METAL PARTICLE-LOADED HOLLOW MESOPOROUS ORGANOSILICA NANO/MICROPARTICLES AND METHOD FOR MANUFACTURING SAME
20220023841 · 2022-01-27
Inventors
Cpc classification
B01J13/203
PERFORMING OPERATIONS; TRANSPORTING
B01J31/069
PERFORMING OPERATIONS; TRANSPORTING
B01J13/20
PERFORMING OPERATIONS; TRANSPORTING
A61K9/0004
HUMAN NECESSITIES
B01J13/18
PERFORMING OPERATIONS; TRANSPORTING
B01J37/0217
PERFORMING OPERATIONS; TRANSPORTING
B01J2231/64
PERFORMING OPERATIONS; TRANSPORTING
International classification
B01J31/02
PERFORMING OPERATIONS; TRANSPORTING
B01J35/00
PERFORMING OPERATIONS; TRANSPORTING
B01J37/02
PERFORMING OPERATIONS; TRANSPORTING
Abstract
Disclosed are a hollow mesoporous organic silica nano/microparticle having metal particles deposited thereon, and a method for preparing the same of the present disclosure. The method may prepare a spherical nanoparticle by coating a porous organic silica layer on an inorganic silica particle having the metal particles deposited thereon and via selective etching of the layer. In addition, two or more types of metals pre-synthesized together with a magnetic particle, or different shapes of metals may be deposited on the nanoparticle at a target concentration. Thus, the nano/microparticle may be used for a drug delivery matrix, a catalyst, and a photothermal effect.
Claims
1. A method for preparing a hollow mesoporous organic silica nano/microparticle having metal particles deposited thereon, the method comprising: coating a porous organic silica layer on a surface of an inorganic silica particle having the metal particles deposited thereon; and selectively etching the inorganic silica.
2. The method of claim 1, wherein the inorganic silica particle having the metal particles deposited thereon is prepared by a method including: modifying the surface of the inorganic silica particle with a metal-affinity functional group to prepare an inorganic silica particle having the metal-affinity functional group introduced on the surface of the inorganic silica; attaching the metal particles to the metal affinity functional group to prepare an inorganic silica particle with the metal particles attached thereto; and coating an inorganic silica layer on the inorganic silica particle with the metal particles attached thereto.
3. The method of claim 2, wherein the inorganic silica particle contains magnetic nanoparticles therein.
4. The method of claim 2, wherein the metal-affinity functional group is one of an amine group and a thiol group.
5. The method of claim 2, wherein the inorganic silica is synthesized from tetraethyl orthosilicate (TEOS).
6. The method of claim 2, wherein the metal-affinity functional group is introduced from a member selected from the group consisting of (3-aminopropyl)trimethoxysilane (APTMS), (3-aminopropyl)triethoxysilane (APTES), (3-mercaptopropyl)trimethoxysilane (MPTMS) and (3 -mercaptopropyl)triethoxysilane (MPTES).
7. The method of claim 2, wherein the coating of the inorganic silica layer on the inorganic silica particle with the metal particles attached thereto includes the step of coating the inorganic silica layer to cover all of the metal particles.
8. The method of claim 1, wherein the porous organic silica layer has an open core.
9. The method of claim 1, wherein the coating of the porous organic silica layer is synthesized from solution of an organic silica precursor and a surfactant mixed with each other.
10. The method of claim 9, wherein the organic silica precursor comprises at least one member selected from the group consisting of bis(triethoxysilyl)ethane (BTSE), bis(triethoxysilyl)ethylene (BTSEY), bis-[3-(triethoxysilyl)tetrasulfide] (BTES), bis(triethoxysilyl)phenylene (BTEB), bis(triethoxysilyl)-biphenyl (BTEBP), 1,8-bis(triethoxysilyl)octane (BTEO), bis[3-(triethoxysilyl)propyl] tetrasulfide (BTEPT) and N,N′-bis-[(3-triethoxysilylpropyl)aminocarbonylpolyethylene oxide] (BTEPEO).
11. The method of claim 9, wherein the surfactant comprises at least one member selected from the group consisting of hexadecyltrimethylammonium bromide (CTAB), cetyltrimethylammonium chloride (CTAC), sodium dodecyl sulfate (SDS), polysorbates and triton.
