Iridium and chromium co-doped long afterglow nano material as well as preparation method and application thereof

Abstract

The invention belongs to the technical field of biomedicine, and particularly relates to an iridium and chromium co-doped long afterglow nano material as well as a preparation method and application thereof. The iridium and chromium co-doped zinc gallium germanate long-afterglow nano-material is a iridium and chromium co-doped zinc gallium germanate long-afterglow nano-material, the molecular formula of the iridium and chromium co-doped zinc gallium germanate long-afterglow nano-material is Zn1. 3Ga1. 6Ge0. 1O4: Cr 0.0075, and Ir 0.05, and the invention provides a preparation method of the iridium and chromium co-doped zinc gallium germanate long-afterglow nano-material. The iridium and chromium co-doped long afterglow nano material has afterglow imaging capability, peroxidase-like activity and photothermal conversion potential, can realize cell imaging and photothermal imaging of tumors after being used, and has the potential of realizing tumor treatment. In addition, in the electro-catalytic reaction, the iridium and chromium co-doped long afterglow nano material improves the oxygen evolution reaction of the electrode under the light irradiation condition.

Description

Technical Field

[0001] The invention belongs to the field of biomedical technology, and specifically relates to an iridium and chromium co-doped long afterglow nano material and a preparation method and application thereof. Background Art

[0002] Chromium-doped long afterglow nanomaterials (PLNPs) can still emit light for a long time after the excitation light stops, so they can effectively avoid the spontaneous light emission of biological tissues or background interference and achieve high signal-to-noise ratio imaging. When the afterglow weakens, it can be re-excited with white light or red LED lights, which prolongs the afterglow imaging time and further broadens its application range. By regulating the composition of the material and modifying its surface, near-infrared long afterglow nanomaterials can be given multifunctionality and applied to the fields of medical imaging, disease diagnosis and treatment, and electrocatalysis.

[0003] In recent years, two types of nanozymes based on PLNPs have been developed. The first type is surface chemically modified PLNPs, which introduces specific functional groups on the surface of PLNPs to change its surface properties. Its disadvantages are: 1) shielding targeting molecules: specific functional groups will shield or destroy the targeting molecules that have been grafted on the surface of PLNPs, thereby affecting the targeting ability of PLNPs; 2) non-specific binding: too many non-specific functional groups will cause PLNPs to bind non-specifically to non-target cells or tissues, reducing the efficiency of targeted delivery. The second type is coated PLNPs, which uses PLNPs as the core and coats the PLNPs with a shell layer to protect the active ingredients inside, and reintroduces targeting molecules through the functional groups on the shell layer to restore surface accessibility; its disadvantages are: 1) increase in hydrodynamic diameter: the addition of the shell layer will increase the overall size of the particles, affecting the distribution, targeting ability and clearance rate of PLNPs in the body; 2) decreased targeting efficiency: the increase in size will reduce the ability of PLNPs to penetrate biological membranes, thereby affecting its binding efficiency with target cells, and then affecting the application of PLNPs in vivo. Summary of the invention

[0004] The purpose of the present invention is to provide an iridium and chromium co-doped long afterglow nanomaterial and a preparation method and application thereof. The present invention incorporates iridium and chromium metals into zinc gallium germanate long afterglow nanomaterials by co-doping to obtain iridium and chromium co-doped long afterglow nanomaterials, namely Ir(IV)-PLNPs. The obtained Ir(IV)-PLNPs overcome the technical defects caused by surface chemically modified PLNPs and coated PLNPs in the prior art, and the obtained Ir(IV)-PLNPs have afterglow imaging capability, peroxidase-like activity and photothermal conversion potential. After use, imaging of cells and photothermal imaging of tumors can be achieved, and the potential for tumor treatment can be achieved. In addition, in the electrocatalytic reaction, Ir(IV)-PLNPs enhance the oxygen evolution reaction of the electrode under light irradiation, and can be used as an electrocatalytic material.

[0005] The present invention is implemented by the following technical solutions:

[0006] An iridium and chromium co-doped long afterglow nanomaterial, the molecular formula of which is Zn 1.3 Ga 1.6 Ge 0.1 O4:Cr 0.0075 ,Ir 0.05 The Ir doping amount of 5% in the molecular formula provided in this application is obtained by experiments in this application. Different iridium doping amounts have different performances. In practical applications, the Ir doping amount can be adjusted according to performance requirements.

