Nanoporous glass with controllable magnetic pore size, preparation method and application thereof

Abstract

The present invention belongs to the technical field of material preparation and processing, and in particular, relates to a magnetic pore-controllable nanoporous glass, a preparation method and an application. The present invention provides a magnetic pore-controllable nanoporous glass, a preparation method and an application, wherein the magnetic pore-controllable nanoporous glass is mainly made of silicon dioxide, boric acid, sodium carbonate, ferric oxide and zirconium oxide as raw materials; in terms of mass percentage, the raw materials include: 55% to 65% silicon dioxide, 20% to 30% boric acid, 6% to 7% sodium carbonate, 5% to 10% ferric oxide and 2% to 5% zirconium oxide. Through the magnetic pore-controllable nanoporous glass, the preparation method and the application provided by the present invention, the magnetic pore-controllable nanoporous glass prepared at a phase separation temperature of 550°C to 650°C has excellent corrosion resistance and mechanical strength, uniform pore size and pore size distribution, and high porosity; at the same time, it is stable superparamagnetic, maintains monodispersity in the absence of an external magnetic field, and can meet the performance requirements of gene synthesis carrier materials.

Description

Technical Field

[0001] The invention belongs to the technical field of material preparation and processing, and in particular relates to a nanoporous glass with controllable magnetic pore size, a preparation method and an application thereof. Background Art

[0002] Oligonucleotides are basic tools for regulating gene expression in biomedical and life science research. They can be developed into gene-targeted therapeutic drugs for the treatment of viruses, tumors and genetic diseases. With the rapid development of biotechnology, the research on oligonucleotide drugs has continued to deepen. Oligonucleotide drugs can reduce the body's tolerance to drugs, improve the utilization rate of drugs, effectively eliminate the toxic side effects of drugs, and treat viruses, tumors and genetic diseases from the source.

[0003] Controlled Pore Glass (CPG) is a carrier material for synthesizing oligonucleotides. In oligonucleotide synthesis, CPG is widely used as an inorganic solid phase carrier due to its excellent synthesis effect and stability.

[0004] In the preparation of magnetic CPG from sodium borosilicate and iron oxide component glass, the melted glass is subjected to phase separation treatment to form magnetic microcrystals in the glassy matrix, which significantly enhances its magnetism and forms magnetic CPG. Magnetic CPG can be used in gene synthesis and purification, and gene separation is achieved through magnetic adsorption. Compared with centrifugal separation, this method of separation using magnetic adsorption is obviously more convenient. Therefore, magnetic CPG, as a solid phase carrier of biological materials, has great potential use in the field of gene synthesis.

[0005] In the prior art, the corrosion resistance of magnetic CPG prepared from sodium borosilicate and iron oxide component glass is generally insufficient. For example, the prepared magnetic CPG is easily corroded during gene synthesis and biological separation processes; it cannot maintain monodispersity well, and the pore size and pore size distribution range are large, the mechanical strength difference is also large, and there are even defects such as severe pore blockage and low porosity, which seriously restricts its application as an oligonucleotide carrier material.

[0006] In practical applications, magnetic CPG needs to be fully collected when an external magnetic field is applied and be in a dispersed state when there is no external magnetic field, that is, the magnetic CPG needs to have relatively stable superparamagnetism; however, in the prior art, most magnetic CPGs will aggregate even when no external magnetic field is applied, which is not conducive to their application in gene synthesis processes and biological separation processes.

[0007] In view of the above, it is urgent to design a new magnetic CPG to meet the application requirements of gene synthesis carrier materials. Summary of the invention

[0008] In view of the above, the present invention provides a magnetic pore controllable nanoporous glass, a preparation method and an application, aiming to solve the problems in the prior art that magnetic CPG cannot maintain stable superparamagnetism, has poor corrosion resistance, a large pore size and pore size distribution range, poor mechanical strength, severe pore blockage and low porosity, resulting in poor application effect as an oligonucleotide carrier material.

[0009] The first aspect of the present invention provides a nanoporous glass with controllable magnetic pore size, wherein the nanoporous glass with controllable magnetic pore size is mainly made of silicon dioxide, boric acid, sodium carbonate, ferric oxide and zirconium oxide as raw materials;

[0010] Calculated by mass percentage, the raw materials include: 55% to 65% silicon dioxide, 20% to 30% boric acid, 6% to 7% sodium carbonate, 5% to 10% ferric oxide and 2% to 5% zirconium oxide.