12. The method of claim 1, wherein the selective etching is performed by heating aqueous solution containing the dispersed inorganic silica particles.
13. The method of claim 1, wherein the selective etching is performed by heating basic aqueous solution containing the dispersed inorganic silica particles.
14. The method of claim 13, wherein a basic component in the basic aqueous solution is selected from the group consisting of sodium hydroxide, potassium hydroxide, tetramethylammonium hydroxide, ammonia, sodium carbonate, sodium hydrogen carbonate, potassium carbonate and potassium hydrogen carbonate.
15. A hollow mesoporous organic silica nano/microparticle having metal particles deposited thereon prepared according to claim 1.
16. The hollow mesoporous organic silica nano/microparticle of claim 15, wherein the metal particle includes at least two types of metal particles or includes different shapes of metal particles, and wherein the at least two types of metal particles or the different shapes of metal particles are deposited thereon the hollow mesoporous organic silica nano/microparticle.
17. The hollow mesoporous organic silica nano/microparticle of claim 16, wherein the metal is gold.
18. The hollow mesoporous organic silica nano/microparticle of claim 16, wherein the metal is catalyst metal.
19. The hollow mesoporous organic silica nano/microparticle of claim 16, wherein the nano/microparticle carries a drug.
Description
BRIEF DESCRIPTION OF THE DRAWINGS
[0029]
[0030]
[0031]
[0032]
[0033]
[0034]
[0035]
[0036]
[0037]
[0038]
[0039]
[0040]
[0041]
[0042]
DETAILED DESCRIPTIONS
[0043] Hereinafter, an embodiment of the present disclosure will be described in detail with reference to the accompanying drawings. The present disclosure may be variously modified and may take many forms. Thus, specific embodiments will be illustrated in the drawings and described in detail herein. However, the specific embodiments are not intended to limit the present disclosure thereto. It should be understood that all changes, equivalents thereto, or substitutes therewith are included in a scope and spirit of the present disclosure. In describing the drawing, similar reference numerals are used for similar components.
[0044] The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the present disclosure. As used herein, the singular forms “a” and “an” are intended to include the plural forms as well, unless the context clearly indicates otherwise. It will be further understood that the terms “comprises”, “comprising”, “includes”, and “including” when used in this specification, specify the presence of the stated features, integers, operations, elements, and/or components, but do not preclude the presence or addition of one or greater other features, integers, operations, elements, components, and/or portions thereof.
[0045] Unless otherwise defined, all terms including technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this inventive concept belongs. It will be further understood that terms, such as those defined in commonly used dictionaries, should be interpreted as having a meaning that is consistent with their meaning in the context of the relevant art and will not be interpreted in an idealized or overly formal sense unless expressly so defined herein.
Method for Preparing a Hollow Mesoporous Organic Silica Nano/Microparticle Having Metal Particles Deposited Thereon
[0046] The present disclosure provides a method for preparing a hollow mesoporous organic silica nano/microparticle having metal particles deposited thereon.
[0047]
[0048] Referring to
[0049] The method for preparing the hollow mesoporous organic silica nano/microparticles having the metal particles deposited thereon includes: coating a porous organic silica layer on a surface of an inorganic silica particle having the metal particles deposited thereon; and selectively etching the inorganic silica. The inorganic silica particle having the metal particles deposited thereon may be prepared by a method including: modifying the surface of the inorganic silica particle with a metal-affinity functional group to prepare an inorganic silica particle having the metal-affinity functional group introduced on the surface of the inorganic silica; attaching the metal particles to the metal affinity functional group to prepare an inorganic silica particle to which the metal particles are attached; and coating an inorganic silica layer on the inorganic silica particle to which the metal particles are attached.
[0050] Specifically, first, the prepared inorganic silica particle is prepared. The inorganic silica particle may be synthesized from tetraethyl ortho silicate (hereinafter, TEOS). In this connection, the inorganic silica particle may contain metal oxide therein. For example, the inorganic silica particle may contain magnetic nanoparticles, and preferably, the magnetic nanoparticles may be Fe.sub.3O.sub.4. The inorganic silica particle containing the metal oxide may be prepared by coating metal oxide nanoparticles with the inorganic silica using an inorganic silica precursor TEOS.
