A Functionalized Upconversion Nanoprobe with Strong Anti-Interference Ability and High Sensitivity for Perchlorate Detection

Abstract

The present invention provides a functionalized upconversion nanoprobe with strong anti-interference ability and high sensitivity for detecting perchlorate. The functionalized upconversion nanoprobe is composed of NaYF4:Yb@NaYF4:Yb / Er with a core-shell structure as the matrix and rhodamine thiourea derivative as the functionalized ligand. The functionalized upconversion nanoprobe provided by the present invention has the function of highly sensitive detection of perchlorate. Under the irradiation of 980 nm light, the upconversion luminescence gradually changes from green to red. Through the position of the CIE coordinates, the functionalized upconversion nanoprobe has the ability of semi-quantitative detection of perchlorate. The functionalized upconversion nanoprobe has extremely strong anti-interference ability and excellent detection limit. The detection process does not require complex analytical equipment, realizing rapid trace detection of perchlorate. At the same time, it makes up for the influence of background interference when detecting perchlorate in a complex environment. Therefore, the development of the functionalized upconversion nanoprobe can provide effective technical support for the field of trace detection of improvised explosives in the actual environment.

Description

Technical Field

[0001] The present invention belongs to the field of analytical detection, and provides a functionalized upconversion nanoprobe for highly anti-interference and highly sensitive detection of perchlorate. Background Art

[0002] Perchlorate, as the main raw material for preparing improvised explosives, has good water solubility and chemical stability, and is extremely easy to cause persistent pollution to water and soil environments. After entering the human body, it accumulates in the body, endangers thyroid function, inhibits hormone production, and affects the growth and development of fetuses and children. Therefore, it is of great practical significance to perform on-site ultrasensitive, rapid, specific and accurate identification and detection of perchlorate.

[0003] Currently, due to the special significance of perchlorate detection, scholars at home and abroad have carried out a large number of studies. The main detection methods of perchlorate include: ion chromatography, liquid chromatography-mass spectrometry, electrochemistry, surface-enhanced Raman spectroscopy, and photochemistry. Among them, fluorescence detection technology has received extensive attention due to its high sensitivity, fast reaction speed, strong specificity, visualization of detection signals, and simple operation. So far, researchers have explored a large number of organic small molecule fluorescent probes for detecting perchloric acid. The rhodamine-based organic probe designed and synthesized by the Das team achieved a colorimetric-fluorescent dual-mode response to perchlorate (RSC Advances, 2013, 3(33): 14044.). The probe was colorless and fluorescent in an acetonitrile / water (8:2, v / v) solution. When perchlorate was added, an emission peak appeared at 569 nm in the fluorescence spectrum of the probe solution, and this emission peak increased with the increase in perchlorate concentration. Under ultraviolet light irradiation, bright orange fluorescence was emitted. At the same time, a new absorption peak appeared at 541 nm in its absorption spectrum, and it increased with the increase in perchlorate concentration. Under daylight, it was found that the color changed from colorless to pink, and the detection limit was 1×10 -7M. The detection mechanism mainly causes the spirolactam hydrazide to open the ring by the perchlorate ion forming a hydrogen bond with the probe, enabling the probe to form a conjugated structure and release the rhodamine fluorophore, thereby simultaneously causing dual responses of color and fluorescence. The Kumar team explored a chemical sensor based on a perylene diimide-based probe (Chemical Communications, 2014, 50(90): 13994-13997). The probe can form a 1:1 complex with the perchlorate ion in HEPES buffer (pH = 7.4) and produce fluorescence quenching. By forming C-H…O hydrogen bond interactions between the benzimidazole group at one end and the benzene ring at the other end in the probe structure, the perchlorate ion is embedded in the cavity, resulting in a change in the molecular configuration to achieve the purpose of detection. However, as single fluorescence probes, it is difficult for both of them to achieve the purpose of detection when encountering strong background fluorescence interference, and at the same time, there is a bottleneck in the improvement of sensitivity. Therefore, the directional design of highly anti-interference detection based on organic small molecule fluorescence probes is of great significance for achieving ultra-precise visualization detection.

