阅读说明：本技术 一种钯离子探针及其制备方法和应用 (Palladium ion probe and preparation method and application thereof ) 是由 蔡林涛 刘闯军 向晶晶 周理华 龚萍 于 2019-10-21 设计创作，主要内容包括：本发明公开了一种钯离子探针及其制备方法和应用,具体是将Cy7-Cl、二(2-甲基吡啶)胺和三乙胺在有机溶剂中充分反应,反应期间溶液颜色从绿色变为蓝色；反应完毕后产物用二氯甲烷和水萃取,将二氯甲烷层干燥后旋蒸后得到蓝色产物即为钯离子探针。本发明制备的钯离子探针属于比率型钯离子探针,其具备抗干扰性,检测精度高。能够用于对环境、生物体内微量甚至痕量钯离子的检测。(The invention discloses a palladium ion probe and a preparation method and application thereof, and particularly relates to a method for fully reacting Cy7-Cl, di (2-methylpyridine) amine and triethylamine in an organic solvent, wherein the color of a solution is changed from green to blue during the reaction; and after the reaction is finished, extracting the product by using dichloromethane and water, drying a dichloromethane layer, and then carrying out rotary evaporation to obtain a blue product, namely the palladium ion probe. The palladium ion probe prepared by the invention belongs to a ratio type palladium ion probe, and has anti-interference performance and high detection precision. Can be used for detecting trace palladium ions in the environment and organisms.)

1. A palladium ion probe having a structural formula represented by the following formula 1:

2. the palladium ion probe of claim 1, wherein I in formula 1^-Ions may be substituted for F^-、Cl^-、Br^-The palladium ion probe is a ratiometric fluorescent probe.

3. The method for preparing a palladium ion probe according to any one of claims 1 to 2, wherein the method comprises the following steps:

the method specifically comprises the following steps: fully reacting Cy7-Cl, di (2-methylpyridine) amine and triethylamine in an organic solvent, wherein the color of the solution changes from green to blue during the reaction; after the reaction is finished, cooling the reaction system, extracting with dichloromethane and water, drying a dichloromethane layer, removing the solvent by rotary evaporation, and passing through a column to obtain a blue product, namely the compound 1.

4. The method of claim 3, wherein the organic solvent is selected from N, N-Dimethylformamide (DMF).

5. The production method according to claim 3, characterized in that: the reaction temperature is 40 ℃, and the reaction time is 3-8 hours, preferably 5-6 hours.

6. The production method according to claim 3, characterized in that: the molar ratio of Cy7-Cl, bis (2-methylpyridine) amine and triethylamine was 1: 1: 1.

7. the production method according to any one of claims 3 to 6, characterized in that: the amount of the organic solvent was 10ml/1mmol of Cy 7-Cl.

8. The production method according to any one of claims 3 to 6, characterized in that: the volume ratio of the dichloromethane to the water in the extraction is 1: 10.

9. the production method according to any one of claims 3 to 6, characterized in that: the extracted dichloromethane layer was dried over anhydrous magnesium sulfate.

10. Use of the palladium ion probe according to any one of claims 1 to 2 or the palladium ion probe prepared by the preparation method according to any one of claims 3 to 6, wherein: the palladium ion probe is used for qualitative or quantitative detection of palladium ions in the environment or organism.

11. Use according to claim 10, characterized in that: the method for detecting metal palladium ions by using the palladium ion probe comprises the step of adding Pd²⁺Is added into the palladium ion probe solution, and then the color change and/or the color change of the system are visually observedThe system was tested for uv absorption change.

12. Use according to claim 11, characterized in that: the palladium ion probe solution adopts a mixed solvent of water and an organic solvent.

13. Use according to claim 12, characterized in that: the organic solvent is selected from dimethyl sulfoxide (DMSO).

14. Use according to claim 12 or 13, characterized in that: the volume ratio of the water to the organic solvent is 995:5 to 990: 10.

Technical Field

The invention belongs to the technical field of molecular probes, relates to a palladium ion probe and preparation and application thereof, and particularly relates to a ratio type palladium ion fluorescent probe and a preparation method and application thereof.