[0051] In order to attach the metal particles to the inorganic silica particle, the surface of the inorganic silica particle is modified with the metal-affinity functional group to prepare the inorganic silica particle onto which the metal-affinity functional group is introduced. The metal-affinity functional group may be one of an amine group and a thiol group, and the metal-affinity functional group may be introduced from one selected from a group consisting of (3-aminopropyl)trimethoxysilane (hereinafter, APTMS), (3-aminopropyl)triethoxysilane (hereinafter, APTES), (3-mercaptopropyl)trimethoxysilane (hereinafter, MPTMS), (3-mercaptopropyl)triethoxysilane (hereinafter, MPTES), and the like as precursors. Preferably, when the metal-affinity functional group is the amine group, the metal-affinity functional group may be introduced from one selected from a group consisting of the (3-aminopropyl)trimethoxysilane (hereinafter, the APTMS) and the (3-aminopropyl)triethoxysilane (hereinafter, the APTES). When the metal-affinity functional group is the thiol group, the metal-affinity functional group may be introduced from one selected from a group consisting of the (3-mercaptopropyl)trimethoxysilane (hereinafter, the MPTMS) and the (3-mercaptopropyl)triethoxysilane (hereinafter, the MPTES).
[0052] The inorganic silica particle to which the metal particles are attached is prepared by attaching the metal particles to the metal-affinity functional group of the inorganic silica onto which the metal-affinity functional group is introduced. The metal particles may be two or more types of metal, or metal particles of different shapes, and the metal particles may be in a form of a nanocube, a nanorod, a nanocage, and the like. As the metal, gold (Au), silver (Au), palladium (Pd), platinum (Pt), and the like may be used. The metal particles may be stirred in aqueous ethanol solution to be attached. For example, a palladium nanocube and a gold nanoparticle may be used as the metal particle.
[0053] The inorganic silica layer is additionally coated on the inorganic silica particle to which the metal particles are attached to prepare the inorganic silica particle having the metal particles deposited thereon. In this connection, the inorganic silica layer may be coated to cover all of the metal particles of the inorganic silica particle to which the metal particles are attached. When the inorganic silica layer is coated to only cover some of the metal particles, it is difficult to prepare a hollow mesoporous organic silica nano/microparticle having spherical metal particles deposited thereon because of exposed metal particles. In addition, the exposed metal particles sink into a mesoporous layer and the shell, which is an interface, in the process of the formation of the mesoporous shell, and are not able to be freely dispersed in an inner cavity of the hollow mesoporous organic silica nano/microparticle having the finally prepared metal particles deposited thereon, so that there is a problem that it is difficult to prepare a mesoporous shell having a high porosity.
[0054] The coating of the inorganic silica layer on the inorganic silica particle to which the metal particles are attached may be essential in preparing the hollow mesoporous organic silica nano/microparticles having the metal particles deposited thereon in an independently movable manner. In addition, the inorganic silica layer may be coated through seeded growth. Further, through the above step, the hollow mesoporous organic silica nano/microparticle capable of having various types of metal particles that have already been synthesized deposited thereon may be prepared.
[0055] In one implementation, the inorganic silica layer may be synthesized from the tetraethyl orthosilicate (hereinafter, the TEOS), in the same manner as the inorganic silica particle, and the silica layer may be coated with a seeded growth technique using the TEOS as the precursor.
[0056] A porous organic silica layer is coated on the inorganic silica layer present on the inorganic silica particle having the metal particles deposited thereon. The porous organic silica layer may be synthesized from solution in which an organic silica precursor and a surfactant are mixed with each other. The surfactant is used as a material that guides formation of a meso channel. In one implementation, hexadecyltrimethylammonium bromide (hereinafter, CTAB), cetyltrimethylammonium chloride (hereinafter, CTAC), sodium dodecyl sulfate (SDS), polysorbates, triton, and the like may be used as the surfactant. The organic silica precursor may one or combinations of at least two of bis(triethoxysilyl)ethane (hereinafter, BTSE), bis(triethoxysilyl)ethylene (hereinafter, BTSEY), bis-[3 -(triethoxysilyl)tetrasulfide] (hereinafter, BTES), bis(triethoxysilyl)phenylene (hereinafter, BTEB), bis(triethoxysilyl)-biphenyl (hereinafter, BTEBP), 1,8-bis(triethoxysilyl)octane (hereinafter, BTEO), bis[3-(triethoxysilyl)propyl] tetrasulfide (hereinafter, BTEPT), N,N′-bis-[(3-triethoxysilylpropyl)aminocarbonylpolyethylene oxide] (hereinafter, BTEPEO), and the like. When the BTES, the BTEB, the BTEBP, the BTEO, the BTEPT, the BTEPEO, and the like are used as the organic silica precursor, properties of organic functional groups may be freely controlled by hybridizing various organic functional groups in a silica framework by changing only a type of the organic silica precursor without changing other synthetic protocols. Further, the porous organic silica layer may have an open core.