[0004] To solve this problem. In contrast, rare earth-doped upconversion nanomaterials can convert low-energy near-infrared light into high-energy ultraviolet or visible light. Due to their unique upconversion luminescence mechanism, they have significant advantages such as high photochemical stability, low autofluorescence signal, excellent signal-to-noise ratio, and wide emission range, which can effectively avoid background interference in complex environments. For example, the research group of Professor Lu Ge-Yu at Jilin University designed the binding of the surface of rare earth nanoparticles with ligands to achieve the detection of glutathione (SENSORS AND ACTUATORS B-CHEMICAL 2022, 369). However, limited by the energy resonance efficiency, the detection limit is 140 μM. Therefore, how to design upconversion nanoprobes with high sensitivity and high anti-interference is a major and valuable challenge. Summary of the Invention

[0005] The object of the present invention is to provide a functionalized upconversion nanoprobe for strongly anti-interference and highly sensitive detection of perchlorate. The probe is composed of a core-shell structured NaYF 4 :Yb@NaYF 4: It consists of Yb / Er and rhodamine thiourea derivatives. The core innovation lies in precisely regulating the energy level matching between the probe as a ligand and the upconversion nanoparticles. By turning off and on the Förster resonance energy transfer effect before and after the addition of the analyte perchlorate, the significant change in the upconversion optical signal is thus controlled. Specifically, for the detection of perchlorate by the functionalized upconversion nanoprobe described in the present invention, the Stokes shift change of the probe absorption spectrum before and after the addition of the analyte is utilized, thereby generating a large area of spectral overlap. Under the irradiation of a 980-nm laser: the green upconversion emission turns into red upconversion emission within 3 s. The functionalized upconversion nanoprobe in the present invention has extremely strong anti-interference ability and excellent detection limit. The detection process does not require complex analytical equipment, realizing the rapid trace detection of perchlorate. At the same time, it makes up for the influence of background interference when detecting perchlorate in a complex environment. Therefore, the development of this functionalized upconversion nanoprobe can provide effective technical support for the field of trace detection of improvised explosives in the actual environment.

[0006] A functionalized upconversion nanoprobe for strongly anti-interfering and highly sensitive detection of perchlorate according to the present invention, the probe uses a core-shell structured NaYF 4 :Yb@NaYF 4 :Yb / Er rare earth upconversion nanoparticles as the matrix material, and a small molecule fluorescent probe as the functionalized ligand on the surface, wherein:

[0007] The core-shell structured rare earth upconversion nanoparticles are: NaYF 4 :Yb 20%@NaYF 4 :Yb 17% / Er 3%;

[0008] The functionalized ligand is: rhodamine thiourea derivative 1-(2-(3',6'-bis(diethylamino)-3-oxospiro[isoindoline-1,9'-xanthene]-2-yl)ethyl)thiourea;

[0009] Solvent: 50% ethanol aqueous solution;

[0010] The specific operation is carried out according to the following steps:

[0011] The core-shell structured NaYF 4 :Yb@NaYF 4 :Yb / Er was synthesized by the co-precipitation method of epitaxial growth:

[0012] a. Under nitrogen protection, sodium fluoride and a mixture of oleic acid / octadecene were added, heated to 110 °C and stirred for 1 hour, then heated to 320 °C and reacted for 75 minutes. Subsequently, YCl was added in a molar ratio of 80:20 3 and YbCl 3Add it to an equimolar mixed solvent of oleic acid / octadecene and react for 20 minutes; then, according to a molar ratio of 80:17:3, add YCl 3 , YbCl 3 and ErCl 3 to the equimolar mixed solvent of oleic acid / octadecene, continue to react for 20 minutes, then stop heating, and after centrifugal purification with a mixed solution of cyclohexane and ethanol with a volume ratio of 1:5, the core-shell structured rare-earth upconversion nanoparticles are obtained: NaYF 4 :Yb@NaYF 4 :Yb / Er;