[0007] Preferably, the iridium and chromium co-doped long afterglow nanomaterial is an iridium and chromium co-doped zinc gallium germanate long afterglow nanomaterial, and iridium is doped into the chromium-doped zinc gallium germanate long afterglow nanomaterial.

[0008] Preferably, the particle size of the iridium and chromium co-doped long afterglow nanomaterial is 10.2±2.3 nm, and this data is obtained based on the SEM image.

[0009] The present invention also protects a preparation method of iridium and chromium co-doped long afterglow nanomaterials, the preparation method is a co-doping method, comprising the following steps:

[0010] Zn 2+ , Ga 3+ ,Ge 4+ ,Cr 3+ and Ir 4+ The ionic solutions are mixed in water to form a homogeneous aqueous solution;

[0011] Zn 2+ From zinc nitrate hexahydrate, Ga 3+ Derived from gallium nitrate solution, which is obtained by dissolving gallium oxide in 38% dilute nitric acid solution. 4+ Derived from germanium oxide dissolved in 3% ammonia water, Cr 3+From chromium nitrate nonahydrate, Ir 4+ Derived from iridium chloride hydrate; gallium nitrate solution and germanium oxide dissolved in 3% ammonia water are both intended to form ionic solutions;

[0012] After adjusting the aqueous solution to a pH of 8.0-10.0 with ammonia water, a precursor solution is obtained; ammonia water is added dropwise to precipitate metal cations with ammonia water to form a white precipitate, and the growth of crystals is controlled by adjusting the pH value, and the pH value affects the morphology, size and luminescence properties of the product;

[0013] The precursor solution is subjected to a hydrothermal reaction to obtain an iridium and chromium co-doped long afterglow nanomaterial.

[0014] Preferably, the hydrothermal reaction conditions are: heating at 100-250° C. for 10 h.

[0015] Preferably, Zn 2+ , Ga 3+ ,Ge 4+ Cr 3+ and Ir 4+ The molar ratio is 3.54:4.35:0.27:0.03:0.2.

[0016] The present invention also protects the use of the above-mentioned iridium and chromium co-doped long afterglow nanomaterial in the preparation of afterglow imaging materials, peroxidase-like enzymes, photothermal conversion materials, photothermal imaging materials or electrocatalytic materials.

[0017] Preferably, the afterglow imaging material is a cell imaging material or a tumor imaging material, the cell imaging is afterglow imaging, and the tumor imaging is photothermal imaging.

[0018] Preferably, the electrocatalytic material is prepared according to the following steps: calcining the iridium and chromium co-doped long afterglow nanomaterial at 1000°C for 3-5h, then ultrasonically dispersing it in a mixed solution of ethanol and deionized water in a volume ratio of 1:2, and then taking 80μL to coat it on carbon paper, and repeating the dripping once after drying to obtain the electrocatalytic material.

[0019] Preferably, the electrocatalytic material undergoes an oxygen evolution reaction under the irradiation of light.

[0020] Compared with the prior art, the present invention has the following beneficial effects:

[0021] 1. In the iridium and chromium co-doped long afterglow nanomaterial of the present invention, iridium and chromium metals enter the zinc gallium germanate long afterglow nanomaterial system by doping, which effectively improves the peroxidase-like activity of the long afterglow nanomaterial and gives Ir(IV)-PLNPs the potential for photothermal conversion and photothermal imaging, as well as the potential for treating tumors; the afterglow imaging ability of the iridium and chromium co-doped long afterglow nanomaterial of the present invention enables nanomedicines to effectively label intracellular lysosomes, and then realize imaging of cells and tumors, realize imaging of cells through afterglow imaging, and realize imaging of tumors through photothermal imaging, and has the potential for treating tumors; and the afterglow of the long afterglow can be used to effectively improve the electrocatalytic performance under illumination. The present invention provides a new design method for developing safe and effective long afterglow nanomaterials with multiple functions.