[0057] The step of selectively etching the inorganic silica may be included after the coating of the porous organic silica layer, thereby preparing the hollow mesoporous organic silica nanoparticle having the metal particles deposited thereon. The selective etching may be performed using hydrothermal etching.
[0058] In one implementation, the selective etching may be performed by heating aqueous solution in which the inorganic silica particles are dispersed.
[0059] In another implementation, the selective etching may be performed by heating basic aqueous solution in which the inorganic silica particles are dispersed. In the basic aqueous solution, a basic component may be selected from a group consisting of sodium hydroxide, potassium hydroxide, tetramethylammonium hydroxide, ammonia, sodium carbonate, sodium hydrogen carbonate, potassium carbonate, and potassium hydrogen carbonate.
[0060] As an example, the inorganic silica prepared using the TEOS is selectively etched using sodium carbonate aqueous solution as the basic aqueous solution based on a difference in a structure of the inorganic silica prepared using the TEOS, which is the inorganic silica precursor, and the porous organic silica layer formed by the CTAB and the BTSE. In addition, the CTAB, which is a meso channel guide material, is removed through ion exchange using ammonium nitrate in the ethanol solution. Thus, the hollow mesoporous organic silica nano/microparticle having the magnetic nanoparticles and/or the metal particles deposited thereon may be finally prepared.
Hollow Mesoporous Organic Silica Nano/Microparticle Having Different Types or Different Shapes of Metal Particles Simultaneously Deposited Thereon
[0061] The hollow mesoporous organic silica nanoparticle having the metal particles deposited thereon of the present disclosure may be prepared by the method for preparing the hollow mesoporous organic silica nanoparticle having the metal particles deposited thereon of the present disclosure.
[0062] In the hollow mesoporous organic silica nano/microparticle having the metal particles deposited thereon, the metal may be the two or more types of metal, or the metal particles of the different shapes. The hollow mesoporous organic silica nano/microparticles having the metal particles deposited thereon may have the two or more different types of metal, or two or more different shapes of metal deposited thereon. For example, the metal particle may be in the form of the nanocube, the nanorod, the nanocage, and the like. As the metal, the gold (Au), the silver (Au), the palladium (Pd), the platinum (Pt), and the like may be used.
[0063] The hollow mesoporous organic silica nano/microparticle having the metal particles deposited thereon of the present disclosure may have not only a narrow size distribution and a high magnetic level, but also the meso channel present in the mesoporous organic silica layer and the hollow inner space. Further, the type of the metal particles may be freely tuned, and the metal particles may be deposited while adjusting a concentration of the metal particles.
[0064] The hollow mesoporous organic silica nano/microparticles having the metal particles deposited thereon of the present disclosure having the metal particles and the mesoporous organic silica shell has a wide range of applications such as catalysis, energy storage, and nano medicine.
[0065] In one implementation, in the hollow mesoporous organic silica nano/microparticle having the metal particles deposited thereon, the nano/microparticle may carry drug, and the nano/microparticle may be used as a drug carrier. In one implementation, when the metal is the gold in the hollow mesoporous organic silica nano/microparticle having the metal particles deposited thereon, the nano/microparticle may be used for photothermal therapy. In one implementation, when the metal is catalyst metal in the hollow mesoporous organic silica nano/microparticle having the metal particles deposited thereon, the nano/microparticle may be used as the catalyst.
[0066] Hereinafter, the hollow mesoporous organic silica nano/microparticles having the metal particles deposited thereon and the method for preparing the same of the present disclosure will be described in more detail with specific implementations.