[0011] In the optional scheme of the present invention, the magnetic pore size controllable nanoporous glass (magnetic CPG) is mainly made of silicon dioxide, boric acid, sodium carbonate, ferric oxide and zirconium oxide as raw materials; wherein silicon dioxide accounts for 55% to 65% of the total mass of the raw materials, and the content of silicon dioxide affects the porous structure and rigidity change of the magnetic CPG. When the silicon dioxide component is less than 55%, the formed magnetic CPG porous structure is very easy to break, and when the silicon dioxide component is higher than 65%, the porous structure cannot be formed; boric acid accounts for 20% to 30% of the total mass of the raw materials, and the content of boric acid affects the porosity and specific surface area of ​​the magnetic CPG. When the boric acid content is greater than 30% or less than 20%, the porosity and specific surface area of ​​the magnetic CPG are low, which is not conducive to the application of the magnetic CPG in gene synthesis; sodium carbonate accounts for 6% to 7% of the total mass of the raw materials, and the content of sodium carbonate affects the formation of the porous structure. When the silicon dioxide is 55% to 65%, sodium carbonate less than 6% or greater than 7% cannot form an effective porous structure for the magnetic CPG; Ferrous oxide accounts for 5% to 10% of the total mass of the raw materials. The content of ferric oxide affects the magnetism of magnetic CPG. When ferric oxide is less than 5%, the magnetic CPG formed has weak magnetism. When ferric oxide is higher than 10%, the magnetic CPG formed does not have superparamagnetism, which affects the formation of pore size. Zirconia accounts for 2% to 5% of the total mass of the raw materials. An appropriate amount of zirconium oxide is beneficial to improving the corrosion resistance and rigidity of magnetic CPG. When zirconium oxide is less than 2%, the corrosion resistance and rigidity of the magnetic CPG formed are relatively When the content of zirconium oxide is higher than 5%, the formation of pore size is affected; as mentioned above, when the raw material ratio is 55% to 65% silicon dioxide, 20% to 30% boric acid, 6% to 7% sodium carbonate, 5% to 10% ferric oxide and 2% to 5% zirconium oxide, the obtained magnetic CPG has excellent mechanical strength and corrosion resistance, uniform pore size and pore size distribution, high porosity, stable superparamagnetism, and monodispersity in the absence of an external magnetic field, which can meet the application requirements of gene synthesis.

[0012] Furthermore, the density of the nanoporous glass with controllable magnetic pore size is 0.25 g / ml to 0.35 g / ml.

[0013] Furthermore, when the porosity of the magnetic pore-controllable nanoporous glass is 76% to 94% and / or the magnetic strength of the magnetic pore-controllable nanoporous glass is 12emu / g to 32emu / g and the magnetization strength of the magnetic CPG exceeds 20emu / g, a faster separation effect can be achieved in gene synthesis.

[0014] Furthermore, the magnetic pore-controllable nanoporous glass includes at least one hydroxyl group for bonding a linker in gene synthesis.

[0015] The second aspect of the present invention provides a method for preparing nanoporous glass with controllable magnetic pore size, the preparation method comprising:

[0016] S1. Mix silicon dioxide, boric acid, sodium carbonate, ferric oxide and zirconium oxide and perform ball milling to obtain a mixed sample;

[0017] S2, melting the mixed sample to obtain a melted sample;

[0018] S3, performing phase separation treatment on the melted sample at a temperature of 550°C to 650°C to obtain an intermediate;

[0019] S4. Post-treating the intermediate to obtain nanoporous glass with controllable magnetic pore size.

[0020] Furthermore, the post-treatment of the intermediate is acid-base washing of the intermediate.

[0021] Furthermore, the acid-base washing treatment of the intermediate includes: performing an acid-base washing treatment after crushing the intermediate; and performing a drying treatment after the acid-base washing treatment of the intermediate.

[0022] Furthermore, in the crushing treatment, the intermediate is crushed to 100-200 mesh; in the acid-base washing treatment, the intermediate is washed in an acid solution and an alkaline solution, and then washed with water to neutrality; in the drying treatment, the drying temperature is 120°C-160°C, and the time is 10h-14h.

[0023] Furthermore, the rotation speed of the ball milling treatment is 450-550 rpm, and the time is 20-40 min; the mixed sample is melt-treated, and the temperature of the melting treatment is 1400° C.-1500° C.

[0024] The third aspect of the present invention provides the use of the above-mentioned nanoporous glass with controllable magnetic pore size as a carrier for oligonucleotide synthesis.

[0025] The invention provides a nanoporous glass with controllable magnetic pore size, a preparation method and application thereof, which have the following beneficial effects:

[0026] The present invention designs raw material components of magnetic CPG, which include silicon dioxide, boric acid, sodium carbonate, ferric oxide and zirconium oxide. In terms of mass percentage, 55% to 65% of silicon dioxide and 6% to 7% of sodium carbonate can effectively form a porous structure of the magnetic CPG; 55% to 65% of silicon dioxide and 2% to 5% of zirconium oxide can improve the mechanical strength of the porous structure of the magnetic CPG; 20% to 30% of boric acid and 2% to 5% of zirconium oxide can improve the porosity and specific surface area of ​​the magnetic CPG, thereby increasing the effective sites when used as a gene synthesis carrier; 5% to 10% of ferric oxide can make the magnetic CPG have stable superparamagnetism; among the above components, 2% to 5% of zirconium oxide can also improve the corrosion resistance of the magnetic CPG, so that the magnetic CPG is not easy to be corroded.

