TW201116479A - Hydrophilic modified II-VI quantum dot and preparation thereof - Google Patents

Abstract

A hydrophilic modified II-VI group quantum dot comprises a core, first groups and at least one second group. The core is a nanoparticle containing a II-VI group compound. Each of the first group represents by the formula of -S-X1-Y1, X1 represents a divalent group and Y1 represents a hydrophilic group. The second group represents by the formula of -O3PH2-X2-Y2, X2 represents a divalent group and Y2 represents a functional group to be boned with a biocompatible molecule, with the proviso that the number of the first groups is greater than that of the second group. This invention also provides the preparation of the quantum dot. The hydrophilic modified II-VI group quantum dot of this invention exhibits an excellent hydrophilicity to be well dispersed in an aqueous phase and a better photoluminescent intensity, and is also useful for the biomedical field.

Description

201116479 VI. Description of the Invention: [Technical Field] The present invention relates to a quantum dot and a method for producing the same, and more particularly to a hydrophilic modified π_νι family of quantum dots and a method for preparing the same.曰[Prior Art] Most of the baryon points are II-VI or ιπ_ν. The semiconductor nano: particles 'have significant quantum limitations due to their size characteristics: should be (quantum Confinement effect), stimulated by the same laser Next, due to the particle size, he emits different colors of light 'in addition' compared to the conventional one: fluorescent dyeing 'quantum dots have flicker (high brightness, high photochemical stability, higher excitation spectrum, higher (four) light f Sub-efficiency 1 single-wavelength laser (4) Excitation of quantum dots of (4) emits multiple wavelengths of emitted waves, narrow and symmetrical symmetry of the transmitted wave, and repeatable excitation, making quantum dots extremely useful in the application of biomedical and optoelectronic components. Potential and development value. "Due to the fact that Xia Zi points mostly use hydrophobic solvents in the synthesis, the surface of the quantum dots produced is mostly hydrophobic (as shown on the left side of the arrow in Figure i), and cannot directly interact with biomolecules. Before the application of the raw f, the surface of the quantum dot must be modified to be hydrophilic so that it can directly enter the cell or adsorb on the cell surface. However, the group attached to the surface of the particle can also be used with the nanomedicine. The combination of the monthly b-force 'allows the $ sub-point to enter - step for biomedical examination, diagnosis and treatment. At first glance, 'to synthesize stable hydrophilic quantum dots (or called the water phase quantum straight - a tricky The problem, but in general, can be modified by the surface of the hydrophobic ionic point - a layer of hydrophilic substances f, such as thiol compounds _), polymers (P〇lymers) and lumps (ph〇sph〇ii (four), etc. 201116479 Referring to Figure 1, there are three main ways to synthesize aqueous quantum dots: (I) Ligand exchange: mainly replacing the quantum dots with the sulfhydryl terminal (-SH) containing a sulfhydryl compound. The hydrophobic substance on the surface is bonded to the surface of the quantum dot, and the carboxyl group (-COOH) at the other end is a hydrophilic ligand, and provides the surface charge of the quantum dot, so that the quantum dot can be stably dispersed in the aqueous solution. Silica encapsulation: a glass-like structure dominated by cerium oxide is added to the surface of a quantum dot with a sulfhydryl group to increase the hydrophilicity of the quantum dot. (III) Hydrophobic effect Hydrophobic interaction: profit A polymer or phospholipid having a dimorphic end, tightly embedded in the outer layer of the nano quantum dot, and utilizing the hydrophilic outer end to improve the hydrophilicity of the quantum dot. Although the quantum of the aqueous phase can be synthesized by the foregoing manner Point, but the method (I) to modify the surface of the quantum dot with a mercapto compound can significantly reduce the quantum yield of photoluminescence (PL), and the outer layer of the molecule formed by the method (II) is a branch The cross-linked structure makes the particle size larger and easily generates interparticle reactions. In order to avoid mutual reaction between the particles, the quantum dots must be controlled at extremely low