[0013] b. Reflux a mixture of 1.0 g of N-(rhodamine-B) lactam ethylenediamine and 0.99 g of potassium thiocyanate in an ethanol / 2M HCl aqueous solution with a volume ratio of 4:1 for 10 hours to obtain a crude solid. Then, perform silica gel chromatography with 200 - 300 mesh silica gel and elute with an eluent of ethyl acetate:petroleum ether with a volume ratio of 2:1 to obtain the required light purple solid product, and recrystallize with acetonitrile to obtain the pure probe;

[0014] c. Ultrasonically oscillate the core-shell structured upconversion nanoparticles obtained in step a in a 0.1 mol / L hydrochloric acid solution for 20 min, then immediately wash with an aqueous ethanol solution with a concentration of 50% until neutral. Then, soak the bare upconversion nanoparticles and the probe with a mass ratio of 1:5 - 10 in an ethanol solution, ultrasonically treat for 20 min and then reflux and stir for 48 h. Utilize the coordination of the amino group at the end of the probe with the rare-earth ions Y, Yb, and Er to modify the probe onto the surface of the core-shell structured rare-earth upconversion nanoparticles, and thus obtain: rhodamine thiourea derivative-functionalized NaYF 4 :Yb@NaYF 4 :Yb / Er upconversion nanoprobe.

[0015] The functionalized upconversion nanoprobe for strongly anti-interfering and highly sensitive detection of perchlorate has a response time of 3 s for detecting perchlorate, the upconversion emission gradually changes from green to red, and the detection limit is 0.17 nM.

[0016] The functionalized upconversion nanoprobe for strongly anti-interfering and highly sensitive detection of perchlorate resists 17 common interfering ions F - , I - , Br - , Cl - , BrO 4 - , IO 3 - , NO 3 - , NO 2 - , SO 4- , HPO 4 2- , PO 4 3- , SCN - , ClO - , ClO 2 - , CH 3 COO - , CO 3 2- , HCO 3 - and the interference of various background fluorescent substances.

[0017] Detect perchlorate with the obtained functionalized upconversion nanoprobes:

[0018] Dissolve the obtained high-performance functionalized upconversion nanoprobes in an ethanol solution, place them in a quartz cuvette, add perchlorate, and within 3 s, under 980 nm infrared excitation, the fluorescence changes from green to red. When the perchlorate concentration is from 0 μM / L to 60 μm / L, the emission intensity at 550 nm has a linear relationship with the perchlorate concentration, and the detection limit is 0.17 nM.

[0019] Compared with the prior art, the beneficial effects of the present invention are:

[0020] 1. The functionalized upconversion nanoprobes described in the present invention can achieve strong anti-interference detection of perchlorate in a complex environment;

[0021] 2. The functionalized upconversion nanoprobes described in the present invention have the ability to semi-quantitatively detect perchlorate, and achieve semi-quantitative sensing of the perchlorate concentration through the positioning change in the CIE coordinates;

[0022] 3. In the functionalized upconversion nanoprobes described in the present invention, the rare earth nanoparticles as energy donors are ingeniously designed in structure, and through the reasonable distribution of the sensitizer Yb and the activator Er, high-efficiency Förster energy resonance transfer is achieved, improving the detection sensitivity.

[0023] 4. The functionalized upconversion nanoprobes described in the present invention can detect perchlorate without complex analysis equipment and can be directly identified by the naked eye;

[0024] 5. The functionalized upconversion nanoprobes described in the present invention do not require any pretreatment of the analyte, are simple to operate, convenient for popularization and application, and can completely achieve the purpose of detecting perchlorate at low cost. Description of the Drawings

[0025] Figure 1 It is the emission spectrum of the present invention under a 980 nm laser;

[0026] Figure 2 This is the detection effect diagram of the present invention. Among them, (A) is the emission spectrum diagram of the functionalized upconversion nanoprobe obtained by adding perchlorate with a concentration of 0 - 60 μM in ethanol solvent; (B) is the linear equation obtained by fitting with the concentration of perchlorate as the abscissa and the ratio of the upconversion emission peak intensity at 550 nm to the upconversion emission peak intensity at 650 nm as the ordinate; (C) is the CIE coordinate schematic diagram of the light emitted by the functionalized upconversion nanoprobe under 980 nm laser irradiation after adding different concentrations of perchlorate, which is used for semi - quantitative detection.