[0022] 2. Considering that under the same synthesis conditions, due to the slow nucleation and growth of Ir, the present invention incorporates Ir into the chromium-doped zinc gallium germanate long afterglow nanomaterial. After doping, Ir has little effect on the size of the long afterglow nanomaterial. The small size of the nanoparticles enables them to penetrate biological barriers, such as cell membranes, and distribute more widely in the body, which makes them ideal carriers for drug delivery and bioimaging. In addition, Ir doping gives the long afterglow nanomaterial photothermal conversion capability.

[0023] The size of Ir nanoparticles is smaller than that of Pt nanoparticles, which prompted us to consider introducing Ir to construct PLNPs-based nanozymes. This PLNPs-based nanozyme has long-lasting near-infrared afterglow emission and red LED light renewability, which can be used for bioimaging and photoelectrocatalysis. The introduction of Ir gives the nanozyme the potential for photothermal conversion and peroxide-like activity, realizing potential applications in tumor imaging and tumor therapy.

[0024] 3. The present invention adopts the co-doping method for the first time to realize the co-doping of iridium and chromium in long afterglow nanomaterials, so as to introduce multiple elements at the same time, thereby realizing the multifunctionality of iridium and chromium co-doped long afterglow nanomaterials, and being able to introduce new elements without increasing the hydrodynamic diameter of the long afterglow nanomaterials and without affecting the surface accessibility.

[0025] The present invention firstly 2+ , Ga 3+ ,Ge 4+ ,Cr 3+ and Ir 4+ The ion solutions are mixed evenly, and then the metal cations are precipitated with ammonia water, followed by hydrothermal treatment to obtain iridium and chromium co-doped long afterglow nanomaterials. The obtained Ir(IV)-PLNPs ensure that all elements are evenly distributed, ensuring the stability of Ir(IV)-PLNPs. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1 This is a morphological characterization diagram of the chromium-doped long afterglow nanomaterial of Comparative Example 1 under a transmission electron microscope;

[0027] Figure 2 The lattice diagram of the chromium-doped long afterglow nanomaterial of Comparative Example 1;

[0028] Figure 3 This is the X-ray diffraction pattern of the chromium-doped long afterglow nanomaterial of Comparative Example 1;

[0029] Figure 4 This is a morphological characterization diagram of the iridium and chromium co-doped long afterglow nanomaterial of Example 1 under a transmission electron microscope;

[0030] Figure 5 The lattice diagram of the iridium and chromium co-doped long afterglow nanomaterial of Example 1;

[0031] Figure 6 This is the X-ray diffraction pattern of the iridium and chromium co-doped long afterglow nanomaterial of Example 1;

[0032] Figure 7 This is a full scan spectrum of the X-ray photoelectron spectrum of the iridium and chromium co-doped long afterglow nanomaterial of Example 1;

[0033] Figure 8 The high-angle annular dark field image-scanning (HAADF) transmission electron image of the iridium and chromium co-doped long afterglow nanomaterial in Example 1 and the element distribution diagram of Zn, Ga, Ge, Cr and Ir;

[0034] Fig. 9 The excitation-emission spectra of the chromium-doped long afterglow nanomaterial of Comparative Example 1 and the iridium and chromium co-doped long afterglow nanomaterial of Example 1;

[0035] Fig.10 This is the afterglow spectrum of the iridium and chromium co-doped long afterglow nanomaterial of Example 1;

[0036] Fig.11 This is an afterglow imaging diagram of the iridium and chromium co-doped long afterglow nanomaterial of Example 1 after being excited by a UV lamp for 5 minutes;

[0037] Fig.12 This is an afterglow imaging diagram of the iridium and chromium co-doped long afterglow nanomaterial of Example 1 after repeated excitation of LED light for 3 times;

[0038] Fig.13 Characterization diagram of the peroxidase-like activity of the chromium-doped long afterglow nanomaterial of Comparative Example 1, the iridium and chromium co-doped long afterglow nanomaterial of Example 1, and water;

[0039] Fig.14Characterization diagram of the peroxidase-like activity of the chromium-doped long afterglow nanomaterial of Comparative Example 1, the iridium and chromium co-doped long afterglow nanomaterial of Example 1, and water;

[0040] Fig.15 The absorption spectra of the chromium-doped long afterglow nanomaterial of Comparative Example 1 and the iridium and chromium co-doped long afterglow nanomaterial of Example 1;