concentrations, and the method (III) is to modify the polymer on the surface of the quantum dots. Although (polymers) or lipid-filling can prevent a decrease in the quantum efficiency of PL, the particles are made larger, and it is difficult to carry out research based on fluorescence resonance energy transfer, and it is difficult to develop the applicability. In addition to the above disadvantages, since the conventional method of synthesizing hydrophilic quantum dots 201116479 is to first synthesize hydrophobic quantum dots, and then surface-modifying the hydrophobic quantum dots to convert them into hydrophilic quantum dots, relatively more manufacturing is required. The steps take more time and have a lack of manufacturing efficiency. SUMMARY OF THE INVENTION Accordingly, it is an object of the present invention to provide a hydrophilic modified II-VI quantum dot which is capable of being stably dispersed in an aqueous phase and having better photostability and which can be directly synthesized. . Thus, the modified Πνν family of quantum dots of the present invention comprises a core, a plurality of first groups bonded to the core, and at least one first group bonded to the core. The core is a nanoparticle containing a Group II-VI compound. Each of the first groups is represented by an S-X1 - γ χ, χ 1 represents a divalent linking group, and Υ 1 represents a hydrophilic group. The second group is represented by _〇3ΡΗ2_χ2_γ2, χ2 represents a linkage group, and γ2 represents a guana b group capable of binding to a biocompatibility molecule, provided that the number of the first group is greater than the The number of second groups. The hydrophilic modified π_νι group quantum dots of the present invention are modified by a plurality of first groups and at least one second group on the surface of the core containing the π-νι compound, the bundle ends of the first groups Γ1 is a hydrophilic group, which is beneficial to make the neutron point have excellent hydrophilicity and can be stably dispersed in the water phase; the 基=0 bond of the second group can effectively protect the core, so that the quantum efficiency is not changed by the external environment. And attenuation, in addition, it is worth mentioning that the hydrophilic groups of the first group and the terminal Υ2 of the second base map are biocompatible molecules (such as proteins, antibodies, amino acids and DNA). The combination of functional groups is thus more conducive to the application in the field of biomedicine. 201116479 The present invention also provides a method for preparing the hydrophilic modified ιι_νι group of quantum dots, and comprises the following steps: (i) using a -π group ion source and a mercapto gr〇Up compound under an inert gas atmosphere; 'a phosphonic acid compound and water are mixed to obtain a first reaction liquid; (π) to prepare a second reaction liquid containing a -νι ion source and water; (iii) Mixing the first reaction liquid with the second reaction liquid to obtain a mixture, and subjecting the mixture to a nucleation reaction at a temperature lower than 1 〇〇〇c; and (iv) purifying the mixture after the reaction to The hydrophilic modified II-VI quantum dots are prepared. The hydrophilic modified II-V of the present invention: [The method of preparing a family of quantum dots can directly synthesize II-V in the aqueous phase: [group quantum dots] can effectively improve process efficiency. [Embodiment] The above-mentioned "the number of the first groups is larger than the number of the second groups" means that the number of the first groups contained in each quantum dot is larger than the number of the second groups. The amount of the first group and the second group is mainly adjusted by the molar ratio of the mercapto group-containing compound and the phosphonic acid compound in the first reaction liquid. Preferably, the ratio of the first group to the second group is in the range of about 5:1 to 8:1. In the first group, the χ1 of -s_xl-γ1 may be any suitable divalent linking group. . Preferably, hydrazine is selected from the group consisting of unsubstituted alkylene, substituted alkylene, _c〇_, —(c=〇)〇, ◦(CO) phenyl phenylene ), biphenyleny D or a combination of these; more preferably, χ 1 is an unsubstituted swellable group. The unsubstituted extension group is, for example, but not (d) Ci~Ci 〇 烧, 201116479 . Preferably, the alkyl group of C2 to C1() is substituted, and the substituted alkyl group is, for example, but not limited to, a C 丨~c1G alkyl group substituted by