[0027] Figure 3 This is the test of the anti - interference and selectivity of the functionalized upconversion nanoprobe of the present invention. The upconversion luminescence photos were taken by a digital camera, including 17 common cation and anion interferents: F - , I - , Br - , Cl - , BrO 4 - , IO 3 - , NO 3 - , NO 2 - , SO 4 , HPO 4 2- , PO 4 3- , SCN - , ClO - , ClO 2 - , CH 3 COO - , CO 3 2- , HCO 3 - ;

[0028] Figure 4 In the presence of three common fluorescent substances (coumarin, hydroxyfluorescein, cyanine) interference, the present invention can still efficiently and accurately detect perchlorate. Detailed implementation mode

[0029] The following further illustrates the present invention through specific embodiments, but the invention is not limited to these embodiments.

[0030] Example 1

[0031] The core - shell structure rare - earth upconversion nanoparticles are: NaYF 4 :Yb 20%@NaYF 4 :Yb 17% / Er 3%;

[0032] The functional ligand is: rhodamine thiourea derivative 1-(2-(3',6'-bis(diethylamino)-3-oxospiro[isoindoline-1,9'-xanthene]-2-yl)ethyl)thiourea;

[0033] Solvent: 50% ethanol aqueous solution;

[0034] The core-shell structured NaYF was synthesized by the co-precipitation method of epitaxial growth 4 :Yb@NaYF 4 :Yb / Er:

[0035] a. Under nitrogen protection, sodium fluoride and oleic acid / octadecene mixture were added, the temperature was raised to 110 °C and stirred for 1 hour, then heated to 320 °C and reacted for 75 minutes. Subsequently, YCl was added in a molar ratio of 80:20 3 and YbCl 3 were added to the equimolar mixed solvent of oleic acid / octadecene, and the reaction was carried out for 20 minutes; then YCl was added in a molar ratio of 80:17:3 3 、YbCl 3 and ErCl 3 were added to the equimolar mixed solvent of oleic acid / octadecene, and the reaction was continued for 20 minutes. Then the heating was stopped, and after centrifugal purification with a mixed solution of cyclohexane and ethanol with a volume ratio of 1:5, the core-shell structured rare-earth upconversion nanoparticles were obtained: NaYF 4 :Yb@NaYF 4 :Yb / Er;

[0036] b. A mixture of 1.0 g of N-(rhodamine-B) lactam ethylenediamine and 0.99 g of potassium thiocyanate was refluxed in an ethanol / 2M HCl aqueous solution with a volume ratio of 4:1 for 10 hours to obtain a crude solid. Then, it was chromatographed on 200-mesh silica gel and eluted with an eluent of ethyl acetate:petroleum ether with a volume ratio of 2:1 to obtain the required light purple solid product. After recrystallization with acetonitrile, the pure probe was obtained;

[0037] c. The core-shell structured upconversion nanoparticles obtained in step a were ultrasonically oscillated in 0.1 mol / L hydrochloric acid solution for 20 min, then immediately washed with 50% ethanol aqueous solution until neutral. Then, the bare upconversion nanoparticles and the probe with a mass ratio of 1:5 were immersed in ethanol solution, ultrasonically treated for 20 min and then refluxed and stirred for 48 h. By using the coordination effect of the amino group at the end of the probe with rare-earth ions Y, Yb, and Er, the probe was modified onto the surface of the core-shell structured rare-earth upconversion nanoparticles, and thus the rhodamine thiourea derivative-functionalized NaYF 4 :Yb@NaYF 4 :Yb / Er upconversion nanoprobe was obtained.