[0041] Fig.16 The cytotoxicity of the iridium and chromium co-doped long afterglow nanomaterials to different cells in Example 1, wherein a is 4T1 cells, b is Hela cells, c is L929 cells, and d is U-87MG cells;

[0042] Fig.17 In the figure, white is a cell image labeled with cell bright field, lysotracker is a cell image labeled with commercial green fluorescent probe, Ir(IV)-PLNPs is a cell image labeled with iridium and chromium co-doped long afterglow nanomaterials in Example 1, merge is a superposition of a cell image labeled with cell bright field, commercial green fluorescent probe and a cell image labeled with iridium and chromium co-doped long afterglow nanomaterials in Example 1, and distribution is an intensity distribution diagram of Ir(IV)-PLNPs and lysotracker in a region of interest;

[0043] Fig.18 The photothermal images of tumor-bearing mice injected in situ with physiological saline and the iridium and chromium co-doped long afterglow nanomaterials of Example 1 before and after injection;

[0044] Fig.19 is the polarization curve of carbon paper;

[0045] Fig. 20 This is a polarization curve diagram of the iridium and chromium co-doped long afterglow nanomaterial of Example 1;

[0046] Fig.21 is the chronopotentiometry curve of carbon paper;

[0047] Fig. 22 It is a chronopotentiometry curve diagram of the iridium and chromium co-doped long afterglow nanomaterial of Example 1;

[0048] Fig.23 This is the chronopotentiometry curve of carbon paper within 12 hours;

[0049] Fig.24 This is a chronopotentiometry curve of the iridium and chromium co-doped long afterglow nanomaterial in Example 1 within 12 hours. DETAILED DESCRIPTION

[0050] The specific embodiments of the present invention are described in detail below, but it should be understood that the protection scope of the present invention is not limited by the specific embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work belong to the protection scope of the present invention. The experimental methods described in the embodiments of the present invention are conventional methods unless otherwise specified.

[0051] Compared with the PLNPs with chemical surface modification in the prior art, the present invention does not introduce functional groups, thus overcoming the defect that the functional groups cover the surface of PLNPs, thereby shielding the targeting molecules and causing non-specific binding.

[0052] Compared with the PLNPs coated in the prior art, the present invention uses Ir to directly and uniformly dope, so that the particle size of the iridium and chromium co-doped long afterglow nanomaterials is 10.2±2.3nm. After doping, Ir has little effect on the size of the long afterglow nanomaterials. The small size of the nanoparticles enables them to penetrate biological barriers, overcoming the problems of the prior art of efficient multimodal nanozymes based on PLNPs, such as increased hydrodynamic diameter and decreased surface accessibility after coating.

[0053] Compared with the prior art, the present invention provides a new preparation method and a new material Ir(IV)-PLNPs. While Ir(IV)-PLNPs have multiple functions, they overcome the technical defects of the prior art in modifying PLNPs and have broad application prospects.

[0054] The technical solution of the present invention is studied using embodiments and comparative examples below, and the specific research methods and results are as follows:

[0055] Example 1

[0056] A method for preparing an iridium and chromium co-doped long afterglow nanomaterial comprises the following steps:

[0057] S1, Zn 2+ , Ga 3+ ,Ge 4+ ,Cr 3+ and Ir 4+ The ionic solutions are mixed in H2O to form a homogeneous aqueous solution;

[0058] S2, adjusting the aqueous solution to pH 8.0 with 28% by volume ammonia water, and continuously stirring vigorously at room temperature for 3 h to obtain a precursor solution;

[0059] S3, the precursor solution was transferred to an autoclave lined with polytetrafluoroethylene, the autoclave was hydrothermaled at 200 °C for 10 h, washed twice with H2O and ethanol, and then dried to obtain Ir(IV)-PLNPs, whose molecular formula is Zn1.3 Ga 1.6 Ge 0.1 O4:Cr 0.0075 ,Ir 0.05 ;

[0060] The final concentrations of different metal ions were Zn 2+ (3.54mmol), Ga 3+ (4.35mmol), Ge 4+ (0.27mmol), Cr 3+ (0.03mmol) and Ir 4+ (0.2mmol).