a phenyl group, and a Ci~CiG alkyl group substituted by an amine group. This specific combination means that each of the substituents listed above may be arbitrarily combined into one divalent linking group. Y1 may be any suitable hydrophilic group, and preferably may be a hydrophilic group having a binding ability to a biocompatible molecule. Preferably, γΐ is selected from a carboxyl group, a trans group or an amine group; in one embodiment of the invention, γΐ is a slow group. Preferably, each first group is composed of —s(CH2)mCOOH As shown, m = 2 to 10. In one embodiment of the present invention, each of the first groups is an S(CH2)2COOH. In the second group, X2 of -3PHr-X2-Y2 Is any suitable divalent linking group. Preferably, X2 is selected from an unsubstituted alkylene group, a substituted alkylene group, -CO-, -(c=o)o-, -〇(c) =o)_, _〇-, a stupid base, a biphenyl group or a combination thereof; more preferably, X2 is a Cl~C3 alkyl group, -CO-, -〇-, a phenyl group, a stretch Biphenyl, _CH(NH2)- or xylylene. Y2 is a functional group capable of binding to a biocompatible molecule, preferably γ2 is selected from an amine group or a phosphonium group. (phosphono, -H2P〇3). Preferably, the second group is selected from the group consisting of 〇3ph2(ch2)xh2po3, a 03PH2C6H4C6H4H2P03, -O3PH2OH2PO3, -03PH2CHNH2H2P03, -03PH2CH2CH2NH2, 〇3PH2CH2C6H4CH2H2P〇3 or —〇 3PH2(C=0)NH2, x=l~3; in one embodiment of the invention, the second base is -〇3PH2(CH2)2H2P03. Preferably, the II-VI compound is selenized. Preferably, the quantum dots have an average particle diameter of 3 nm to 5 llm. Preferably, the hydrophilic modified II-VI quantum dots are obtained by using a Group II ion source. Ion source And a monophosphonic acid compound is mixed to obtain a first reaction liquid, and then the first reaction liquid is reacted with a Group VI ion source, wherein the mercapto group-containing compound is represented by HS—X —γ丨. The phosphonic acid compound is represented by QJK-X2-γ2, and the definitions of X1, X2, Y1 and Y2 are as described above, respectively. The structure of the hydrophilic modified Π_νι family of quantum dots of the present invention is presumed to be as shown in FIG. 2, which comprises a core 1, a plurality of first groups 2 bonded to the core nucleus, and at least one and the core. 1 combined with the second group 3. It should be noted that the number of the first group 2 and the second group 3 shown in 2 is only an example, and the scope of the invention cannot be limited thereto, and the number of the first group 2 and the second group 3 is only It suffices that the number of the first group is greater than the number of the second group, but it is preferable that the first group 2 and the second group 3 are distributed around the core 1. The hydrophilic (4) „, the family quantum dots belong to the aqueous phase quantum dots ′ can usually be stored in an experimental environment. Preferably, the quantum dots can be stored in an aqueous solution of pH 8 to pH 10. In the method of the invention, the adjustment and the change of the steps may be performed according to actual needs. Preferably, in the step (1), the mixed molar ratio of the sulfonate-containing compound and the phosphonic acid compound of the "group ion source" is 5 ·· 5 : 8 : ^. In one embodiment of the present invention, the mixed molar ratio of the π-group ion source, the 473-based compound, and the phosphonic acid compound is 8:8:1. 201116479 This Group II ion source is an element or compound selected to provide Group IIB ions. Preferably, the Group II ion source is a source of cadmium ions; more preferably, the Group II ion source is cadmium chloride (CdCl2). Preferably, the mercapto group-containing compound is represented by HS-X1-Y1, X1 represents a divalent linking group, and Y1 represents a hydrophilic group. More preferably, the thiol-containing compound is HS(CH2)mCOOH, m = 2 to 10. In a specific embodiment of the present invention, the mercapto group-containing compound is HS(CH2)2C〇〇H, that is, mercaptopropionic acid. Preferably, the phosphonic acid compound is represented by 03ΡΗ3-X2-Y2. X2 represents a divalent linking group and Y2 represents a functional group which can bind to a biocompatible molecule. More preferably, the phosphonic acid compound is selected from the group consisting of OP(OH)2(CH2)xH2P〇3, op(oh)2c6h4c6h4h2po3, OP(OH)2OH2P〇3, op(oh)2chnh2h2po3, OP(OH)2CH2CH2NH2 Op(oh)2ch2c6h4ch2h2po3, and 0P(0H)2(C=0)NH2, x=l~3. Preferably, the inert gas of the step (i) is nitrogen.