[0038] Detection of perchlorate using the functionalized upconversion nanoprobes obtained in Example 1:

[0039] Dissolve the obtained high-performance functionalized upconversion nanoprobes in an ethanol solution, place them in a quartz cuvette, and add explosives suspected of containing perchlorate. If perchlorate is present, within 3 s, under 980 nm infrared excitation, the upconversion emission changes from green to red. When the perchlorate concentration is 0 μM - 60 μM, the detection limit is 0.17 nM. If perchlorate is not present, the green luminescence remains unchanged.

[0040] Example 2

[0041] The core-shell structured rare-earth upconversion nanoparticles are: NaYF 4 :Yb 20%@NaYF 4 :Yb 17% / Er 3%;

[0042] The functionalized ligand is: rhodamine thiourea derivative 1-(2-(3',6'-bis(diethylamino)-3-oxospiro[isoindoline-1,9'-xanthene]-2-yl)ethyl)thiourea;

[0043] Solvent: 50% ethanol aqueous solution;

[0044] The core-shell structured NaYF was synthesized by the co-precipitation method of epitaxial growth 4 :Yb@NaYF 4 :Yb / Er:

[0045] a. Under nitrogen protection, add sodium fluoride and an oleic acid / octadecene mixture, heat to 110 °C and stir for 1 hour, then heat to 320 °C and react for 75 minutes. Subsequently, add YCl 3 and YbCl 3 to an equimolar mixed solvent of oleic acid / octadecene, and react for 20 minutes; then add YCl 3 、YbCl 3 and ErCl 3 to an equimolar mixed solvent of oleic acid / octadecene, and continue to react for 20 minutes. Then stop heating, and after centrifugal purification with a 1:5 volume ratio mixture of cyclohexane and ethanol, the core-shell structured rare-earth upconversion nanoparticles: NaYF 4 :Yb@NaYF 4 :Yb / Er;

[0046] b. A mixture of 1.0 g of N-(rhodamine-B) lactam ethylenediamine and 0.99 g of potassium thiocyanate was refluxed in an ethanol / 2M HCl aqueous solution with a volume ratio of 4:1 for 10 hours to obtain a crude solid. Then, it was subjected to silica gel chromatography with 300 meshes, and eluted with an eluent of ethyl acetate:petroleum ether with a volume ratio of 2:1 to obtain the desired light purple solid product. The product was recrystallized with acetonitrile to obtain a pure probe.

[0047] c. The core-shell structured upconversion nanoparticles obtained in step a were ultrasonically oscillated in a 0.1 mol / L hydrochloric acid solution for 20 min, and then immediately washed with an ethanol aqueous solution with a concentration of 50% until neutral. Then, the bare upconversion nanoparticles and the probe with a mass ratio of 1:8 were immersed in an ethanol solution. After 20 min of ultrasonication, they were refluxed and stirred for 48 h. By using the coordination effect of the amino group at the end of the probe with rare earth ions Y, Yb, and Er, the probe was modified onto the surface of the core-shell structured rare earth upconversion nanoparticles, thus obtaining: rhodamine thiourea derivative functionalized NaYF 4 :Yb@NaYF 4 :Yb / Er upconversion nanoprobe.

[0048] The functionalized upconversion nanoprobe obtained in Example 2 was used to detect perchlorate:

[0049] The prepared high-performance functionalized upconversion nanoprobe was dissolved in an ethanol solution and placed in a quartz cuvette. Subsequently, the interfering ions commonly found in perchlorate detection were added: F - ,I - ,Br - ,Cl - ,BrO 4 - ,IO 3 - ,NO 3 - ,NO 2 - ,SO 4 - ,HPO 4 2- ,PO 4 3- ,SCN - ,ClO - ,ClO 2 - ,CH 3 COO - ,CO 3 2- ,HCO 3 - , it was found that the green upconversion emission remained unchanged. Then, perchlorate was added. Within 3 s, it could be found that the upconversion emission changed from green to red. Subsequently, perchlorate and F- , I - , Br - , Cl - , BrO 4 - , IO 3 - , NO 3 - , NO 2 - , SO 4 - , HPO 4 2- , PO 4 3- , SCN - , ClO - , ClO 2 - , CH 3 COO - , CO 3 2- , HCO 3 - Mixing with interfering ions will still not affect the detection results, demonstrating the superiority of the detection performance.

