Preparation method of silver phosphate-containing calcium alginate antibacterial hydrogel filtering membrane
阅读说明：本技术 一种含磷酸银的海藻酸钙抗菌水凝胶过滤膜的制备方法 (Preparation method of silver phosphate-containing calcium alginate antibacterial hydrogel filtering membrane ) 是由 赵孔银 白甜 谢文宾 郭智龙 路子杰 李佳成 李子逸 王晓磊 魏俊富 于 2019-11-26 设计创作，主要内容包括：针对海藻酸钙水凝胶强度低、易溶胀、易滋生细菌等造成海藻酸钙水凝胶过滤膜难以长期使用的问题,本发明公开了一种含磷酸银的海藻酸钙抗菌水凝胶过滤膜的制备方法。首先将过量可溶性磷酸盐与硝酸银反应,生成磷酸银和可溶性磷酸盐的混合物水溶液,然后溶解海藻酸钠,得到铸膜液。将该铸膜液用玻璃棒刮膜,并浸泡于过量可溶性钙盐水溶液中充分交联,在生成海藻酸钙水凝胶的同时,在水凝胶中原位生成磷酸钙,且磷酸钙将磷酸银包裹,避免了其在海藻酸钙水凝胶中的流失。磷酸钙与海藻酸盐通过钙离子交联生成有机无机杂化结构,再加上其物理增强作用,提高了海藻酸钙水凝胶的机械强度,降低了其溶胀性能。磷酸银赋予了水凝胶良好的抗菌性能。(The invention discloses a preparation method of a silver phosphate-containing calcium alginate antibacterial hydrogel filtering membrane, aiming at the problem that the calcium alginate hydrogel filtering membrane is difficult to use for a long time due to low strength, easy swelling, easy bacteria breeding and the like of the calcium alginate hydrogel. Firstly, reacting excessive soluble phosphate with silver nitrate to generate a mixture water solution of silver phosphate and the soluble phosphate, and then dissolving sodium alginate to obtain a membrane casting solution. The casting solution is scraped by a glass rod and is soaked in an excessive soluble calcium salt aqueous solution for full crosslinking, calcium phosphate is generated in situ in the hydrogel while the calcium alginate hydrogel is generated, and the calcium phosphate wraps the silver phosphate, so that the loss of the calcium phosphate in the calcium alginate hydrogel is avoided. Calcium phosphate and alginate are crosslinked through calcium ions to generate an organic-inorganic hybrid structure, and the physical enhancement effect of the calcium phosphate and the alginate improves the mechanical strength of the calcium alginate hydrogel and reduces the swelling performance of the calcium alginate hydrogel. The silver phosphate endows the hydrogel with good antibacterial performance.)
1. A preparation method of a silver phosphate-containing calcium alginate antibacterial hydrogel filtering membrane is characterized by comprising the following steps:
a) preparing a soluble phosphate aqueous solution with the mass percentage concentration of 0.1-20%;
b) preparing silver nitrate water solution with mass percent concentration of 0.1-20%;
c) dropwise adding the soluble phosphate aqueous solution obtained in the step a) into the silver nitrate aqueous solution obtained in the step b) until the soluble phosphate is excessive to obtain a mixture solution of silver phosphate and the soluble phosphate, dissolving sodium alginate with the mass percentage concentration of 0.2-8% in the mixture solution, and standing and defoaming to obtain a casting solution;
d) preparing soluble calcium salt water solution with mass percent concentration of 0.2-20% as coagulating bath;
e) pouring the casting solution obtained in the step c) on a dry and clean glass plate, strickling the glass plate by using a glass rod with two ends wound with copper wires with the diameter of 20-1500 mu m, immediately putting the glass plate and the strickled film into the coagulation bath obtained in the step d) for soaking for 5-240min, reacting soluble calcium salt with sodium alginate to generate calcium phosphate hydrogel, and simultaneously generating calcium phosphate with soluble phosphate in the calcium alginate hydrogel, and wrapping silver phosphate by the calcium phosphate to avoid the loss of the silver phosphate in the calcium alginate hydrogel; calcium phosphate salt and alginate are crosslinked through calcium ions to generate an organic-inorganic hybrid structure, and the physical enhancement effect is added, so that the mechanical strength of the calcium alginate hydrogel is improved, and the swelling rate of the calcium alginate hydrogel is reduced;
f) and finally, soaking the filter membrane in deionized water and repeatedly washing to remove inorganic salts remained on the membrane neutralization surface, thereby obtaining the silver phosphate-containing calcium alginate antibacterial hydrogel filter membrane.