The group VI ion source of the step (ii) is an element or a compound which can provide a group VIB ion. It should be noted that when the ion source is a group VIB element, the reduction reaction is first performed to be a group VI ion. source. Preferably, the Group VI ion source of the step (ii) is obtained by a reduction reaction of a Group VI element with a reducing agent. In this reduction reaction, the molar ratio of the group VI element to the reducing agent is recommended to be 1:2, and the molar ratio range of the group VI element to the group II ion source is recommended to be 1:5 to 1:8. In one embodiment of the invention, the group VI element is selenium, and the reducing agent is sodium borohydride, and the VI 10 201116479 family ion source is sillicil sodium. Preferably, the molar ratio of the Group II ion source of the step (1) to the Group VI ion source of the step (ii) ranges from 5:1 to 8:1. Preferably, in the step (iii), the second reaction liquid is poured into the first reaction liquid to form a mixture, and the mixture is continuously heated for a period of time at a normal pressure and a temperature lower than 10 ° C. , cool to room temperature. More preferably, the reaction temperature ranges from 40 to 95 ° C; in one embodiment of the invention, the reaction temperature is 90 ° C. The purification step of the step (iv) can be adjusted and changed according to actual needs. Preferably, the purification step of the step (iv) is completed by adding the mixture to a precipitate, followed by centrifugation, filtration and drying. . Preferably, the process further comprises a step (v) after the step (iv), wherein the hydrophilic modified II-VI quantum dot is placed in an aqueous solution having a pH of 8 to 10. in. In one embodiment of the invention, the quantum dots are stored in a solution of Φ (Hydroxymethyl) aminomethane-HCl, Tris-HCl, Φ at pH 8.8. The invention is further illustrated by the following examples, which are to be construed as illustrative and not restrictive. <Examples> Preparation of CdSe quantum dots modified by MPA and EDPA (1) Weighing 0.046 g (0.2 mmol) of cadmium chloride (CdCl2 · H20) and 17 pL (0.2 mmol) of Mercaptopropionic acid, respectively. Abbreviated as MPA), 0.00475g (0.025 mmol) of ethyl bisphosphonate