[0027] The magnetic CPG prepared by the above components has excellent corrosion resistance and mechanical strength, uniform pore size and pore size distribution, and high porosity; at the same time, it exhibits stable superparamagnetism and maintains monodispersity in the absence of an external magnetic field, which can meet the performance requirements of gene synthesis carrier materials.

[0028] Other advantages and features of the present invention will be further described in the specific implementation manner. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] In order to more clearly illustrate the specific implementation methods of the present invention or the technical solutions in the prior art, the drawings required for use in the specific implementation methods or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are some implementation methods of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0030] Figure 1 This is the pore size distribution diagram of the magnetic CPG sample 1 obtained in Example 1 of the present invention;

[0031] Figure 2 This is the pore size distribution diagram of the magnetic CPG sample 2 obtained in Example 2 of the present invention;

[0032] Figure 3 This is the pore size distribution diagram of the magnetic CPG sample 3 obtained in Example 3 of the present invention;

[0033] Figure 4 This is a 500 μm scale scanning electron microscope image of the magnetic CPG sample 1 obtained in Example 1 of the present invention;

[0034] Figure 5 This is a 500nm scale scanning electron microscope image of the magnetic CPG sample 1 obtained in Example 1 of the present invention;

[0035] Figure 6 This is a 200nm scale scanning electron microscope image of the magnetic CPG sample 6 obtained in Comparative Example 1 of the present invention;

[0036] Figure 7 This is a 2 μm scale scanning electron microscope image of the magnetic CPG sample 7 obtained in Comparative Example 2 of the present invention;

[0037] Figure 8 This is a 5 μm scale scanning electron microscope image of a magnetic CPG sample 10 obtained in Comparative Example 5 of the present invention;

[0038] Fig. 9 The present invention is exemplified by the application of magnetic CPG in the process of directional purification of poly(dT)20 from poly(dA)20 in oligonucleotide synthesis. DETAILED DESCRIPTION

[0039] In order to make the above and other features and advantages of the present invention more clear, the present invention is further described below in conjunction with the accompanying drawings. It should be understood that the specific embodiments given herein are for the purpose of explaining to those skilled in the art and are only exemplary and not restrictive.

[0040] [Overall Inventive Concept]

[0041] The overall inventive concept of the present invention provides a magnetic pore-controllable nanoporous glass, a preparation method and an application thereof. In view of the performance defects of the magnetic CPG in the aforementioned prior art, the raw material components of the magnetic CPG are designed. The magnetic CPG is mainly made of silicon dioxide, boric acid, sodium carbonate, ferric oxide and zirconium oxide as raw materials; in terms of mass percentage, the raw materials include: 55% to 65% silicon dioxide, 20% to 30% boric acid, 6% to 7% sodium carbonate, 5% to 10% ferric oxide and 2% to 5% zirconium oxide.

[0042] Among the raw materials of magnetic CPG mentioned above, silicon dioxide, as the base material of magnetic CPG material, affects the formation of porous structure and the strength of porous structure. When the components are fixed, the increase of silicon content will cause the decrease of pore size, and the decrease of silicon content will cause the increase of pore size. When silicon dioxide is 55% to 65%, the introduction of 6% to 7% of sodium carbonate can make the magnetic CPG effectively form a porous structure. In view of the defects of mechanical strength and corrosion resistance of magnetic CPG in the prior art, the introduction of 2% to 5% of zirconium oxide can improve the corrosion resistance and mechanical strength of magnetic CPG, making magnetic CPG not easy to erode. 20% to 30% of boric acid and 2% to 5% of zirconium oxide can improve the porosity and specific surface area of ​​magnetic CPG. By introducing 5% to 10% of ferric oxide into the raw materials, the prepared magnetic CPG can have superparamagnetism.

[0043] Different from the existing technology, the magnetic CPG prepared by the above raw material ratio has a density of 0.25g / ml~0.35g / ml, a porosity of 76%~94%, a magnetic strength of 12emu / g~32emu / g, excellent corrosion resistance and mechanical strength, uniform pore size and pore size distribution, and high porosity; at the same time, it has stable superparamagnetism and maintains monodispersity in the absence of an external magnetic field, which can meet the performance requirements of gene synthesis carrier materials.