[0061] Example 2

[0062] A method for preparing an iridium and chromium co-doped long afterglow nanomaterial comprises the following steps:

[0063] S1, Zn 2+ , Ga 3+ ,Ge 4+ ,Cr 3+ and Ir 4+ The ionic solutions are mixed in H2O to form a homogeneous aqueous solution;

[0064] S2, adjusting the pH of the aqueous solution to 8.5 with 28% by volume ammonia water, and continuously stirring vigorously at room temperature for 3 hours to obtain a precursor solution;

[0065] S3, the precursor solution was transferred to an autoclave lined with polytetrafluoroethylene, the autoclave was hydrothermaled at 250 ° C for 10 h, washed twice with H2O and ethanol, and then dried to obtain Ir(IV)-PLNPs, whose molecular formula is Zn 1.3 Ga 1.6 Ge 0.1 O4:Cr 0.0075 ,Ir 0.05 ;

[0066] The final concentrations of different metal ions were Zn 2+ (3.54mmol), Ga 3+ (4.35mmol), Ge 4+ (0.27mmol), Cr 3+ (0.03mmol) and Ir 4+ (0.2mmol).

[0067] Example 3

[0068] A method for preparing an iridium and chromium co-doped long afterglow nanomaterial comprises the following steps:

[0069] S1, Zn2+ , Ga 3+ ,Ge 4+ ,Cr 3+ and Ir 4+ The ionic solutions are mixed in H2O to form a homogeneous aqueous solution;

[0070] S2, adjusting the aqueous solution to pH 10.0 with 28% ammonia water by volume, and continuously stirring vigorously at room temperature for 3 hours to obtain a precursor solution;

[0071] S3, the precursor solution was transferred to an autoclave lined with polytetrafluoroethylene, the autoclave was hydrothermaled at 100 °C for 10 h, washed twice with H2O and ethanol, and then dried to obtain Ir(IV)-PLNPs, whose molecular formula is Zn 1.3 Ga 1.6 Ge 0.1 O4:Cr 0.0075 ,Ir 0.05 ;

[0072] The final concentrations of different metal ions were Zn 2+ (3.54mmol), Ga 3+ (4.35mmol), Ge 4+ (0.27mmol), Cr 3+ (0.03mmol) and Ir 4+ (0.2mmol).

[0073] Comparative Example 1

[0074] A method for preparing a chromium-doped long afterglow nanomaterial comprises the following steps:

[0075] S1, Zn 2+ , Ga 3+ ,Ge 4+ and Cr 3+ The ionic solutions are mixed in H2O to form a homogeneous aqueous solution;

[0076] S2. The aqueous solution was adjusted to pH 8.0 with ammonia solution, and was vigorously stirred at room temperature for 3 h to obtain a precursor solution;

[0077] S3, the precursor solution was transferred to an autoclave lined with polytetrafluoroethylene, the autoclave was heated at 200 ° C for 10 h, washed twice with H2O and ethanol and dried to obtain PLNPs. The chromium-doped long afterglow nanomaterials were Zn 1.3 Ga 1.6 Ge 0.1 O4:Cr 0.0075 ;

[0078] The final concentrations of different metal ions are Zn2+ (3.54mmol), Ga 3+ (4.35mmol), Ge 4+ (0.27mmol) and Cr 3+ (0.03mmol).

[0079] In order to more clearly understand the characteristics and advantages of the iridium and chromium co-doped long afterglow nanomaterials of the present invention, the Ir(IV)-PLNPs of Example 1 are taken as an example to compare with the PLNPs of Comparative Example 1, and are described in detail with reference to the accompanying drawings. The research methods and results are as follows:

[0080] like Figure 1 As shown, the PLNPs prepared in Comparative Example 1 have a relatively regular morphology; Figure 2 As shown, PLNPs have a distinct lattice structure; Figure 3 As shown, the XRD diffraction peaks of PLNPs correspond one to one with the lattice characteristic peaks of zinc germanate (JCPDS: 25-1018) and zinc gallate (JCPDS: 38-1240). The results show that the preparation method of the present invention successfully obtains a long afterglow nanomaterial with a typical cubic spinel structure.