L SI 11 201116479 (ethylenediphosphonie acid, EDPA for short), and 20mL of water, placed in a 50ml three-necked flask, and the three-necked flask is filled with nitrogen, stirred for 30 minutes, the above reagents are mixed evenly to prepare The first reaction liquid. (ii) Take 0.0079 g (0.1 mmol) of elemental selenium (Se) and 0.0123 g (0.2 mmol) of sodium hydride (NaBH4), and place it in a 10 mL double-necked flask to remove water by vacuum system. After the gas was withdrawn, the nitrogen system was turned on and then 1 mL of water was injected to make Se a colorless NaHSe solution, and a clear second reaction liquid was prepared. (iii) in a normal pressure environment, a second reaction solution of 0·25 ιη1 is rapidly injected into the first reaction liquid to form a mixture, and the mixture in the three-necked flask is changed from clarification to yellow and then orange to allow the reaction. After continuing and heating at a temperature of 90 ° C for 270 minutes, the temperature was lowered to room temperature. (iv) adding the reacted mixture to a mixture of acetone/ethanol for purification, in which case a phenomenon of precipitation of minute solid matter is observed, and the precipitated substance should be a quantum dot, and then, at 4000 r. The centrifugal speed is centrifuged to precipitate the precipitated material for centralized collection. After the centrifugation is completed, the supernatant is poured off, and then the acetone solution is added to wash the quantum point of the sink and centrifuged again. After the centrifugation was completed again, the supernatant liquid was poured off, and acetone remaining on the quantum dots was blown off with nitrogen. Finally, the MPA and EDPA modified CdSe quantum dots of the examples were prepared. (v) The quantum dots of the examples were dissolved in a Tris-HCl solution of pH 8.8 to obtain a CdSe quantum dot solution modified with MPA and EDPA. 0 12 201116479 <Comparative Example> The CdSe quantum dot solution was mixed with MPA, CdCl2.H20 and NaHSe at a molar ratio of 8:8:1 to obtain a reaction liquid. The pH of the reaction mixture was adjusted to 11 by using a 1 M aqueous solution of sodium hydroxide, and then the reaction mixture was subjected to a reaction at 150 ° C to obtain an MPA-modified CdSe quantum dot solution. [Test] 1. Light absorption and fluorescence spectrum measurement