Background

Heavy metals play an important role in science such as physics, chemistry and environment, and palladium metal is widely used in various industries due to its special physicochemical properties. However, the use of palladium in large quantities inevitably causes the palladium to remain in the environment, causing the problem of heavy metal pollution to the environment and the problem of human health. Therefore, detection of palladium ions is particularly important. Researchers have found that the maximum daily body intake of healthy people should be less than 15 μ g. In the pharmaceutical industry, the specified value of the residual amount of palladium in the medicine is 5-10 mg/kg. The discharge of a large amount of supported palladium and compounds thereof can quickly improve the content of palladium in different environments such as soil, vegetation, rivers, oceans and the like, an organism takes excessive palladium intake through food chain enrichment effect, and the absorbed palladium is quickly transported to organs such as liver, kidney, spleen and the like, thus causing very serious harm to the body. The research proves that the palladium ions in vivo have the effect after being combined with biomacromolecules such as amino acid, protein, DNA, vitamin B6 and the like, and disturb the normal signal conduction, physiological activity and other processes of cells. The chances of macroscopic symptoms manifesting asthma, hair loss, miscarriage, nausea and other serious physical ailments increase. In addition, for those who are susceptible to infection, severe allergic reactions can be caused even with very low palladium ion invasion.

Palladium ions are present in very low levels in samples of water, soil and sediment, and so it is difficult to detect them accurately. Although conventional detection methods (inductively coupled plasma, atomic absorption spectroscopy, atomic emission spectroscopy, high performance liquid chromatography, etc.) can achieve high measurement accuracy, they require expensive instrumentation and running costs, as well as specialized operating technicians. In addition, in the conventional detection method, a complicated pretreatment of the sample is required in order to avoid contamination or damage to the instrument. In summary, these factors will greatly limit the wide application of conventional instruments in daily testing. Therefore, the construction of a method for quantitatively detecting palladium with high efficiency, high selectivity, high sensitivity and short time response is a problem to be solved urgently at present.

In comparison, the fluorescence probe method of palladium ions can not only overcome the defects of the traditional method, but also quickly and accurately respond to objects. Therefore, this detection method has been receiving attention from researchers in recent years. However, the fluorescence probe method still has the disadvantages of poor penetration and low resolution, so that the application of the method in the living body is limited. Photoacoustic imaging (PA) is a novel optical imaging technology developed in recent years, combines the advantages of optical imaging and ultrasonic imaging, shows high-resolution and high-contrast imaging capability on deep tissues, and shows a wide clinical application prospect. Most of the reported palladium ion probes are 'turn-on' type fluorescent probes. The turn-on type fluorescent probe depends on the change of a single emission peak when detecting palladium ions and is easily influenced by the efficiency, light scattering and microenvironment of an instrument. In comparison, the ratiometric fluorescent probe can detect the object to be detected by measuring the change of the ratio of the two emission peaks, and can avoid the interference to a certain extent, so that the palladium ions in the biological sample can be tracked and quantified more accurately. To solve the problems encountered so far and based on the above analysis, the present proposal designs and develops a highly sensitive and highly selective photoacoustic ratio type palladium ion probe.

Disclosure of Invention

Aiming at the problems of complex operation, low accuracy and the like of the existing palladium ion detection method, the invention designs and develops the high-sensitivity and high-selectivity photoacoustic ratio type palladium ion probe. So as to realize accurate and convenient measurement of the qualitative and quantitative determination of the palladium ions.

The invention discloses a palladium ion probe, which has a structural formula shown as the following formula 1:

i in formula 1^-Ions may be substituted for F^-、Cl^-、Br^-。

Further, the palladium ion probe is a ratiometric fluorescent probe.

The invention also relates to a preparation method of the palladium ion probe compound 1, which specifically adopts the following route:

further, the method specifically comprises the following steps: fully reacting Cy7-Cl, di (2-methylpyridine) amine and triethylamine in an organic solvent, wherein the color of the solution changes from green to blue during the reaction; after the reaction is finished, cooling the reaction system, extracting with dichloromethane and water, drying a dichloromethane layer, removing the solvent by rotary evaporation, and passing through a column to obtain a blue product, namely the compound 1. Wherein triethylamine is added as a base for promoting the reaction, and the function of the triethylamine is to deprotonate DPA and simultaneously neutralize HCl generated in the reaction process to promote the forward direction of the reaction.