[0044] "Superparamagnetism" refers to a ferromagnetic material with a single domain structure when the particles are smaller than the critical size. It exhibits paramagnetic characteristics when the temperature is lower than the Curie temperature and higher than the transition temperature (Block Temperature). However, under the action of an external magnetic field, its paramagnetic susceptibility is much higher than that of general paramagnetic materials. Materials in the superparamagnetic state have two characteristics: no hysteresis loop and zero coercive force.

[0045] As mentioned above, the size of the magnetic CPG material is an important factor affecting whether the magnetic CPG is in a superparamagnetic state, so superparamagnetism has a strong size effect, and superparamagnetism is also related to time and temperature. Therefore, based on the above general inventive concept, a preparation method of magnetic CPG is designed.

[0046] In the general inventive concept, the preparation process comprises the following steps:

[0047] S1. Mix silicon dioxide, boric acid, sodium carbonate, ferric oxide and zirconium oxide and perform ball milling to obtain a mixed sample;

[0048] S2, melting the mixed sample to obtain a melted sample;

[0049] S3, performing phase separation treatment on the melted sample at a temperature of 550°C to 650°C to obtain an intermediate;

[0050] S4. Post-treating the intermediate to obtain nanoporous glass with controllable magnetic pore size.

[0051] Among them, the ball milling treatment can be carried out by using a ball mill at a speed of 450 to 550 rpm for 20 to 40 minutes to obtain a mixed sample; the temperature of the melting treatment is controlled in the range of 1400°C to 1500°C; the intermediate is post-treated by crushing the intermediate to 100 to 200 meshes, performing acid and alkali washing in an acid and alkali solution, and then washing with water to neutrality, and drying at a temperature of 120°C to 160°C for 10h to 14h.

[0052] In the above preparation method, the phase separation temperature plays a decisive role in the pore size and superparamagnetism of the magnetic CPG. When the phase separation treatment is carried out at a phase separation temperature lower than 550°C, the magnetic strength of the obtained magnetic CPG is weak and the pore size is broken. When the phase separation treatment is carried out at a phase separation temperature higher than 650°C, the residual coercive force of the obtained magnetic CPG is too much, showing non-superparamagnetic properties.

[0053] The magnetic CPG prepared by the preparation method is used as a solid phase synthesis carrier in gene synthesis, which can well meet the application requirements of synthesizing gene fragments such as oligonucleotides. The magnetic CPG of the present invention can be used as a solid phase synthesis carrier to synthesize oligonucleotides by a DNA synthesis device. The linker is bonded to the hydroxyl group of the magnetic CPG particles of the present invention, and then the phosphoramidite units are gradually bonded to obtain a predetermined base sequence starting from the end of the linker.

[0054] The following is described by specific embodiments:

[0055] [Example 1]

[0056] Weigh 60g of silicon dioxide, 25g of boric acid, 7g of anhydrous sodium carbonate, 6g of ferric oxide, and 2g of zirconium oxide and place them in a 500ml corundum ball mill, and perform ball milling at 500 rpm for 30min; then place the ball-milled sample in a corundum crucible and perform melting treatment at 1450 degrees for 12h; then perform phase separation treatment at 610 degrees for 24h; crush the intermediate after phase separation into 100-200 mesh, then wash it in 0.5mol / l hydrochloric acid at 98 degrees for 24h, perform alkaline washing in 2mol / l sodium hydroxide solution at 40 degrees for 4h, wash it with water until neutral, and dry it at 140 degrees for 12h to obtain magnetic CPG sample 1.

[0057] [Example 2]

[0058] Weigh 55g of silicon dioxide, 30g of boric acid, 7g of anhydrous sodium carbonate, 6g of ferric oxide, and 2g of zirconium oxide and place them in a 500ml corundum ball mill, and perform ball milling at 500 rpm for 30min; then place the ball-milled sample in a corundum crucible and perform melting treatment at 1450 degrees for 12h; then perform phase separation treatment at 580 degrees for 24h, crush the intermediate after phase separation into 100-200 mesh, then wash in 0.5mol / l hydrochloric acid at 98 degrees for 24h, perform alkaline washing in 2mol / l sodium hydroxide solution at 40 degrees for 4h, wash with water until neutral, and dry at 140 degrees for 12h to obtain magnetic CPG sample 2.

[0059] Compared with Example 1, the silicon dioxide component content in Example 2 is lower, the boric acid component content is higher, and the phase separation temperature is lower.

[0060] [Example 3]

[0061] Weigh 65g of silicon dioxide, 20g of boric acid, 7g of anhydrous sodium carbonate, 6g of ferric oxide, and 2g of zirconium oxide and place them in a 500ml corundum ball mill, and perform ball milling at 500 rpm for 30min; then place the ball-milled sample in a corundum crucible and perform melting treatment at 1450 degrees for 12h; then perform phase separation treatment at 635 degrees for 24h, crush the intermediate after phase separation into 100-200 mesh, then wash in 0.5mol / l hydrochloric acid at 98 degrees for 24h, perform alkaline washing in 2mol / l sodium hydroxide solution at 40 degrees for 4h, wash with water until neutral, and dry at 140 degrees for 12h to obtain magnetic CPG sample 3.