EXAMPLE 1
[0067] (1) Synthesis of Fe.sub.3O.sub.4@SiO.sub.2—NH.sub.2@AuNP
[0068] A core-shell Fe.sub.3O.sub.4@SiO.sub.2 composite was prepared using the Stober method. First, ethanol dispersion (35 mL, 1.15 mg/mL) in which Fe.sub.3O.sub.4 is dispersed was put into a 50 mL self-standing falcon tube containing a mixture of 2.5 mL of deionized water and 3 mL of ammonia solution. Thereafter, 4 mL of ethanol solution in which 40 vol % of Tetraethyl orthosilicate (hereinafter, the TEOS) is present was rapidly injected into the mixture, and the mixture was reacted at room temperature for 1 hour while rotating at a speed of 10 rpm. Subsequently, the obtained Fe.sub.3O.sub.4@SiO.sub.2 was filtered and collected, washed several times with the ethanol and the deionized water, and redispersed into 500 mL of deionized water. In order to functionalize a surface of the redispersed Fe.sub.3O.sub.4@SiO.sub.2 with an amino group, (3-aminopropyl)trimethoxysilane (hereinafter, APTMS) (25 mL, 10 vol %) and 5 mL of ammonia solution were added into 500 mL of the Fe.sub.3O.sub.4@ SiO.sub.2 solution, and mechanically stirred at 40° C. for 12 hours to be reacted. Subsequently, Fe.sub.3O.sub.4@SiO.sub.2—NH.sub.2 to which the amino group functional group is attached was collected by filtration, washed several times with the ethanol and the deionized water, and re-dispersed again in 40 mL of deionized water. In order to decorate a surface of the Fe.sub.3O.sub.4@SiO.sub.2—NH.sub.2 with AuNP (Au Nano-Particles), after adding aqueous dispersion of AuNP (1 mL, 600 μg/mL) to 5 mL of the Fe.sub.3O.sub.4@SiO.sub.2—NH.sub.2 solution, the mixture was sonicated for 30 minutes and then vigorously stirred for 3 hours to obtain a product. Subsequently, the obtained product was collected by filtration, washed several times with the ethanol and the deionized water, and re-dispersed in 32.5 mL of 1-propanol for a next synthesis procedure, thereby obtaining Fe.sub.3O.sub.4@ SiO.sub.2—NH.sub.2@ AuNP, which is an inorganic silica particle to which a gold particle is attached.
(2) Synthesis of Fe.sub.3O.sub.4@SiO.sub.2—NH.sub.2@AuNP@SiO.sub.2
[0069] Using a seeded silica growth method, the inorganic silica layer was coated on the Fe.sub.3O.sub.4@SiO.sub.2—NH.sub.2@AuNP to prepare Fe.sub.3O.sub.4@SiO.sub.2—NH.sub.2@AuNP@SiO.sub.2. Specifically, 32.5 mL of the obtained Fe.sub.3O.sub.4@SiO.sub.2—NH.sub.2@AuNP solution was added into the 50 mL self-standing falcon tube containing the mixture of 2.5 mL of deionized water and 3 mL of ammonia solution. Thereafter, a 0.5 mL solution of 1-propanol in which 20 vol % of TEOS is present was rapidly injected into the mixture, and the mixture was reacted at room temperature for 1 hour while rotating at a speed of 10 rpm to obtain a product. Then, the obtained product was collected by filtration, washed several times with the methanol and the deionized water, and re-dispersed in 20 mL solution in which methanol and aqueous solution exist in 3:7 for a next synthesis procedure, thereby obtaining Fe.sub.3O.sub.4@SiO.sub.2—NH.sub.2@AuNP@SiO.sub.2.
(3) Synthesis of Fe.sub.3O.sub.4@SiO.sub.2—NH.sub.2@AuNP@SiO.sub.2.