Further, the organic solvent is selected from N, N-Dimethylformamide (DMF).

Further, the reaction temperature is 35-50 ℃, preferably 40 ℃, and the reaction time is 3-8 hours, preferably 5-6 hours.

Further, the molar ratio of Cy7-Cl, bis (2-methylpyridine) amine and triethylamine is (1-2): (1-2): 1, preferably 1: 1: 1.

further, the amount of the organic solvent was 10ml/1mmol of Cy 7-Cl.

Further, the volume ratio of the dichloromethane to the water in the extraction is (1-2): 10, preferably 1: 10.

Further, the extracted dichloromethane layer was dried over anhydrous magnesium sulfate.

In addition, the invention also relates to application of the palladium ion probe, and particularly relates to the application of the palladium ion probe in qualitative or quantitative detection of palladium ions in environment or organisms.

Further, the method for detecting metal palladium ions by using the palladium ion probe comprises the step of containing Pd²⁺Is added to the palladium ion probe solution and then the change in color of the system and/or the change in uv absorption of the system is visually examined.

Further, the palladium ion probe solution adopts a mixed solvent of water and an organic solvent.

Further, the organic solvent is selected from dimethyl sulfoxide (DMSO).

Further, the volume ratio of the water to the organic solvent is 997:3 to 980:20, preferably 995:5 to 990: 10.

The invention has the beneficial effects that:

1. the palladium ion probe is a compound 1 which takes cyanine as a fluorescent group and takes di (2-methylpyridine) amine (DPA) as a recognition group. The compound 1 can selectively identify palladium ions and is not interfered by other metal ions.

2. With the addition of palladium ions, the blue color of the compound 1 solution is changed into green color, the fluorescence of the solution at 770nm is gradually weakened, the fluorescence at 800nm is gradually enhanced, the absorption at 710nm is gradually reduced, and the absorption at 770nm is continuously increased. Meanwhile, the photoacoustic signal at 770nm is gradually weakened, and the photoacoustic signal at 860nm is gradually strengthened. The coordination ratio of the compound 1 to palladium ions was 1: 1.

3. The palladium ion probe provided by the invention has excellent high selectivity on palladium ions, can selectively identify the palladium ions, and can be combined with the palladium ions to change the change of the fluorescence absorption wavelength of the solution.

4. The palladium ion probe of the invention shows excellent high sensitivity to palladium ions, and Pd is treated by the compound 1²⁺The uv-visible titration experiments of (a) can find that a solution of compound 1 has uv-visible absorption intensity at λ 710nm and λ 770nm both in comparison with Pd²⁺Has a good linear relationship in the range of 0-0.28 equivalents. Calculating the Pd of the probe pair according to the calculation formula of the detection limit DL of 3s/k specified by the International Union of Pure and Applied Chemistry (IUPAC) by a fitted linear equation²⁺Detection limit ofIt was 39.29 nM. Shows that the probe compound 1 has high sensitivity and can be used for Pd²⁺Trace detection of (2).

Description of the drawings:

the invention is described in detail below with reference to the drawings and the detailed description;

FIG. 1 is a graph showing the UV absorption of 25. mu.M probe compound 1 solution after adding 1.0 equivalent of each of different metal ions.

FIG. 2 shows the fluorescence ratio F/F0 at 770nm of a 25. mu.M probe compound 1 solution after adding 1.0 equivalent of each of different metal ions (F is the fluorescence value of compound 1, and F0 is the fluorescence value after adding different metal ions).

FIG. 3 shows Pd in different concentrations²⁺UV-visible absorption intensity curve for 25. mu.M probe compound 1 solution.

FIG. 4 includes FIG. 4(a), FIG. 4(b) and FIG. 4(c), each being Pd²⁺UV-visible titration curves at 700nm, 770nm and 860nm wavelength for 25 μ M probe compound 1 solution.