The quantum dot solution prepared in the examples and the comparative examples was measured by an ultraviolet-visible spectrometer and a fluorescence spectrometer (Model: Thermo Spectronic, Aminco Bowman® Series 2 Luminescence Spectrometer), and the results are shown in Figures 3 and 4, respectively. Curves A1 and A2 show the test results of the light absorption rate and curves B1 and B2 show the test results of the fluorescence intensity. (Results) As shown in Fig. 3, the curve A1 shows that the quantum dot solution of the example has good light absorption at 400 nm to 550 nm, for example, 'having a light absorptance of about 0.1 aU at a wavelength of 500 nm, indicating that the quantum dot has Wide excitation spectrum. In addition, when the quantum dot solution of the example is irradiated with a Xenon lamp of a single wavelength (wavelength value of 365 nm), curve B1 shows the full-width half-maximum of the fluorescence spectrum emitted by the excited quantum dot (Full-Width Half-Maximum, Abbreviated as FWHM) is only 47 nm, its peak position is about 522 nm, and the spectrum is narrow and symmetrical, indicating that the quantum dots produced by the method of the present invention can exhibit stable and easily discernable emission spectra and are suitable for tracking. Mark, and 13 201116479 has potential applications as biomolecule calibration and detection. Compared with the comparative example, the light absorption rate of the quantum dot solution of the comparative example is significantly lower than that of the curve A2 of FIG. 4, for example, having a light absorption rate of 〇.〇2 au at a wavelength of 500 nm, thus demonstrating the implementation. The quantum dot solution has a better light absorbance. Referring again to curve B2 of Figure 4, the highest peak position of the fluorescence intensity at 555 nm' is clearly different from the examples, showing that the quantum dots of the present invention differ from the MPA-modified CdSe quantum dots. 2. Preservation of the pjj value of the solution According to the steps (i) to (iv) of the examples, the quantum dots are prepared, and the prepared CdSe quantum dots modified by MPA and EDPA are separately stored at pH 7 73, pH 8.2 and In a Tds-HCl solution of pH 8.8, the quantum dots stored in the above three solutions were respectively irradiated with laser light having a wavelength of 365 nm to measure the fluorescence spectrum of the emitted light, and the results are shown in Fig. 5. (Results) In Figure 5, it is shown that the higher the pH value, the higher and significant fluorescence intensity can be measured. During the experiment, the quantum dots are also tried to be stored in a solution with a pH below 5, and the measurement is performed. The fluorescence spectrum of the obtained fluorescence is low and inconspicuous, and there is a phenomenon of Lu precipitation, which indicates that the quantum dots are unstable under acidic conditions, so that the fluorescence is weakened or even disappeared in the acidic solution. 3. Quantum dot particle size measurement The high-resolution penetrating electron microscope (曰本, model: je〇l JEM-2010) was used to observe the quantum dot solution prepared in the examples and comparative examples. 6 and 7 are shown. (Results) 14 201116479 It can be seen from Fig. 6 that the particle sizes of the extracts 2 are fairly uniform and there is no K 'eye shape' indicating that the quantum dots can be stably dispersed in water, and the::-to-predetermined region After the quantum dots were respectively measured for their particle diameters and counted, it was shown that the average particle diameter of the quantum dots of the present invention was 3η. Take t: in the case of the quantum dot of the comparative example shown in the example of 'the same as '7', there is a significant clustering situation' and it is impossible to disperse the water in the water. This further demonstrates that the quantum dots of the present invention have the advantage of being stably dispersed in water. 4· Light stability measurement

The 65 nm 0 laser light is an excitation light source, and the quantum dot solution prepared in the examples is continuously irradiated, and the intensity of the emitted light (peak position at 522 nm) is measured every 1 hour, and held for 6 hours, at the beginning. The light intensity of the radiation is taken as a standard value, and the fluorescence intensity measured at other time points is separately divided from the initial standard value, and the measurement result is shown in FIG. (Results) < As shown in Fig. 8, after 6 hours of display, the luminescence intensity decay rate of the quantum dot solution after illuminating is only 彳2, and has better = light stability, when further When the quantum dot solution is applied to the test analysis, if a long test analysis time is required, a stable and easily discriminable measurement result can be obtained. 5. The quantum yield measurement is based on coumarinKin Et〇H, and the quantum efficiency value of the standard is known to be 73%. The standard was diluted to five different concentrations of samples c", c_2, c_3, c_4, and c_5, and the samples c-丨~c_5 were irradiated with a 365 nm light source to measure the coumarin- in the sample of 201116479. The absorption area under 365 nm and the integral area under the curve of the fluorescence spectrum (wave peak is 443 η ΐ η) emitted by _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ Taking the absorptivity of the table ι as the abscissa yi, the integral area of the f-light spectrum is the ordinate and the plot, and the result shown in Fig. 9 is obtained. The relationship of the straight line by linear regression is yi = 1218.2Xl 'slope The value is 1218·2, and the line is “ο%”. _ Table 1 sample number different concentration coumarin_l absorption rate (@365mn) ^ measurement result __ light spectrum integral 'C-1 0.1597 __V ^ ^ 11111 ) 189.10339 _C-2__- C^3 ------ _0. 1448 〇T〇84 175.0943 ^_ 109.43863 C-4 0.112 141.33698 C-5 0.0642 76.829986 In addition, the quantum dot solution prepared in the examples was diluted with water into five different concentrations of samples cn, CdSe_2, CdSe_3, CdSe_4 and