[0070] The porous organic silica layer was coated on the Fe.sub.3O.sub.4@SiO.sub.2—NH.sub.2@AuNP@SiO.sub.2. Specifically, mixed solution was prepared by mixing 20 mL of the Fe.sub.3O.sub.4@SiO.sub.2. NH.sub.2@AuNP@SiO.sub.2 solution into a 50 mL self-standing falcon tube containing a mixture of 1.4 mL of methanol, 56 mg of CTAB, and 1 mL of ammonia solution. 0.3 mL of methanol solution in which 5 vol % of BTSE is present was rapidly injected into the mixed solution, and reacted at room temperature for 2 hours while rotating at a speed of 10 rpm. Then, the obtained product was collected by filtration, washed several times with the methanol and the deionized water, and re-dispersed in 20 mL of deionized water to obtain Fe.sub.3O.sub.4@SiO.sub.2—NH.sub.2@AuNP@SiO.sub.2@mSiO.sub.2, which is an inorganic silica particle having metal particles coated with the porous organic silica layer deposited thereon.
(4) Synthesis of Fe.sub.3O.sub.4/AuNP@YMOM
[0071] In order to selectively etch non-porous inorganic silica present inside the inorganic silica particle having the metal particles coated with the porous organic silica layer deposited thereon, 20 mL of the solution of Fe.sub.3O.sub.4@SiO.sub.2—NH.sub.2@AuNP@SiO.sub.2@mSiO.sub.2 obtained above was heated up to 80° C. while being mechanically stirred, then Na.sub.2CO.sub.3 (3 mL, 40 mg/mL), which is basic aqueous solution, was added into 20 mL of the solution of Fe.sub.3O.sub.4@ SiO.sub.2. NH.sub.2@ AuNP@ SiO.sub.2 @ mSiO.sub.2 to form a mixture, and then the mixture is selectively etched. After 1 hour of the etching, a product was obtained. The product was collected by magnet and washed several times with the deionized water. The CTAB, which is the surfactant, was extracted by rapid ion exchange, and treated in ethanol solution (20 mL, 6 mg/mL) in which the ammonium nitrate is present for 3 hours at 60 ° C. Further, in order to completely remove the CTAB, the above process was repeated twice to obtain a surfactant-free product. Finally, the surfactant-free product was collected by the magnet, washed several times with the deionized water, and dried at room temperature for later use, so that the hollow mesoporous organic silica nanoparticle having the metal particles deposited thereon according to example 1 of the present disclosure was finally obtained. The obtained hollow mesoporous organic silica nano/microparticles having the metal particles deposited thereon was referred to as Fe.sub.3O.sub.4/AuNP@YMOM.
[Property Analysis]
[0072] Analysis on structural properties, structural morphology, and properties of the Fe.sub.3O.sub.4/AuNP@YMOM, which is the hollow mesoporous organic silica nano/microparticles having the metal particles deposited thereon prepared according to Example 1, was performed.
(1) Scanning Electron Microscope Scanning Electron Microscope (SEM) Analysis
[0073] Morphology analysis of the Fe.sub.3O.sub.4/AuNP@YMOM prepared according to Example 1 was performed by a FE-SEM (SUPRA 25, EDAX, carl Zeiss Co, Germany).
[0074]
[0075] Referring to
(2) Field-Emission Transmission Electron Microscopy (FE-TEM) Analysis
[0076] Using a FE-TEM (TALOS F200X, Thermofisher Scientific Co, USA) combined with energy dispersive spectrometry (an energy-dispersive X-RAY, EDX), structural and qualitative elemental analysis on the Fe.sub.3O.sub.4/AuNP@YMOM prepared according to Example 1 was performed. A result of the structural and qualitative element analysis is shown in
[0077]
[0078] First, Referring to a) in
[0079] Referring to b) in
[0080] Referring to c) in
(3) X-ray Diffractometry (XRD)
[0081] In order to analyze a crystal phase of the Fe.sub.3O.sub.4/AuNP@YMOM prepared according to Example 1 of the present disclosure, x-ray diffractometry was performed using an x-ray diffractometer (an xpert3 diffractometer, Malvern Panalytical Ltd, UK) through Cu Kα radiation at 40 kV and 40 mA. A result thereof is shown in
[0082]
[0083] Referring to
(4) Nitrogen Sorption and Pore Size Analysis