[0050] Example 3

[0051] The core-shell structured rare-earth upconversion nanoparticles are: NaYF 4 :Yb 20%@NaYF 4 :Yb 17% / Er 3%;

[0052] The functional ligand is: rhodamine thiourea derivative 1-(2-(3',6'-bis(diethylamino)-3-oxospiro[isoindoline-1,9'-xanthene]-2-yl)ethyl)thiourea;

[0053] The solvent: 50% ethanol aqueous solution;

[0054] Synthesized the core-shell structured NaYF by the co-precipitation method of epitaxial growth 4 :Yb@NaYF 4 :Yb / Er:

[0055] a. Under nitrogen protection, add sodium fluoride and oleic acid / octadecene mixture, heat to 110 °C and stir for 1 hour, then heat to 320 °C and react for 75 minutes. Subsequently, add YCl 3 and YbCl 3 to the equimolar mixed solvent of oleic acid / octadecene, and react for 20 minutes; then add YCl 3 , YbCl 3and ErCl 3 It was added to an equimolar mixed solvent of oleic acid / octadecene, and the reaction was continued for 20 minutes. Then, the heating was stopped. After centrifugal purification with a mixed solution of cyclohexane and ethanol with a volume ratio of 1:5, rare earth upconversion nanoparticles with a core-shell structure were obtained: NaYF 4 :Yb@NaYF 4 :Yb / Er;

[0056] b. A mixture of 1.0 g of N-(rhodamine-B) lactam ethylenediamine and 0.99 g of potassium thiocyanate was refluxed in an ethanol / 2M HCl aqueous solution with a volume ratio of 4:1 for 10 hours to obtain a crude solid. Then, it was subjected to silica gel chromatography with a 250-mesh sieve, and eluted with an eluent of ethyl acetate:petroleum ether with a volume ratio of 2:1 to obtain the required light purple solid product. The product was recrystallized with acetonitrile to obtain a pure probe;

[0057] c. The core-shell structured upconversion nanoparticles obtained in step a were ultrasonically oscillated in a 0.1 mol / L hydrochloric acid solution for 20 min, and then immediately washed with an ethanol aqueous solution with a concentration of 50% until neutral. Then, the bare upconversion nanoparticles and the probe with a mass ratio of 1:10 were immersed in an ethanol solution, and after 20 min of ultrasonic treatment, they were refluxed and stirred for 48 h. By using the coordination effect of the amino group at the end of the probe with rare earth ions Y, Yb, and Er, the probe was modified onto the surface of the core-shell structured rare earth upconversion nanoparticles, and thus the obtained product was: rhodamine thiourea derivative-functionalized NaYF 4 :Yb@NaYF 4 :Yb / Er upconversion nanoprobe.

[0058] The functionalized upconversion nanoprobe obtained in Example 3 was used to detect perchlorate:

[0059] 20 μL of the functionalized upconversion nanoprobe ethanol solution was respectively measured and dropped onto the substrates of blank hydrogel, hydrogel with blue fluorescent dye, hydrogel with yellow-green dye, and hydrogel with red pigment dye. Then, they were respectively exposed to dust containing trace perchlorate particles. After standing for a period of time, they were irradiated with a 980-nm laser, and the change of upconversion luminescence from green to red could still be clearly observed.