FIG. 5 d of different concentrations²⁺Fluorescence intensity curve at 770nm for 25 μ M probe compound 1 solution.

FIG. 6 d of different concentrations²⁺Fluorescence intensity curve at 800nm for 25. mu.M probe compound 1 solution.

FIG. 7 addition of Compound 1 solution and Pd to mice²⁺Graph of changes in photoacoustic signal.

FIG. 8Pd²⁺Titration curves of photoacoustic signal at 860nm for 25 μ M probe compound 1 solution.

Detailed Description

The principles and features of this invention are described below in conjunction with embodiments, which are included to explain the invention and not to limit the scope of the invention. The present invention will be described in detail below with reference to examples.

The palladium ion probe related to the embodiment of the invention has a structural formula shown as the following formula 1:

example 1: preparation of Compound 1

This example was also prepared in a one-step process according to the following route:

the specific process comprises the following steps: cy7-Cl, bis (2-methylpyridine) amine and triethylamine were mixed in a molar ratio of 1: 1:1, adding 1mmol of the mixture into 10ml of the mixture, reacting in an organic solvent DMF for 4 hours at 40 ℃, wherein the color of the solution changes from green to blue during the reaction, after the reaction system is cooled to room temperature, extracting by using dichloromethane and water in a volume ratio of 1:10, extracting by using 20ml of dichloromethane and 200ml of water, after extraction and delamination, drying the dichloromethane layer by using 1g of anhydrous magnesium sulfate, and removing the solvent by rotary evaporation after drying to obtain about 0.4g of blue product, namely the compound 1.

Example 2: identification of Compound 1

The blue compound 1 prepared in example 1 was subjected to nuclear magnetic analysis with a nuclear magnetic model of Bruker AVANCE 400, at room temperature, and with nuclear magnetic resonance data of:

1H NMR(400MHz,CDCl3)δ8.72(d,J＝4.5Hz,2H),7.85(t,J＝6.5Hz,2H),7.67(d,J＝13.5Hz,2H),7.40(dd,J＝7.1,5.2Hz,2H),7.32(m,J＝7.5Hz,6H),7.15(t,J＝7.4Hz,2H),7.00(d,J＝7.9Hz,2H),5.90(d,J＝13.6Hz,2H),4.74(s,4H),4.01(q,J＝7.1Hz,4H),2.60(t,J＝6.4Hz,4H),1.94(dd,J＝12.7,6.5Hz,2H),1.45(s,12H),1.38(t,J＝7.2Hz,6H).13C NMR(101MHz,CDCl3)δ173.41,169.06,156.29,149.72,143.67,142.14,140.47,138.19,128.56,124.66,124.28,123.66,123.43,122.19,109.39,96.90,59.97,48.26,38.78,29.69,28.62,25.07,21.95,11.90.

a quality and simplicity analysis was performed on the blue compound 1 prepared in example 1, the model of the mass spectrometer was an Orbitrap Fusion mass spectrometer, the test conditions were room temperature, and the high resolution mass spectrometry result of the blue compound 1 was: HRMS m/z calculated for C₄₆H₅₂N₅+:[(M+H)+]674.4217,found674.4223。

Example 3: compound 1 p Pd²⁺Selectivity of (2).

To a 25. mu.M solution of Compound 1 in 0.5% pure dimethyl sulfoxide (DMSO) was added 1.0 equivalent of each of different metal cations (Pd)²⁺，Ca²⁺,Cd²⁺,Co²⁺,Cr²⁺,Cs⁺,Cu²⁺,Fe²⁺,Fe³⁺,Ir³⁺,Mg²⁺,Mn²⁺,Ni²⁺,Pb²⁺,Pt²⁺,Re⁺,Rh³⁺,Zn²⁺). As can be seen from FIG. 1, when 1.0 equivalent of Pd was added to the compound 1 solution²⁺After that, the absorption of compound 1 at 710nm completely disappears, and a new absorption peak appears at 770nm, while other metal ions have little influence on the absorption of compound 1.

Meanwhile, the solution color visually changed to: when adding Pd²⁺After that, the solution changes from blue to green, and when other metal ions are added, the color of the solution is almost unchanged.