[0084] In order to analyze nitrogen sorption and a pore size of the Fe.sub.3O.sub.4/AuNP@YMOM prepared according to Example 1 of the present disclosure, a description will be made with reference to
[0085]
[0086] In
(5) Magnetic Property Analysis
[0087] A magnetic property of the Fe.sub.3O.sub.4/AuNP@YMOM prepared according to Example 1 of the present disclosure will be described with reference to
[0088]
[0089] a) in
(6) Photothermal Conversion
[0090] In order to quantitatively evaluate a concentration of the AuNP deposited on the Fe.sub.3O.sub.4/AuNP@YMOM prepared according to Example 1 of the present disclosure, a photothermal conversion efficiency of the Fe.sub.3O.sub.4/AuNP@YMOM aqueous suspension was measured under 635 nm laser irradiation. The Fe.sub.3O.sub.4/AuNP@YMOM aqueous suspension of a specific concentration was placed in a 200 μL microcentrifuge tube and irradiated with a 635 nm laser for 200 seconds at an output density of 0.55 W/cm.sup.2. A temperature change and an IR image of the sample during the laser irradiation were recorded every 10 seconds using an infrared thermal imaging system (FLIR C3, FLIR Systems Inc, Korea), and a result thereof is shown in
[0091]
[0092] Referring to
(7) Catalytic Reaction
[0093] In order to identify a catalytic reaction,
[0094]
[0095] A hollow mesoporous organic silica nanoparticle having the palladium metal particles deposited thereon Fe.sub.3O.sub.4/PdNP@YMOM was prepared using a method substantially the same as the preparation method in Example 1 except for using 4 w % of Pd palladium particles as the metal particles.
[0096] Further, Fe.sub.3O.sub.4@SiO.sub.2—NH.sub.2@PdNP@SiO.sub.2@mSiO.sub.2, which is a comparative sample, was prepared using a method substantially the same as the preparation method of the Fe.sub.3O.sub.4/PdNP@YMOM except for the step of the selective etching.
[0097] Further, Fe.sub.3O.sub.4@SiO.sub.2—NH.sub.2@PdNP, which is a comparative sample, was prepared using a process substantially the same as the preparation method of the Fe.sub.3O.sub.4@SiO.sub.2—NH.sub.2@PdNP@SiO.sub.2@mSiO.sub.2 except for a step of coating a silica layer on a metal-attached silicon particle and coating a porous organic silica layer on the silica layer.
[0098] a) in
[0099] For the prepared Fe.sub.3O.sub.4/PdNP@YMOM, the Fe.sub.3O.sub.4@SiO.sub.2—NH.sub.2@PdNP, and the Fe.sub.3O.sub.4@SiO.sub.2—NH.sub.2@PdNP@SiO.sub.2@mSiO.sub.2, the catalytic reactions were performed as follows. An aqueous dispersion of the Fe.sub.3O.sub.4/PdNP@YMOMs (10 mL, 10 m/mL) was added to a 50 mL self-standing falcon tube containing NaBH.sub.4 aqueous solution (10 mL, 0.05 M). Then, 4-nitrophenol (hereinafter, 4-NP) aqueous solution (140 μL, 0.01 M) was added thereto and reacted immediately. A UV-vis spectroscopy was used to monitor a change in absorption during the reaction. For comparative studies, the same process was repeated for the Fe.sub.3O.sub.4@SiO.sub.2—NH.sub.2@PdNP and the Fe.sub.3O.sub.4@SiO.sub.2—NH.sub.2@PdNP@SiO.sub.2@mSiO.sub.2, and a result thereof is shown in b) and c) in
[0100] Referring to b) in
[0101] It may be expected that an excellent catalytic performance of the Fe.sub.3O.sub.4/PdNP@YMOMs compared to the Fe.sub.3O.sub.4@SiO.sub.2—NH.sub.2@PdNP is mainly due to the Pd palladium particles well dispersed independently in the hollow space. Thus, it may be seen that the Fe.sub.3O.sub.4/PdNP@YMOMs has a high catalytic reaction rate because the Fe.sub.3O.sub.4/PdNP@YMOMs has a much higher catalytic activity surface area. Such result reflects that the uniform vertical meso channels of the organic silica layer facilitate high-rate diffusion and transport of the reactant and the product molecule.
[Comparative Analysis]
[0102] For comparative analysis, Sample-1 of a hollow mesoporous organic silica nanoparticle having the Au and the Fe.sub.3O.sub.4 deposited thereon prepared by the method for preparing the hollow mesoporous organic silica nanoparticle having the metal particles deposited thereon of the present disclosure was prepared.