CdSe-5, and irradiated the sample cdSe-Kdk with a 365 nm light source, respectively, to measure the absorption rate of the quantum dots in the samples at 365 nm, and the fluorescence spectrum emitted after the 365 nm light source was irradiated (the peak was 522 nm). The area of the accumulated knife under the curve is shown in Table 2. Taking the absorption rate of Table 2 as the abscissa and the integral area of the fluorescence spectrum as the ordinate plot, the result shown in Fig. 1〇 can be obtained. The relationship of the straight line obtained by linear regression is 丫2=987.43 heart, slope value For 987.43, the R2 of the line is 〇9732. r--_Table-2 The amount of quantum dots with different concentrations. Measurement results Sample number absorption rate (@365nm) Fluorescence spectrum integral area (52 Onm) CdSe-1 ί 0.2759 274.0657 ~~~— CdS c-2 0.241 236.99722 16 201116479

CdSe-3 0.2145 219.46167 CdSe-4 0.2983 290.29068 CdSe-5 0.2603 254.76456 The quantum efficiency of the quantum dots prepared in the examples can be calculated by the following formula (refer to Joseph R. Lakowicz, J. C/zem· B1999, 103, 7613- 7620). ):

OcdSe = Ost (GradCdSe /Grad st)(t!2h2〇/ η2Εί〇Η)

Where 〇cdse is the quantum efficiency of the quantum dot, 〇st is the quantum efficiency of the coumarin-1 standard (ie 73%), GradCdSe is the slope value of the line of Fig. 10, GradST is the slope value of the line of Fig. 9, ηΗ2〇 = 1.3330, which is the refractive index of water used to dilute the quantum dot solution, ηΕίΟΗ = 1.3618, which is the refractive index of ethanol used to dilute the coumarin-1 standard. After all the known values were substituted into the above formula, the quantum yield of the quantum dots was calculated to be 68.94%. The MPA and EDPA modified CdSe quantum dots of the examples were compared with other documents calculated in the same manner and by the formula, and the results are shown in Table-3 (document A is 3^7(3/.(^/^^ .2006,78,321;Document B is Nanotechnolog.,2008, 19,475401; Document C is 乂P/zp. C/zem. C., 2008, 112, 1744): Table-3 Document A Document B Document c Example Quantum dot type CdSe CdSe CdSe/ZnS (core/shell) CdSe quantum dot modified by MPA and EDPA quantum efficiency 1% 12% 〜50% 68% (Results) From the results of Table 3 above, the MPA of the example and The CdSe set point of EDPA modification 17 201116479 does have better quantum efficiency, which proves that the modified hydrophilic Π_νι quantum dots of the present invention are effectively modified by the majority of the first group and at least the second group. Increasing quantum efficiency. In summary, the hydrophilic group of modified II-VI quantum dots of the present invention is modified by multiple, one-group and at least one second group, so that the quantum dots of the present invention are excellent. It is hydrophilic and not easy to aggregate, and it has better light is, 疋f, fluorescence intensity and quantum effect. And because the terminal of the first group and the second group belong to a functional group capable of binding to a biocompatible molecule, it is more effectively applied to the field of biomedicine. The method of the invention has the advantages of simplicity, low preparation cost, and the like. The nature of the quantum dots can be adjusted according to actual needs, thereby effectively expanding the scope of application. The above is only the preferred embodiment of the present invention, and the scope of the present invention is limited thereto. Inventive application: The simple equivalent changes and the dances made by Li Weiwei and the description of the invention are still within the scope of the patent of the present invention. [Simplified illustration] _ Figure 1 is a schematic diagram illustrating the existing synthetic aqueous phase The way of quantum dots means the ligand exchange method, the surface dryness _ table-rolling enthalpy embedding method and (III) means the hydrophobic force method; FIG. 2 is a schematic view showing the hydrophilic 经_νι of the present invention. Figure 3 is a graph of the absorption and glory spectrum of the invention. The CdSe quantum dot spectrum of the present invention and the EDpA modification; the absorption spectrum of the S卞 point ♦ liquid and the fluorescent light 18 20 1116479 FIG. 4 is an absorption and fluorescence spectrum illustrating the absorption spectrum and fluorescence spectrum of the MPA-modified CdSe quantum dot solution of the comparative example; FIG. 5 is a fluorescence spectrum diagram illustrating the MPA of the embodiment of the present invention. Fluorescence spectrum of EDPA-modified CdSe quantum dot solution measured in different pH solutions; Figure 6 is a transmission electron micrograph illustrating the MPA and EDPA modified CdSe quantum dot solution of the present invention. Figure 7 is a transmission electron micrograph showing the appearance of a MPA-modified CdSe quantum dot solution of a comparative example; Figure 8 is a graph illustrating the MPA and EDPA-modified CdSe quantum dots according to an embodiment of the present invention. The fluorescence intensity emitted by the solution decays with time; FIG. 9 is a linear relationship diagram illustrating the relationship between the absorption rate of coumarin-1 at different concentrations and the integrated area of the radiation spectrum; and FIG. 10 is a straight line diagram illustrating The quantum dot of the embodiment of the present invention is prepared by the absorption ratio of different concentrations and the area of the integrated area of the emitted fluorescence spectrum. 201116479 [Description of main component symbols] 1 .......... core core 3 .... ...the second group 2 ···......the first group