[0060] Although the above embodiments describe the present invention, it should be understood that on the premise of not violating the spirit of the present invention, the matrix materials loaded with the functionalized upconversion nanoprobes can be exchanged, and it is equally applicable to the test of perchlorate in other fields, and these changes also belong to the scope of the present invention.

Claims

1. A functionalized upconversion nanoprobe for detecting perchlorate, characterized in that The probe uses a core-shell structured NaYF 4 :Yb @NaYF 4 :Yb / Er rare-earth upconversion nanoparticles as the matrix material, and a small molecule fluorescent probe as the surface functionalized ligand, where: The core-shell structured rare-earth upconversion nanoparticles are: NaYF 4 : 20% Yb@NaYF 4 : 17% Yb / 3% Er; the functionalized ligand is: rhodamine thiourea derivative 1-(2-(3',6'-bis(diethylamino)-3-oxospiro[isoindoline-1,9'-xanthene]-2-yl)ethyl)thiourea; the solvent: an ethanol aqueous solution with a concentration of 50%; the specific operation is carried out according to the following steps: The core-shell structured NaYF was synthesized by co-precipitation method using epitaxial growth 4 :Yb@NaYF 4 :Yb / Er: a. Under nitrogen protection, sodium fluoride and an oleic acid / octadecene mixture are added, the temperature is raised to 110 °C and stirred for 1 hour, then heated to 320 °C and reacted for 75 minutes. Subsequently, YCl is added in a molar ratio of 80:20 3 and YbCl 3 to an equimolar mixed solvent of oleic acid / octadecene and reacted for 20 minutes; then YCl in a molar ratio of 80:17:3 3 、YbCl 3 and ErCl 3 are added to an equimolar mixed solvent of oleic acid / octadecene and the reaction is continued for 20 minutes. Then the heating is stopped, and after centrifugal purification with a cyclohexane / ethanol mixture with a volume ratio of 1:5, core-shell structured rare earth upconversion nanoparticles: NaYF 4 :Yb@NaYF 4 :Yb / Er are obtained; b. A mixture of 1.0 g of N-(rhodamine-B) lactam ethylenediamine and 0.99 g of potassium thiocyanate is refluxed in an ethanol / 2 M HCl aqueous solution with a volume ratio of 4:1 for 10 hours to obtain a crude solid, and then chromatographed on silica gel with 200-300 mesh, eluted with an eluent of ethyl acetate: petroleum ether with a volume ratio of 2:1 to obtain the required light purple solid product, and then recrystallized with acetonitrile to obtain a pure probe; c. Ultrasonically oscillate the core-shell structured upconversion nanoparticles obtained in step a in a 0.1 mol / L hydrochloric acid solution for 20 min, then immediately wash with an aqueous ethanol solution with a concentration of 50% until neutral. Next, soak the bare upconversion nanoparticles and the probe with a mass ratio of 1:5 - 10 in an ethanol solution, ultrasonically treat for 20 min and then reflux and stir for 48 h. Utilize the coordination effect of the amino group at the end of the probe with the rare earth ions Y, Yb, and Er to modify the probe onto the surface of the core-shell structured rare earth upconversion nanoparticles, thus obtaining: rhodamine thiourea derivative-functionalized NaYF 4 :Yb @NaYF 4 :Yb / Er upconversion nanoprobe.

2. A detection method for the functionalized upconversion nanoprobe for detecting perchlorate as described in claim 1, characterized in that the response time for detecting perchlorate is 3 s, the upconversion emission gradually changes from green to red, and the detection limit is 0.17 nM.

3. A detection method for the functionalized upconversion nanoprobe for detecting perchlorate as described in claim 1, characterized in that Resistance to interference from 17 common interfering ions in the detection of perchlorate F - , I - , Br - ,Cl - ,BrO 4 - ,IO 3 - ,NO 3 - ,NO 2 - ,SO 4 - ,HPO 4 2- ,PO 4 3- ,SCN - ,ClO - ,ClO 2 - ,CH 3 COO - ,CO 3 2- ,HCO 3 - interference

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