[0103]
[0104] a) in
[0105] Referring to a) in
[0106] Further, in order to compare with this, Comparative Sample-1 of the hollow mesoporous organic silica nanoparticle having the Au and the Fe.sub.3O.sub.4 deposited thereon was prepared. A method for preparing Comparative Sample-1 will be described with reference to b) in
[0107] b) in
[0108] Referring to b) in
[0109] For comparative analysis of Sample-1 and Comparative Sample-1 nanoparticles prepared using different methods, each of which was analyzed using a transmission electron microscopy (TEM). a result thereof is shown in
[0110]
[0111] When comparing Sample-1 and Comparative Sample-1 with each other with reference to
[0112] The difference between the nanoparticles prepared using the preparation methods of Sample-1 and Comparative Sample-1 as described above is very important in two aspects. First, when the inorganic nanoparticle used as the catalysts is deposited on the nanoparticle, in the case of the preparation without the coating of the inorganic silica layer for covering the metal as in the preparation method of Comparative Sample-1, because the inorganic nanoparticle sinks and is buried into and present in the mesoporous organic silica layer, a contact area with the reactant is lowered, so that a catalytic activity may be deteriorated or a function as the catalyst may be lost. Second, in the case of the preparation as in the preparation method of Comparative Sample-1, there is a problem that a space in which the inorganic nanoparticle is deposited is limited to an inner surface of the inner cavity. The nanoparticle prepared using the preparation method of the present disclosure has an advantage of dramatically increasing an absolute amount of catalyst that may be deposited because an entirety of the inner cavity becomes a space in which the catalyst may be dispersed.
[Application]
(1) Hollow Mesoporous Organic Silica Nanoparticle Having Various Shapes and Various Types of Metal Particles Deposited Thereon
[0113] In order to identify that the metal is the two or more types of metal or the metal particles of different shapes, and that the at least two different types of metal or the at least two different shapes of metal may be deposited on the hollow mesoporous organic silica nanoparticle having the metal particles deposited thereon prepared according to the present disclosure, a description will be made with reference to
[0114]
[0115] Referring to
[0116] d) in
[0117] e) in
[0118] It may be expected from
[0119] Further, it was identified that two or more types of metal nanoparticles with different shapes and components may be deposited on the mesoporous layer. Thus, it may be expected that the present disclosure has a very high applicability to a medical field by introducing additional metal nanoparticles capable of performing various functions such as a biocatalytic reaction, an MRI, and the like by depositing not only the gold nanoparticle, but also a metal nanoparticles having a completely different function. Further, the mesoporous organic silica nanoparticle having such metal particles deposited thereon has great significance in enabling complex functions to be implemented in the single nanoparticle structure.
(2) Hollow Mesoporous Organic Silica Nanoparticle Having Metal Particles of an Adjusted Concentration
[0120] In order to identify that the metal particles may be deposited while varying the concentration thereof based on the preparation according to the method for preparing the hollow mesoporous organic silica nanoparticle having the metal particles deposited thereon of the present disclosure, a description will be made with reference to
[0121]
[0122] Referring to
(3) Application of Drug Releasing Material
[0123] In addition to the fact that the hollow mesoporous organic silica nanoparticle having the metal particles deposited thereon of the present disclosure may have various inorganic nanoparticles deposited inside the hollow, because an oil material may be post-encapsulated through the mesoporous organic silica layer, the hollow mesoporous organic silica nanoparticle having the metal particles deposited thereon of the present disclosure may be applied as a photo-stimulative drug releasing material of micron to submicron size by combining a photothermal effect of the metal particles and a phase change function based on a temperature of a phase change material (hereinafter, PCM) with each other.
[0124]
[0125] Referring to b in
(4) Utilization of Tandem Micro Reactor
[0126] A fact that the hollow mesoporous organic silica nanoparticle having the metal particles deposited thereon prepared according to the present disclosure may be utilized as a micro reactor in which heterogeneous inorganic catalysts are encapsulated will be described with a specific approach through
[0127]
[0128] Referring to
[0129] The present disclosure has been described with reference to the preferred embodiments of the present disclosure. Those skilled in the art will understand that the present disclosure may be variously modified and changed without departing from the spirit and scope of the present disclosure as described in the following claims.