[0062] Compared with Example 1, the silicon dioxide component content in Example 3 is higher, the boric acid component content is lower, and the phase separation temperature is higher.

[0063] [Example 4]

[0064] Weigh 60g of silicon dioxide, 25g of boric acid, 7g of anhydrous sodium carbonate, 5g of ferric oxide, and 3g of zirconium oxide and place them in a 500ml corundum ball mill, and perform ball milling and mixing at 500 rpm for 30min; then place the mixed sample after ball milling in a corundum crucible and perform melting treatment at 1450 degrees for 12h; then perform phase separation treatment at 610 degrees for 24h; crush the intermediate after phase separation into 100-200 mesh, then wash it in 0.5mol / l hydrochloric acid at 98 degrees for 24h, perform alkaline washing in 2mol / l sodium hydroxide solution at 40 degrees for 4h, wash it with water until neutral, dry it at 140 degrees, and dry it for 12h to obtain magnetic CPG sample 4.

[0065] Compared with Example 1, the content of ferric oxide in Example 4 is lower, and the content of zirconium oxide is higher.

[0066] [Example 5]

[0067] Weigh 60g of silicon dioxide, 25g of boric acid, 7g of anhydrous sodium carbonate, 10g of ferric oxide, and 5g of zirconium oxide and place them in a 500ml corundum ball mill, and perform ball milling and mixing at 500 rpm for 30min; then place the mixed sample after ball milling in a corundum crucible and perform melting treatment at 1450 degrees for 12h; then perform phase separation treatment at 610 degrees for 24h; crush the intermediate after phase separation into 100-200 mesh, then wash it in 0.5mol / l hydrochloric acid at 98 degrees for 24h, perform alkaline washing in 2mol / l sodium hydroxide solution at 40 degrees for 4h, wash it with water until neutral, and dry it at 140 degrees for 12h to obtain magnetic CPG sample 5.

[0068] Compared with Example 1, the content of ferric oxide in Example 5 is higher and the content of zirconium oxide is higher.

[0069] [Comparative Example 1]

[0070] Weigh 60g of silicon dioxide, 25g of boric acid, 7g of anhydrous sodium carbonate, and 6g of ferric oxide and place them in a 500ml corundum ball mill, and perform ball milling at 500 rpm for 30min; then place the ball-milled sample in a corundum crucible and perform melting treatment at 1450 degrees for 12h; then perform phase separation treatment at 610 degrees for 24h, crush the intermediate after phase separation into 100-200 mesh, then wash in 0.5mol / l hydrochloric acid at 98 degrees for 24h, perform alkaline washing in 2mol / l sodium hydroxide solution at 40 degrees for 4h, wash with water until neutral, and dry at 140 degrees for 12h to obtain magnetic CPG sample 6.

[0071] Compared with Example 1, the raw material in Comparative Example 1 does not contain zirconium oxide component.

[0072] [Comparative Example 2]

[0073] Weigh 60g of silicon dioxide, 25g of boric acid, 7g of anhydrous sodium carbonate, 6g of ferric oxide, and 6g of zirconium oxide and place them in a 500ml corundum ball mill, and perform ball milling at 500 rpm for 30min; then place the ball-milled sample in a corundum crucible and perform melting treatment at 1450 degrees for 12h; then perform phase separation treatment at 610 degrees for 24h, crush the intermediate after phase separation into 100-200 mesh, then wash in 0.5mol / l hydrochloric acid at 98 degrees for 24h, perform alkaline washing in 2mol / l sodium hydroxide solution at 40 degrees for 4h, wash with water until neutral, and dry at 140 degrees for 12h to obtain magnetic CPG sample 7.

[0074] Compared with Example 1, the content of zirconium oxide in Comparative Example 2 is higher.

[0075] [Comparative Example 3]

[0076] Weigh 60g of silicon dioxide, 25g of boric acid, 7g of anhydrous sodium carbonate, 15g of ferric oxide, and 2g of zirconium oxide and place them in a 500ml corundum ball mill, and perform ball milling at 500 rpm for 30min; then place the ball-milled sample in a corundum crucible and perform melting treatment at 1450 degrees for 12h; then perform phase separation treatment at 610 degrees for 24h, crush the intermediate after phase separation into 100-200 mesh, then wash in 0.5mol / l hydrochloric acid at 98 degrees for 24h, perform alkaline washing in 2mol / l sodium hydroxide solution at 40 degrees for 4h, wash with water until neutral, and dry at 140 degrees for 12h to obtain magnetic CPG sample 8.