[0081] like Figure 4 As shown, the morphology of Ir(IV)-PLNPs prepared in Example 1 is relatively regular. By randomly calculating 60 different particles, the particle size is found to be 10.2±2.3 nm. Figure 5 As shown in Figure 2, Ir(IV)-PLNPs have a distinct lattice structure. Figure 6 As shown in Figure 3, Ir(IV)-PLNPs have a standard cubic phase of zinc gallate (JCPDS file number 38-1240), and no obvious IrO2 and Ir characteristic peaks were observed, indicating that there are no large IrO2 and Ir particles in Ir(IV)-PLNPs. Figure 7 As shown in the figure, the XPS results show that Zn, Ga, Ge, O and Cr components are present in PLNPs and Ir(IV)-PLNPs, while Ir is only present in Ir(IV)-PLNPs. The ICP results further confirmed that the mass fraction of Ir in the Ir(IV)-PLNPs obtained in Example 1 is 0.8%. In order to observe Ir intuitively, EDS element mapping analysis was performed on Ir(IV)-PLNPs, as shown in the figure. Figure 8 As shown, EDS element mapping analysis revealed that Zn, Ga, Ge, O, Cr and Ir elements were uniformly distributed in Ir(IV)-PLNPs. The above results showed that Ir(IV)-PLNPs were successfully prepared.

[0082] PLNPs and Ir(IV)-PLNPs were dispersed in ultrapure water, and their fluorescence excitation and emission spectra were detected. Fig. 9 From the excitation and emission spectra shown in the figure, it was found that Ir(IV)-PLNPs had four larger fluorescence excitation peaks at 250nm, 410nm, 468nm and 554nm, and PLNPs and Ir(IV)-PLNPs had the largest emission peak at 694nm.

[0083] Ir(IV)-PLNPs were dispersed in ultrapure water and the afterglow spectrum was detected. Fig.10 The afterglow image of Ir(IV)-PLNPs shown in the figure shows that Ir(IV)-PLNPs exhibited an afterglow luminescence of 600s after being irradiated with 254nm UV light for 5min.

[0084] The afterglow signal of Ir(IV)-PLNPs was collected by a small animal imager, such as Fig.11 As shown in Figure 2, Ir(IV)-PLNPs can exhibit long-lasting afterglow luminescence after irradiation with 254nm UV light for 5min. Fig.12 As shown, Ir(IV)-PLNPs can recover their afterglow luminescence after repeated activation with 650nm LED light, which proves that Ir(IV)-PLNPs have good afterglow luminescence performance and are expected to achieve higher application value through in vivo and in vitro imaging.

[0085] The present invention also explores the peroxidase-like activity of Ir(IV)-PLNPs. The activity determination method is the tetramethylbenzidine (TMB) colorimetric method. This method utilizes the property that TMB will be oxidized into a blue compound in the presence of peroxidase and hydrogen peroxide. The formed blue compound has a maximum absorption peak at a wavelength of 652nm, and the depth of the color is proportional to the activity of the peroxidase. Specifically: an acetate buffer (0.2mol / L, 1.0mL, pH 3.6) containing Ir(IV)-PLNPs (200μg / mL), TMB (0.4mmol / L) and H2O2 (5mmol / L) was incubated at 37°C for 10min, and then the absorbance at 652nm was detected, with H2O and PLNPs as the control group. Fig.13 and Fig.14 As shown in Figure 2, compared with PLNPs and H2O, Ir(IV)-PLNPs showed good peroxidase-like activity, proving that its activity was mainly attributed to iridium metal. The absorption spectra of Ir(IV)-PLNPs and PLNPs were collected, as shown in Figure 2. Fig.15 As shown, compared with PLNPs, Ir(IV)-PLNPs have obvious absorption at 808 nm, indicating that Ir(IV)-PLNPs have the potential for photothermal conversion.

[0086] The above verification shows that Ir(IV)-PLNPs have multiple properties, including afterglow imaging capability, peroxidase-like activity, and photothermal conversion potential.

[0087] Mouse breast cancer cells (4T1 cells), human cervical cancer cell line (HeLa cells), mouse fibroblasts (L929 cells) and human brain glioblastoma cells (U-87MG cells) were incubated with Ir(IV)-PLNPs for 24 h and 48 h, respectively, and the cell activity was determined using the cell counting kit-8 (cck-8) reagent. Fig.16 As shown, even when the concentration of Ir(IV)-PLNPs was 200 μg / mL, the cell viability of the four cell lines remained above 80%, indicating that Ir(IV)-PLNPs had low cytotoxicity towards multiple cell lines.

