages of high yield, simple synthesis process, easy implementation and the like, is suitable for industrial popularization, and creates favorable conditions for popularization and application of the molecular sensor.

Description

A molecular sensor capable of detecting Cu2+ and Zn2+ in water and its application

technical field

The invention relates to the technical field of organic material function detection, in particular to a molecular sensor capable of sensitively detecting Cu ²⁺ and Zn ²⁺ ions in water and its application.

Background technique

With the rapid development of the global economy, the pollution of water resources has become more and more serious, especially the heavy metal pollution in water resources. Heavy metal pollution has the characteristics of concealment, long-term, accumulation and irreversibility. In addition, heavy metals are highly toxic and easy to accumulate and expand in the biological chain. Therefore, heavy metal pollution in water resources has largely endangered the ecological environment and human survival and development. After irrigating the land with sewage with excessive heavy metal content, it will not only lead to the decline of crop yield and quality, but even cause the plants to wither and die; while the heavy metals entering the soil cannot be decomposed or disappeared, but are easily absorbed by organisms, causing food contamination . When human beings ingest water and food with high content of heavy metal ions, the human body cannot metabolize and degrade them. Accumulation to a certain extent can lead to chronic poisoning, low immunity, dysfunction, cancer and a series of diseases, even life-threatening. For example, copper is an essential trace element for animals, plants and humans. Trace amounts of copper can promote the growth of animals and plants, but when a certain amount of copper ions is accumulated in the organism, it can lead to metabolic disorders, liver cirrhosis, liver ascites and even more serious; Zinc is an important element involved in immune function, but excessive zinc can inhibit the activity and bactericidal power of phagocytes, reduce the immune function of the human body, weaken the ability to resist diseases and increase the susceptibility to diseases, etc. Therefore, the development of fast, convenient and sensitive detection methods for heavy metal ions in water is of great significance to the fields of industrial and agricultural production, environmental science and so on.

At present, in the field of detection of heavy metal ions in water, inductively coupled plasma method, atomic fluorescence spectrometry, atomic absorption spectrometry, etc. have been widely used. However, samples of this type of detection method generally require special treatment, and the required detection is time-consuming. Through ingenious design, the fluorescent molecular sensor converts the molecular recognition information occurring in the microcosmic world into an optical signal that is easy to detect, and performs real-time detection at the molecular level. It has the characteristics of high sensitivity, good selectivity, and easy operation. more and more widely used. Based on different optical signal conversion mechanisms, a large number of metal ion fluorescent molecular sensors with different functions have been developed and prepared. However, at present, most fluorescent molecular sensors only have a sensitive detection function for a specific metal ion. The function is relatively single, and the application limitations are relatively large, which is difficult to meet the growing market demand.

The julonidine group has the characteristics of highly conjugated rigid coplanar structure, good optical properties, and strong complexation performance for metal ions, and is an excellent molecular sensor building unit [TGJo, YJNa, *JJLee, MMLee, SYLee,C.Kim,NewJ.Chem.,2015,39,2580]; Enol tautomerization between the imine group of Schiff base compound and the adjacent phenolic hydroxyl group can increase the sensitivity of the molecular sensor, making it compatible with metal Ultrasensitive spectral signal changes after ion interaction [J. Zhang, Z. Zhao, H. Shang, Q. Liu, F. Liu, New J. Chem., 2019, 43, 14179]. But at present, fluorescent molecular sensors constructed with tetramethyljulolidine-phenylenediamine and capable of detecting Cu ²⁺ and Zn ²⁺ ions in water have not been developed yet.

Contents of the invention

The technical purpose of the present invention is to provide a tetramethyljulolidine-phenylenediamine fluorescent molecular sensor which has different optical detection signals for Cu ²⁺ and Zn ²⁺ ions and is easy to prepare.

Another technical purpose of the present invention is to provide a technical method capable of sensitively detecting Cu ²⁺ and Zn ²⁺ ions in different types of water. The technical method has the advantages of sensitivity, rapidity, simplicity and easy operation.