[0077] Compared with Example 1, the component content of ferric oxide in Comparative Example 3 is higher.

[0078] [Comparative Example 4]

[0079] Weigh 60g of silicon dioxide, 25g of boric acid, 7g of anhydrous sodium carbonate, 2g of ferric oxide, and 2g of zirconium oxide and place them in a 500ml corundum ball mill, and perform ball milling at 500 rpm for 30min; then place the ball-milled sample in a corundum crucible and perform melting treatment at 1450 degrees for 12h; then perform phase separation treatment at 610 degrees for 24h, crush the intermediate after phase separation into 100-200 mesh, then wash in 0.5mol / l hydrochloric acid at 98 degrees for 24h, perform alkaline washing in 2mol / l sodium hydroxide solution at 40 degrees for 4h, wash with water until neutral, and dry at 140 degrees for 12h to obtain magnetic CPG sample 9.

[0080] Compared with Example 1, the component content of ferric oxide in Comparative Example 4 is lower.

[0081] [Comparative Example 5]

[0082] Weigh 60g of silicon dioxide, 25g of boric acid, 7g of anhydrous sodium carbonate, 6g of ferric oxide, and 2g of zirconium oxide and place them in a 500ml corundum ball mill, and perform ball milling at 500 rpm for 30min; then place the ball-milled sample in a corundum crucible and perform melting treatment at 1450 degrees for 12h; then perform phase separation treatment at 500 degrees for 24h, crush the intermediate after phase separation into 100-200 mesh, then wash in 0.5mol / l hydrochloric acid at 98 degrees for 24h, perform alkaline washing in 2mol / l sodium hydroxide solution at 40 degrees for 4h, wash with water until neutral, and dry at 140 degrees for 12h to obtain magnetic CPG sample 10.

[0083] Compared with Example 1, the phase separation temperature in Comparative Example 5 is lower.

[0084] [Comparative Example 6]

[0085] Weigh 60g of silicon dioxide, 25g of boric acid, 7g of anhydrous sodium carbonate, 6g of ferric oxide, and 2g of zirconium oxide and place them in a 500ml corundum ball mill, and perform ball milling at 500 rpm for 30min; then place the ball-milled sample in a corundum crucible and perform melting treatment at 1450 degrees for 12h; then perform phase separation treatment at 700 degrees for 24h, crush the intermediate after phase separation into 100-200 mesh, then wash in 0.5mol / l hydrochloric acid at 98 degrees for 24h, perform alkaline washing in 2mol / l sodium hydroxide solution at 40 degrees for 4h, wash with water until neutral, and dry at 140 degrees for 12h to obtain magnetic CPG sample 11.

[0086] Compared with Example 1, the phase separation temperature in Comparative Example 6 is higher.

[0087] The following Appendix 1 is a statistical table of raw material components and phase separation temperatures in the preparation of magnetic samples 1 to 11 in the above-mentioned Examples 1 to 5 and Comparative Examples 1 to 6:

[0088] Appendix 1 Statistics of raw material composition and phase separation temperature

[0089]

[0090] Note: The wt% in Appendix 1 is the percentage of the component in the total mass of the raw materials.

[0091] The magnetic CPG samples 1 to 11 prepared above were tested for particle density, porosity and pore size distribution using a high-performance fully automatic pressure pump instrument Autopore IV 9500; the magnetic strength and coercive force were tested using a vibrating magnetometer; the corrosion resistance, pore size formation and particle dispersion of the magnetic CPG were observed using a scanning electron microscope. For details, see Appendix 2 and Figures 1 to 8 .in, Figure 1 to Figure 3 The pore size distribution diagrams corresponding to magnetic CPG samples 1 to 3 are shown in Figure 1. Figures 1 to 3 It describes the pore size distribution density function, that is, the entire pore size distribution range is divided into a number (or countless) of pores with a unit of 1nm. If there is a pore on a certain nm, then the pore volume value of this pore is represented by the vertical coordinate.

[0092] Appendix 2 Parameters and characteristics statistics

[0093]

[0094] Pass Schedule 1, Schedule 2 and Figures 1 to 8 The following conclusions can be drawn:

[0095] Reference Figure 5 and Figure 6 , namely the high-power scanning electron microscope image of magnetic CPG sample 1 and the scanning electron microscope image of magnetic CPG sample 6. It can be seen from the combination of Appendix 1 and Appendix 2 that the introduction of zirconium oxide into the raw material in Example 1 enhances the corrosion resistance of magnetic CPG sample 1 and has a certain promoting effect on the magnetic strength of magnetic CPG sample 1. In comparative example 1, the raw material does not contain zirconium oxide components, and the treated magnetic CPG sample 6 is severely corroded by acid and alkali;

[0096] Reference Figure 1 to Figure 3 That is, the pore size distribution diagram of magnetic CPG sample 1, magnetic CPG sample 2 and magnetic CPG sample 3. In Example 2, the phase separation temperature of magnetic CPG sample 2 is lower at low silicon content, and in Example 3, the phase separation temperature of magnetic CPG sample 3 is higher at high silicon content. Compared with magnetic CPG sample 1 in Example 1, magnetic CPG sample 2 and magnetic CPG sample 3 can obtain magnetic CPG products with similar pore size and pore size distribution, and the pore size and pore size distribution are uniform.