20

Claims (1)

201116479 VII, the scope of application for patents: 1. - species: water-based repair „, family quantum dots, including: two cores, is - nano-particles containing n-VI compounds. The number of eves with the surface of the core. The group is made by, ... the group 'the parent' P is a hydrophilic group; and the x represents a divalent linking group and the Υι table at least - if a second group is bonded to the surface of the core, the group is composed of 〇3ΡΗ2~χ2—γ2 • ± No, X represents a divalent linking group and Υ2:: a functional group bonded to a biocompatible molecule, provided that the number of the first group is greater than the number of the second group. 2. According to the first aspect of the patent application, the hydrophilic modified „-VI, the sub-points, wherein Χ1 and X2 are respectively selected from an unsubstituted alkylene group, a substituted alkyl group, -CO-, -(c=〇)〇—, _〇(c=〇) I, -ο-, phenylene, phenylene or a combination of these. The hydrophilic (4) family of quantum dots described in the above, wherein γ1 is selected from a slow group or a via group. 4. The hydrophilic (4) leg family quantum according to the scope of the patent application. , point, wherein each first group is represented by a yoke machine (7) (10), m = 2 ~ l 〇 5. The hydrophilic modified π_νι family of quantum dots according to the scope of claim 2, claim 2 And wherein the second group is selected from the group consisting of a hydrophilic group or a phosphinium group. 〇3PH2(CH2)xH2P〇3 , -〇3PH2C6H4C6H4H2P〇3 , 21 ί SI 201116479 -Ό3ΡΗ2〇Η2Ρ〇3 , -O3PH2CHNH2H2PO3 , —q3ph2ch2ch2nh2 , —o3ph2ch2c6h4ch2h2po3 or ~03 PH2(C=〇)NH2, X=1 〜3. 7. The hydrophilic modified π_νι 知子子点 according to the scope of claim ii, wherein the tvj compound is cadmium selenide. According to the scope of the patent application, the modified π_νι square ylide having hydrophilicity occupies an average particle diameter of 3 nm to 5 nm of the '5 hai I sub-point. 9' according to claim i of the patent scope The hydrophilic modified π_νι 夭 子 is obtained by mixing a steroid source, a wei group-containing compound and a monophosphonic acid compound to obtain a first reaction solution, and then the first reaction solution and the VI group ion The source is subjected to a reaction, wherein the mercapto group-containing compound is represented by HS—X1—Υ1, χΐ represents a divalent linking group, and Υ represents a hydrophilic group. The phosphonic acid compound is represented by 〇3ΡΗ3__χ2−γ2, X The non-divalent linking group and Υ2 represent a functional group Ρ 1 - a hydrophilic modified π-νι group quantum dot which can be combined with a biocompatible molecule, and comprises the following steps: (i) in an inert gas atmosphere Next 'will be a steroid source, a thiol-containing compound, a phosphine The acid compound and water are mixed to obtain a first reaction liquid, (11) a second reaction liquid is prepared, the second reaction liquid contains a Group VI ion source and water; (iii) the first reaction liquid and the The second reaction liquid is mixed to obtain a mixture, and then the mixture is subjected to a nucleation reaction at a temperature of less than 10 〇cC, 22 201116479; and (iv) the mixture after the reaction is purified to obtain the hydrophilicity. Modified II-VI quantum dots. 11. The method for producing a hydrophilic modified π_VI family of quantum dots according to claim 1, wherein in the step (1), the π-group ion source, the thiol compound, and the phosphonic acid compound The molar ratio of the molars is 8:8:1°. 12. According to the method of claim 1 of the patent application, the hydrophilic method is modified, wherein the group II ion is prepared. The source is a source of cadmium ions. 13. The method according to claim 1, wherein the mercapto group-containing compound is represented by HS—X1—Υ1, and χΐ represents a divalent linking group and Γ1 represents a hydrophilic group. 14. The method of preparing a hydrophilic modified group VI quantum dot according to claim 13, wherein the mercapto group-containing compound is HS(CH2)mCOOH, m=2 to 10. The method for producing a hydrophilic modified group VI quantum dot according to the first aspect of the patent application, wherein the phosphonic acid compound is represented by 〇3PH3—χ2-—Y2, and X2 represents a divalent linking group. And Y2 represents a functional group that can bind to a biocompatible molecule. The method for preparing a hydrophilic modified II group VI quantum dot according to claim 15, wherein the phosphonic acid compound is selected from the group consisting of 〇P(〇H)2(CH2)xH2P〇3 〇P(〇H)2C6H4C6H4H2P〇3, 〇P(〇H)2OH2P〇3, 0P(0H)2CHNH2H2P0, Ο Λ 23 201116479 OP(OH)2CH2CH2NH2 >〇P(〇H)2CH2C6H4CH2H2P〇; and 0P( 0H) 2 (C = 0) NH2, x = i ~ 3 17. The method for preparing a hydrophilic modified VI group quantum dot according to the 1G item of the 4th patent scope 'where the νι group ion of the step (9) The source is obtained by a reduction reaction of a -VI group element with a reducing agent. 18. According to the hydrophilic modified VI group quantum dot according to Item 17 of the Chinese patent scope, the ratio of the molar amount of the group VI element to the reducing agent is 1: 2. 19. According to the patent application, Λ = 围 = dried mate 10, the method of making hydrophilic modified VI-group quantum dots, the Gans Yi method, 'the group II ion source and the group VI ion source The molar ratio ranges from 5:1 to 8: i. 2 根据· According to the scope of the patent application ] The method for preparing a hydrophilic modified VI group quantum dot according to the seventh item, Li Shiyan, in which the group VI element is selenium, and the reducing agent is sodium borohydride, 哕The VT p ^ to 4 VI ion source is sodium selenide. 21. According to the method for preparing a hydrophilic modified π_VI family of quantum dots according to claim 0, in the squad, the purification step of the step (iv) is to add the mixture by the zinc. In the liquid solution, centrifuge, filter and dry coal. 22. The method for preparing a hydrophilic modified Π_VI quantum dot according to the scope of the patent application Λ7Τ θ θ, comprising a step (V) after the step (iv), the step (v) The hydrophilic modified II-VI quantum dots are placed in an aqueous solution having a pH of 8 to 10. In the method of preparing a hydrophilic modified VI group tweezers according to the patent application scope ντ ^ 2, the "dry' solution is a Tris-HCl solution. The method for producing a hydrophilic modified II-VI quantum dot according to claim 10, wherein the reaction temperature in the step (iii) is in the range of 40 ° C to 95 ° C. 25