In order to realize the above-mentioned technical purpose, the present invention adopts following technical scheme:

A tetramethyljulonidine-phenylenediamine fluorescent molecular sensor with different optical detection signals for Cu ²⁺ and Zn ²⁺ ions, the molecular structure of which is:

A tetramethyljulolidine-phenylenediamine fluorescent molecular sensor with different optical detection signals for Cu ²⁺ and Zn ²⁺ ions, the preparation method of which is as follows:

Put αmmol of 1,1,7,7-tetramethyl-8-hydroxy-9-julonidine aldehyde into a round-bottomed flask filled with βmL of absolute ethanol, heat up to reflux, and then put δmmol of p-benzene Diamine, γμL glacial acetic acid; Continue to react for 3-5 hours; After the reaction mixture is filtered, washed with absolute ethanol, and dried, a tan tetramethyljulolidine-phenylenediamine fluorescent molecular sensor is obtained; α:β: γ:δ is 2:25:1:200.

The preparation reaction formula of tetramethyljulolidine-phenylenediamine fluorescent molecular sensor is:

The present invention has the following technical effects: the tetramethyljulolidine-phenylenediamine fluorescent molecular sensor simultaneously contains three ion interaction sites of rigid aliphatic cycloalkylamine, imine and hydroxyl, and the imine and adjacent phenolic hydroxyl The dual-site synergy has a strong coordination ability for metal ions, so that it exhibits significantly different optical detection signals for Cu ²⁺ and Zn ²⁺ ions, and has high sensitivity, fast response, and high application value; the present invention The preparation process of the fluorescent molecular sensor provided has the advantages of high yield, mild synthesis conditions, and simple preparation process, which is suitable for industrial implementation and creates favorable conditions for the popularization and application of the tetramethyljulonidine-phenylenediamine fluorescent molecular sensor .

Description of drawings

Fig. 1 is the NMR spectrum of the compound obtained in Example 1-2.

Fig. 2 is the fluorescent emission performance of the tetramethyljulolidine-phenylenediamine fluorescent molecular sensor after adding different metal ions in 95% DMSO distilled aqueous solution.

Fig. 3 is the fluorescent emission performance of the tetramethyljulolidine-phenylenediamine fluorescent molecular sensor after adding different metal ions in 95% DMF distilled aqueous solution.

Fig. 4 is the fluorescence emission spectrum of tetramethyljulolidine-phenylenediamine fluorescent molecular sensor in 95% DMSO distilled aqueous solution while adding 10 times of Zn ²⁺ /Cu ²⁺ and other different metal ions.

Detailed ways

A tetramethyljulolidine-phenylenediamine fluorescent molecular sensor with different optical detection signals for Cu ²⁺ and Zn ²⁺ ions disclosed by the present invention has a molecular structure of:

It can be prepared by one-step polymerization using 1,1,7,7-tetramethyl-8-hydroxy-9-julonidine aldehyde and p-phenylenediamine as raw materials. The synthesis reaction formula is:

Example 1

Preparation of Compound A: Put 2mmol of 1,1,7,7-tetramethyl-8-hydroxy-9-julonidine aldehyde into a round-bottomed flask filled with 25mL of absolute ethanol, heat up to reflux and then add 1 mmol of p-phenylenediamine and 200 μL of glacial acetic acid were continued to react for 3 hours; the reaction mixture was filtered, washed with absolute ethanol, and dried to obtain 295.8 mg of tan compound A with a yield of 47.8%.

Example 2

Preparation of Compound B: Put 2mmol of 1,1,7,7-tetramethyl-8-hydroxy-9-julonidine aldehyde into a round-bottomed flask filled with 25mL of absolute ethanol, heat up to reflux and then add 1 mmol of p-phenylenediamine and 200 μL of glacial acetic acid were continued to react for 5 hours; the reaction mixture was filtered, washed with absolute ethanol, and dried to obtain 296.4 mg of tan compound B with a yield of 48%.