[0097] Referring to Appendix 1 and Appendix 2, the magnetic CPG samples 4 and 5 prepared in Examples 4 and 5 are compared with the magnetic CPG sample 1 in Example 1, and magnetic CPG products with similar pore size and pore size distribution can be obtained, and the pore size and pore size distribution are uniform.

[0098] Reference Figure 5 and Figure 7 That is, the scanning electron microscope images of magnetic CPG sample 1 and magnetic CPG sample 7, compared with Example 1, when the zirconium oxide content of magnetic CPG sample 7 in comparative example 2 is higher than 5% of the total weight, the pore size is severely blocked and the porosity is low, and it cannot be effectively used as a carrier material for gene synthesis;

[0099] Referring to Appendix 1 and Appendix 2, magnetic CPG sample 8 and magnetic CPG sample 9 are compared with magnetic CPG sample 1 in Example 1. It can be seen that when the content of ferric oxide in comparative example 3 is higher than 10%, the magnetic CPG sample 8 obtained exhibits non-superparamagnetism, and when the content of ferric oxide in comparative example 4 is lower than 5%, the magnetic strength of magnetic CPG sample 9 obtained is weaker than that of magnetic CPG sample 1.

[0100] Refer to Schedule 1, Schedule 2 and Figure 8 By comparing the magnetic CPG samples 10 and 11 with the magnetic CPG sample 1 prepared in Example 1, it can be concluded that the phase separation temperature has a great influence on the pore formation and superparamagnetic properties. The pore structure of the magnetic CPG sample 10 obtained in Example 5 at a phase separation temperature below 550 degrees is in a broken state, and the magnetic CPG sample 11 obtained in Example 6 at a phase separation temperature above 650 degrees exhibits non-superparamagnetism.

[0101] Thus, the magnetic CPG samples 1 to 5 prepared in Examples 1 to 5 are mainly made of 55% to 65% silicon dioxide, 20% to 30% boric acid, 6% to 7% sodium carbonate, 5% to 10% ferric oxide and 2% to 5% zirconium oxide as raw materials, and are prepared at a phase separation temperature of 550°C to 650°C. The obtained magnetic CPG samples 1 to 5 have excellent corrosion resistance and mechanical strength, high porosity, and uniform pore size and pore size distribution, stable superparamagnetism, and monodispersity without an external magnetic field, so they can meet the performance requirements of gene synthesis carrier materials; the magnetic CPG sample 6 obtained in Comparative Example 1 has poor corrosion resistance due to the lack of zirconium oxide component; the magnetic CPG sample 7 obtained in Comparative Example 2 introduces more than 5% by mass of zirconium oxide, resulting in pore blockage Serious, the porosity is reduced; the ferric oxide content in the raw material components of Comparative Examples 3 and 4 does not meet 5%-10%, so that the magnetic CPG sample 8 and the magnetic CPG sample 9 have poor particle dispersibility or cannot present stable superparamagnetism; the phase separation temperature of Comparative Examples 5 and 6 does not meet 550℃-650℃, and the prepared magnetic CPG sample 10 and the magnetic CPG sample 11 cannot maintain an intact pore structure or stable superparamagnetism; Due to the large differences in the content of each raw material component and the phase separation temperature in Comparative Examples 1-6, the prepared magnetic CPG samples 6-11 cannot simultaneously take into account the corrosion resistance, mechanical strength, uniform pore size and pore size distribution, higher porosity, stable supersequentiality and monodispersity of the magnetic CPG without an external magnetic field, and cannot meet the performance requirements of gene synthesis carrier materials.