Second, the effect of metal ions on solution fluorescence was tested. To a solution of Compound 1 (25. mu.M) was added 1.0 equivalent of Pd²⁺The fluorescence of the solution at 770nm decreased while the fluorescence at 800nm increased. The fluorescence of the solution is substantially unchanged when other metal ions are added. From F/F0 (FIG. 2) at 770nm, where F is the fluorescence value of Compound 1 and F0 is the fluorescence value after addition of different metal ions, it can be seen that Compound 1 can selectively recognize Pd²⁺。

Example 4: compound 1 p Pd²⁺Ultraviolet-visible titration experiment of

To a 25. mu.M solution of Compound 1, 0.5% pure dimethyl sulfoxide (DMSO) was added Pd at various concentrations²⁺As shown in FIG. 3, with Pd²⁺With increasing concentration (0-8 μ M), the uv-vis absorption of the solution at λ 710nm gradually decreased, the absorption peak gradually red shifted, and the uv-vis absorption at λ 770nm gradually increased. And the UV-visible absorption intensities at λ 710nm and λ 770nm are both comparable to Pd²⁺In the range of 0 to 0.28 equivalentWith a good linear relationship (figure 4). Calculating the Pd as the probe pair according to a calculation formula DL of detection limit DL (detection limit) of 3s/k (s is a standard deviation of a blank sample, and k is a slope) according to the rules of International Union of Pure and Applied Chemistry (IUPAC) by a fitted linear equation²⁺The detection limit of (3) was 39.29 nM. Shows that the probe compound 1 has high sensitivity and can be used for Pd²⁺Trace detection of (2).

Example 5: compound 1 p Pd²⁺Fluorescence titration experiment of

To a 25. mu.M solution of Compound 1, different concentrations of Pd were added in 0.5% DMSO purified water²⁺As shown in fig. 5 and 6, with Pd²⁺The increase in concentration (0-60 μ M) gradually decreased the fluorescence intensity at λ 770nm and increased the fluorescence intensity at λ 800nm for the solution. It is shown that the compound 1 can identify palladium ions and combine with the palladium ions to change the change of the fluorescence absorption wavelength of the solution.

Example 6: compound 1 p Pd in rat body²⁺Photoacoustic imaging experiment

Before and after the injection of the compound 1 solution into the mice, the ultraviolet acousto-optic imaging comparison test is carried out, and the strong photoacoustic signal is observed at 770nm and almost no photoacoustic signal is observed at 860nm after the injection of the compound 1. When adding Pd²⁺The photoacoustic signal at 770nm then disappeared, and a strong photoacoustic signal appeared at 860nm (FIG. 6). Simultaneous photoacoustic signal at 860nm with Pd²⁺There is a good linear relationship of the concentration of (2) (FIG. 7). Description of Compound 1 solution vs Pd²⁺The selectivity and the corresponding change characteristic of ultraviolet light can be used for Pd in organisms²⁺In qualitative and quantitative detection.

The specific structure of the compound 1 prepared by the present invention can be specifically illustrated by the above examples, and the compound 1 can react with Pd²⁺Has high selectivity and sensitivity, can selectively identify palladium ions, and is not interfered by other metal ions. With the addition of palladium ions, the blue color of the compound 1 solution is changed into green color, the fluorescence of the solution at 770nm is gradually weakened, the fluorescence at 800nm is gradually enhanced, the absorption at 710nm is continuously reduced, and the absorption at 770nm is gradually reducedThe yield is increasing. Meanwhile, the photoacoustic signal at 770nm is gradually weakened, and the photoacoustic signal at 860nm is gradually strengthened. Therefore, the compound 1 can be used as a novel photoacoustic ratio type palladium ion probe for qualitatively and quantitatively determining Pd in a solution sample or a living body²⁺The content of (c).

It will be understood by those skilled in the art that the present invention is not limited to the embodiments described above, which are described in the specification and illustrated only to illustrate the principle of the present invention, but that various changes and modifications may be made therein without departing from the spirit and scope of the present invention, which fall within the scope of the invention as claimed. The scope of the invention is defined by the appended claims and equivalents thereof.