[0088] After incubating HeLa cells with Ir(IV)-PLNPs for 1.5 h, the lysosomal green fluorescent probe (Lyso Tracker Green DND-26) produced by Thermo Fisher Scientific was added and incubated for 30 min, and then the labeling of the two fluorescent dyes on the cells was observed under a laser confocal microscope. Fig.17 As shown, under 488nm excitation light, the cells emit green fluorescence of the lysosomal green fluorescent probe, and under 552nm excitation light, the cells emit red fluorescence of Ir(IV)-PLNPs. Ir(IV)-PLNPs exhibited a strong afterglow signal in Hela cells, and significant overlap with green fluorescence was observed. In addition, the intensity distributions of Ir(IV)-PLNPs and lysotracker green in the region of interest (ROI) were also very synchronized. These results indicate that Ir(IV)-PLNPs are capable of cell imaging and labeling lysosomes.

[0089] To verify the in vivo photothermal imaging capability of Ir(IV)-PLNPs, Ir(IV)-PLNPs were injected into the tumor site of mice, and the control group was injected with saline. Then, images were collected on a thermal imager under 808 nm laser irradiation, such as Fig.18 As shown, the photothermal imaging effect of injected Ir(IV)-PLNPs was better and the temperature was higher, which has the potential for photothermal therapy.

[0090] From the above verification, it can be concluded that Ir(IV)-PLNPs can be used for cell imaging and in vivo photothermal imaging, and have the potential for photothermal therapy.

[0091] After calcining Ir(IV)-PLNPs at 1000°C for 3h, the powder was dispersed in a mixed solution of ethanol and deionized water with a volume ratio of 1:2, and then ultrasonically treated. Then 80μL of the mixed solution was dispersed on carbon paper (cp), dried, and repeated once for standby use. The electrochemical measurement data was completed by an electrochemical workstation. The prepared electrode was used as the working electrode (the control group was carbon paper), the Pt sheet was used as the counter electrode, and Hg / HgO was used as the reference electrode to assemble a three-electrode test system to study the catalytic performance of the working electrode alone. The electrolyte was a 1.0mol / L alkaline KOH solution, and the polarization curve was measured by linear voltammetry, such as Fig.19 The LSV curve of cp is shown, and Fig. 20 The LSV curve of the cp containing Ir(IV)-PLNPs shown in the figure shows that the oxygen evolution reaction effect of the cp containing Ir(IV)-PLNPs as an anode is poor.

[0092] In order to evaluate the effect of light on the cp working electrode containing Ir(IV)-PLNPs, a xenon lamp light source (4000 lux) was used to simulate sunlight irradiation on the working electrode, and the chronopotentiometry (VT) test was performed. The current was set to 1 mA, and the VT curve was collected for 30 minutes. Then, the xenon lamp light source was used to irradiate the working electrode for 30 minutes. After stopping the light, the VT curve was collected for 1 hour, and this was repeated three times. Fig.21 As shown, the VT curve of cp, and Fig. 22 The VT curve of cp containing Ir(IV)-PLNPs shown in the figure shows that the performance of cp and cp containing Ir(IV)-PLNPs as working electrodes will be improved under the irradiation of xenon lamp, and the performance of cp containing Ir(IV)-PLNPs will be improved more. After the light is stopped, the performance of cp deteriorates rapidly, while the performance of cp containing Ir(IV)-PLNPs as a working electrode deteriorates slowly, and the performance can be improved again under light, which is attributed to the response of Ir(IV)-PLNPs to light.

[0093] In order to evaluate the stability of cp and cp containing Ir(IV)-PLNPs, the VT (12 h) of two working electrodes was collected for testing. The current was set to 1 mA, such as Fig.23 The VT curve of cp shown, and Fig.24The VT curve of cp containing Ir(IV)-PLNPs is shown in Figure 1. cp has better stability as a working electrode. The stability of cp containing Ir(IV)-PLNPs is better in the first 6 hours, and then the stability deteriorates, which may be due to the shedding of Ir(IV)-PLNPs. It is proved that in the test of the effect of xenon light source on the working electrode, the performance improvement of cp electrode containing Ir(IV)-PLNPs under light is mainly attributed to the response of Ir(IV)-PLNPs to light.