Compounds A and B respectively obtained in Examples 1 and 2 were analyzed and determined, and the H NMR spectra of the two were consistent, and the data were as follows: In ¹ HNMR (CDCl ₃ , 400MHz), there were 2 OH proton signal peaks: 13.51 (s ,2H); 2 proton signal peaks on C=N-carbon: 8.33(s,2H); 6 aromatic ring proton signal peaks: 7.02(m,4H), 6.74(s,2H); 16 CH ₂ - Proton signal peaks: 3.24 (d, 8H), 1.96 (d, 8H); 24 CH ₃ - proton signal peaks, 1.33 (s, 12H), 1.26 (s, 12H), and tetramethyljulonidine -Phenylenediamine fluorescence molecular theoretical value is basically the same. Thus, it can be confirmed that the molecular structures of compounds A and B are:

即四甲基久洛尼定-苯二胺荧光分子。

That is, tetramethyljulolidine-phenylenediamine fluorescent molecule.

Example 3

Fluorescence detection performance of tetramethyljulolidine-phenylenediamine fluorescent molecular sensor for different metal ions in 95% DMSO distilled water: In 95% DMSO distilled water, the concentration of tetramethyljulonidine-phenylenediamine is 1×10 ^-5 mol/L The methyljulolidine-phenylenediamine fluorescent molecular sensor has a maximum fluorescence emission peak at 543nm; after adding 10 times the equivalent of Zn ²⁺ , its maximum fluorescence emission intensity at 543nm increases by 2.4 times; after adding Cu ²⁺ , its maximum fluorescence emission at The maximum fluorescence emission peak at 543nm is almost quenched; other metal ions such as Al ³⁺ , Fe ³⁺ , Hg ²⁺ , Co ²⁺ , Mn ²⁺ , Ni ²⁺ , Cd ²⁺ , Li ⁺ , Na ⁺ After the addition of , K ⁺ , Ba ²⁺ , Ca ²⁺ , Mg ^{2+ ,} etc., the maximum fluorescence emission of the compound molecule at the position of 543nm has almost no obvious change. These indicated that the tetramethyljulolidine-phenylenediamine fluorescent molecular sensor has significantly different fluorescent signal responses to Cu ²⁺ and Zn ²⁺ ions, and has the potential to identify these two metal ions.

Example 4

Fluorescence detection performance of tetramethyljulolidine-phenylenediamine fluorescent molecular sensor for different metal ions in 95% DMF distilled water solution: In 95% DMF distilled water solution, tetramethyljulonidine with a concentration of 1×10 ^-5 mol/L The methyljulonidine-phenylenediamine fluorescent molecular sensor has a maximum fluorescence emission peak at 540nm; after adding 10 times the equivalent of Zn ²⁺ , its maximum fluorescence emission intensity at 540nm increases by 9.5 times; after adding Cu ²⁺ , Its maximum fluorescence emission peak at 540nm is almost quenched; other metal ions such as Al ³⁺ , Fe ³⁺ , Hg ²⁺ , Co ²⁺ , Mn ²⁺ , Ni ²⁺ , Cd ²⁺ , Li ⁺ , After adding Na ⁺ , K ⁺ , Ba ²⁺ , Ca ²⁺ , Mg ^{2+ ,} etc., the maximum fluorescence emission of the compound molecule at the position of 540nm has almost no obvious change. These indicated that the tetramethyljulolidine-phenylenediamine fluorescent molecular sensor has different fluorescence recognition potentials for Cu ²⁺ and Zn ²⁺ ions.