[0102] Please refer to Fig. 9 In the embodiment of the present invention, magnetic CPG is used as a carrier for oligonucleotide synthesis in oligonucleotide synthesis, and the specific operation steps are as follows:

[0103] The magnetic CPG sample 1 prepared in Example 1 is loaded into a DNA synthesis column, and the DNA synthesis column is placed in an ABI DNA synthesizer to gradually synthesize oligonucleotides of the poly(dT)20 sequence. After the synthesis is completed, the product is transferred to a centrifuge bottle filled with acetonitrile, 10 ml of 2% DBU catalyst is added to the acetonitrile, and the centrifuge bottle is rotated at room temperature for 1 hour to react to remove the protective group of the phosphate molecule; at the end of the reaction, the product is washed with 300 ml of acetonitrile and 300 ml of dichloromethane, and 3'-coupled Oligo(dT)20 is obtained after drying. The obtained 3'-coupled Oligo(dT)20-coupled magnetic CPG can be used for the purification of gene complementary sequences. The purification process is briefly as follows: Fig. 9 shown.

[0104] In summary, the magnetic CPG, preparation method and application provided by the embodiments of the present invention are designed through the design of raw material components and preparation method, and the components of the magnetic CPG include silicon dioxide, boric acid, sodium carbonate, ferric oxide and zirconium oxide; in terms of mass percentage, 55% to 65% of silicon dioxide and 6% to 7% of sodium carbonate can effectively form a porous structure of the magnetic CPG; 55% to 65% of silicon dioxide and 2% to 5% of zirconium oxide can improve the mechanical strength of the porous structure of the magnetic CPG; 20% to 30% of boric acid and 2% to 5% of zirconium oxide can increase the porosity and specific surface area of ​​the magnetic CPG, thereby increasing the effective sites when used as a gene synthesis vector; 5% to 10% of ferric oxide can make the magnetic CPG have stable superparamagnetism; among the above components, 2% to 5% of zirconium oxide can also improve the corrosion resistance of the magnetic CPG, making the magnetic CPG not easily corroded.

[0105] The magnetic CPG prepared by the above components at a phase separation temperature of 550℃~650℃ has excellent corrosion resistance and mechanical strength, uniform pore size and pore size distribution, and high porosity; at the same time, it exhibits stable superparamagnetism and maintains monodispersity in the absence of an external magnetic field, which will play a strong role in promoting the domestic gene synthesis industry, oligonucleotide drug research and other fields.

Claims

1. A nanoporous glass with controllable magnetic pore size, characterized in that: The magnetic pore-controllable nanoporous glass is mainly made of silicon dioxide, boric acid, sodium carbonate, ferric oxide and zirconium oxide as raw materials; The raw materials include, by mass percentage, 55% to 65% silicon dioxide, 20% to 30% boric acid, 6% to 7% sodium carbonate, 5% to 10% ferric oxide and 2% to 5% zirconium oxide; Wherein, the phase separation temperature when preparing the magnetic pore-controllable nanoporous glass is 550°C to 650°C.

2. The nanoporous glass with controllable magnetic aperture according to claim 1, characterized in that: The density of the magnetic pore-controllable nanoporous glass is 0.25 g / ml to 0.35 g / ml.

3. The nanoporous glass with controllable magnetic aperture according to claim 1 or 2, characterized in that: The porosity of the magnetic pore-controllable nanoporous glass is 76% to 94%; and / or The magnetic intensity of the nanoporous glass with controllable magnetic pore size is 12emu / g to 32emu / g.

4. The nanoporous glass with controllable magnetic aperture according to claim 1 or 2, characterized in that: The magnetic pore-controllable nanoporous glass includes at least one hydroxyl group.

5. A method for preparing the nanoporous glass with controllable magnetic pore size according to any one of claims 1 to 4, characterized in that: include: Silicon dioxide, boric acid, sodium carbonate, ferric oxide and zirconium oxide are mixed and ball-milled to obtain a mixed sample; Performing a melting process on the mixed sample to obtain a melted sample; Performing phase separation treatment on the melted sample at a temperature of 550° C. to 650° C. to obtain an intermediate; The intermediate is post-treated to obtain nanoporous glass with controllable magnetic pore size.

6. The preparation method according to claim 5, characterized in that: The post-treatment of the intermediate is to perform acid or alkali washing on the intermediate.

7. The preparation method according to claim 6, characterized in that: The acid-base washing treatment of the intermediate comprises: The intermediate is crushed and then subjected to acid and alkali washing; The intermediate is subjected to acid and alkali washing treatment and then dried.

8. The preparation method according to claim 7, characterized in that: In the crushing process, the intermediate is crushed to 100-200 meshes; In the acid-base washing treatment, the intermediate is washed in an acidic solution and an alkaline solution, and then washed with water until neutral; In the drying process, the temperature of the drying process is 120° C. to 160° C., and the time is 10 h to 14 h.

9. The preparation method according to claim 5, characterized in that: The ball milling process is performed at a speed of 450 to 550 rpm for 20 to 40 min. The mixed sample is subjected to a melting treatment at a temperature of 1400°C to 1500°C.

10. Use of the nanoporous glass with controllable magnetic pore size as claimed in any one of claims 1 to 4 as a carrier for oligonucleotide synthesis.

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