[0094] The Ir(IV)-PLNPs of the present invention have multiple properties, can realize cell imaging and in vivo photothermal imaging, have the potential for tumor treatment, and can improve the oxygen evolution reaction effect of the working electrode under the irradiation of light.

[0095] When preparing Ir(IV)-PLNPs, different metal ions can also be doped into different long afterglow nanomaterials to monitor the distribution of drugs in real time and realize the potential ability of tumor treatment, as well as to improve the performance of oxygen evolution reaction in electrocatalysis; the doped metal ions include rare earth elements, such as Eu3 + , Tb 3+ 、Ce3 + 、Nd 3+ 、Sm 3+ 、Ho3 + , Er 3+ 、Tm 3+ ; Transition metal ions, such as Mn2 + ,Cu2 + 、Co2 + 、Ni 2+ ; Alkaline earth metal ions, such as Sr 2+ , Ba 2+ , Ca 2+ , it should be ensured that the long afterglow nanomaterial after doping has the same performance, including enzyme-like activity, photothermal properties and photothermal imaging capabilities. In addition, the zinc gallium germanate long afterglow nanomaterial of the present invention can also be replaced with other near-infrared long afterglow nanomaterials, such as ZnGa2O4:Cr 3+ ,Sn 4+ ;Li2CaSiO4:Eu 2+ ,Nd 3+ ;Ca 0.2 Zn 0.9 Mg 0.9 Si2O6:Eu 2+ ,Mn 2+ ,Dy 3 ; And it should be ensured that the long afterglow nanomaterials after doping can also emit near-infrared light and have a longer afterglow time.

[0096] It is understandable that many changes in details are possible, but this does not violate the scope and spirit of the invention. Any appropriate changes made to the invention by a person of ordinary skill in the art should be deemed to be within the scope of the patent of the invention.

Claims

1. An iridium and chromium co-doped long afterglow nanomaterial, characterized in that: Iridium and chromium co-doped long afterglow nanomaterials are iridium and chromium co-doped zinc gallium germanate long afterglow nanomaterials, and its molecular formula is Zn 1.3 Ga 1.6 Ge 0.1 O4:Cr 0.0075 ,Ir 0.05 .

2. The iridium and chromium co-doped long afterglow nanomaterial according to claim 1, characterized in that: The particle size of the iridium and chromium co-doped long afterglow nanomaterial is 10.2±2.3nm.

3. A method for preparing the iridium and chromium co-doped long afterglow nanomaterial according to claim 1, characterized in that: The steps include: Zn 2+ , Ga 3+ ,Ge 4+ ,Cr 3+ and Ir 4+ The ionic solutions are mixed in water to form a homogeneous aqueous solution; After adjusting the aqueous solution to a pH of 8.0-10.0 with aqueous ammonia, a precursor solution is obtained; The precursor solution is subjected to a hydrothermal reaction to obtain an iridium and chromium co-doped long afterglow nanomaterial.

4. The method for preparing the iridium and chromium co-doped long afterglow nanomaterial according to claim 3, characterized in that: The conditions of the hydrothermal reaction are: heating at 100-250°C for 10 h.

5. The method for preparing the iridium and chromium co-doped long afterglow nanomaterial according to claim 3, characterized in that: Zn 2+ , Ga 3+ ,Ge 4+ Cr 3+ and Ir 4+ The molar ratio is 3.54:4.35:0.27:0.03:0.

2.

6. Use of the iridium and chromium co-doped long afterglow nanomaterial according to claim 1 in the preparation of afterglow imaging materials, photothermal imaging materials, photothermal conversion materials or electrocatalytic materials.

7. The use according to claim 6, characterized in that: The afterglow imaging material is a cell imaging material or a tumor imaging material, the cell imaging is afterglow imaging, and the tumor imaging is photothermal imaging.

8. The use according to claim 6, characterized in that: The electrocatalytic material is prepared according to the following steps: calcining the iridium and chromium co-doped long afterglow nanomaterial at 1000° C. for 3-5 hours to obtain the electrocatalytic material.

9. The use according to claim 8, characterized in that: The electrocatalytic material undergoes an oxygen evolution reaction under the irradiation of light.

10. Use of the iridium and chromium co-doped long afterglow nanomaterial according to claim 1 in the preparation of peroxidase-like enzymes.

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