Example 5

Tetramethyljulonidine-Phenylenediamine Fluorescent Molecular Sensor Selective Competitive Performance for Zn ²⁺ /Cu ²⁺ and Other Metal Ions: Tetramethyljulonidine at a Concentration of 1×10 ^-5 mol/L -Phenylenediamine fluorescent molecular sensor is added 10 times the equivalent of Zn ²⁺ and other metal ions such as Al ³⁺ , Fe ³⁺ , Hg ²⁺ , Co ²⁺ , Mn ²⁺ , Ni ²⁺ , Cd ²⁺ , Li ⁺ , Na ⁺ , K ⁺ , Ba ²⁺ , Ca ²⁺ , Mg ²⁺ . The fluorescence emission spectrum research of the mixed system shows that after adding 10 times the equivalent of Zn ²⁺ to the fluorescent molecular sensor of tetramethyljulolidine-phenylenediamine, its fluorescence emission at 543nm is enhanced; when Al ³⁺ , Fe ³⁺ , Add metal ions ^such as Hg ²⁺ , Co ²⁺ , Mn ²⁺ , Ni ²⁺ , Cd ²⁺ , Li ⁺ , Na ⁺ , K ⁺ , Ba ²⁺ , Ca ²⁺ , Mg ²⁺ and Zn ²⁺ simultaneously After the methyljulolidine-phenylenediamine fluorescent molecular sensor solution, the fluorescence emission spectrum of the mixed system is close to the fluorescence of the tetramethyljulolidine-phenylenediamine fluorescent molecular sensor-Zn ²⁺ system. Similarly, 10 times the equivalent of Cu ^{2 +} and Al ³⁺ , Fe ³⁺ , Hg ²⁺ , Co ²⁺ , Mn ²⁺ , Ni ²⁺ were added to the tetramethyljulonidine-phenylenediamine fluorescent molecule solution at the same time. , Cd ²⁺ , Li ⁺ , Na ⁺ , K ⁺ , Ba ²⁺ , Ca ²⁺ , Mg ²⁺ and other metal ions, the fluorescence of the mixed system and the fluorescent molecular sensor of tetramethyljulolidine-phenylenediamine- The fluorescence of Cu ²⁺ system is similar. These indicated that even when Zn ²⁺ , Cu ²⁺ coexisted with other metal ions, the tetramethyljulolidine-phenylenediamine fluorescent molecular sensor showed good selective detection performance for Zn ²⁺ , Cu ²⁺ .

Example 6

Actual detection performance of tetramethyljulonidine-phenylenediamine fluorescent molecular sensor for Cu ²⁺ and Zn ²⁺ ions in river water and tap water: two water samples were collected from Tuhai River and tap water in Dezhou area, and pretreated by membrane Remove the suspended matter, and confirm that there is no Cu ²⁺ , Zn ²⁺ in the water sample taken by atomic absorption spectrometry; then add Mg ²⁺ , Ca ²⁺ , Li ⁺ , Na ⁺ and K ⁺ ( 10.00 μM) to prepare synthetic water, and then continue to add different amounts of Cu ²⁺ and Zn ²⁺ , and calculate the reproducibility rate by fluorescence test. The results are shown in the table below, the reproducibility rate of the tetramethyljulolidine-phenylenediamine fluorescent molecular sensor for Cu ²⁺ is 101%-102%, and the reproducibility rate for Zn ²⁺ is 99%-102%, Within the allowable error range; it shows that the tetramethyljulonidine-phenylenediamine fluorescent molecular sensor has high accuracy and broad application prospects for the analysis and detection of Cu ²⁺ and Zn ²⁺ in actual water samples.

Table 1 The actual detection performance of tetramethyljulonidine-phenylenediamine fluorescent molecular sensor for copper and zinc ions in tap water or river water

^a n=3; ^b add Mg ²⁺ , Ca ²⁺ , Li ⁺ , Na ⁺ and K ⁺ (10.00 μM) river water or tap water; test conditions: 10 μM tetramethyljulolidine-phenylenediamine fluorescent molecular sensor in DMF-river water/tap water (19:1) mixed solvent.

Claims (2)

1. Detectable Cu in water ²⁺ 、Zn ²⁺ The molecular structure of the molecular sensor is as follows:

2. a detectable Cu in water as claimed in claim 1 ²⁺ 、Zn ²⁺ In detecting Cu in water ²⁺ 、Zn ²⁺ Application in ions.

Images