2. The method for preparing the silver phosphate-containing calcium alginate antibacterial hydrogel filtering membrane according to claim 1, wherein the soluble phosphate is any one or a mixture of two or more of diammonium phosphate, disodium phosphate, dipotassium phosphate, tripotassium phosphate and trisodium phosphate.
3. The method for preparing the silver phosphate-containing calcium alginate antibacterial hydrogel filtering membrane as claimed in claim 1, wherein the soluble calcium salt is any one or a mixture of two or more of calcium chloride, calcium nitrate, calcium dihydrogen phosphate and calcium gluconate.
4. The preparation method of the calcium alginate antibacterial hydrogel filtering membrane containing the silver phosphate as claimed in claim 1, wherein the silver phosphate endows the calcium alginate hydrogel with good antibacterial performance, thereby preventing the calcium alginate hydrogel filtering membrane from being degraded by bacteria in the using process.
5. The method for preparing the silver phosphate-containing calcium alginate antibacterial hydrogel filtering membrane as claimed in claim 1, wherein the swelling rate of the silver phosphate-containing calcium alginate antibacterial hydrogel filtering membrane obtained by the preparation method in physiological saline is 20% -75% of the swelling rate of the calcium alginate membrane in physiological saline.
6. The method for preparing the silver phosphate-containing calcium alginate antibacterial hydrogel filtering membrane as claimed in claim 1, wherein the antibacterial rate of the silver phosphate-containing calcium alginate antibacterial hydrogel filtering membrane on escherichia coli is 75-100%.
7. The preparation method of the silver phosphate-containing calcium alginate antibacterial hydrogel filtering membrane as claimed in claim 1, which is characterized by simple preparation method and green and environment-friendly preparation process, and the obtained silver phosphate-containing calcium alginate antibacterial hydrogel filtering membrane has good pollution resistance and good application prospect in dye desalination, brown sugar decolorization and protein purification.
Technical Field
The invention relates to a preparation method of a silver phosphate-containing calcium alginate antibacterial hydrogel filtering membrane, belonging to the field of functional materials and membrane separation.
The invention relates to the technical fields of antibiosis, filtering membranes, hydrogel and the like. In particular to a preparation method of a calcium alginate antibacterial hydrogel filtering membrane containing silver phosphate.
Background
Water resource shortages and pollution widely impact the sustainable development of industrial and social activities and are one of the most critical global challenges facing mankind in the 21 st century. Currently, a range of sustainable water purification techniques have been developed, such as air flotation, flocculation, adsorption, distillation and Advanced Oxidation Processes (AOPs). However, complex contaminants in wastewater (such as inorganic salts, organics, and microorganisms) require constant renewal of technology to meet increasingly stringent water quality standards. In addition, the above techniques mostly have the problems of complex equipment, high energy consumption, high operation cost and the like, and can generate chemical pollutants, so that the wastewater treatment is more complex. Therefore, it is important to develop sustainable water purification technology that is environmentally friendly, energy-saving, and low-cost. The membrane separation technology is an environment-friendly new technology, and compared with the traditional wastewater treatment method, the membrane separation technology does not produce secondary pollution, has low energy consumption and simple operation, and is one of the most promising water treatment technologies [ j.hazard.mater, 2016, 308: 75-83 deg.
When the traditional polymer filter membrane is prepared, a polymer is firstly dissolved in an organic solvent, then phase transition is carried out in a water-phase coagulating bath to form a membrane, and a membrane structure with a compact surface and a large number of finger-shaped holes in the interior is usually formed. Most membranes do not have organic degradability and antimicrobial activity. However, having degradable and antimicrobial propertiesMembranes are essential in practical applications. Silver has a long history as an antimicrobial agent. Although the elemental metallic silver is relatively inactive, silver ions have a destructive effect on a wide range of bacteria. When low concentrations of silver ions accumulate in cells, they can bind to negatively charged components in proteins and nucleic acids, thereby affecting structural changes in the bacterial cell wall, cell membrane and nucleic acids, and thus their viability. Ag3PO4Is light yellow solid powder at normal temperature, is odorless, is soluble in acid, potassium cyanide solution and ammonia water, is slightly soluble in water and acetic acid, and turns brown under heating or light irradiation. Ag3PO4Although known for high activity, it has problems of photo-corrosion and poor stability, and the photo-stability can be improved by surface modification. Preparation of Ag at present3PO4The method comprises the following steps: ion exchange, solvothermal, precipitation, impregnation, and the like. Wherein, the ion exchange method is used for preparing Ag3PO4The method has the advantages of simple process, low requirement on equipment, low cost and the like.
The polymer gel is a multi-element system consisting of a polymer three-dimensional network and a solvent, and the hydrogel has good hydrophilicity because the hydrogel contains more than 80% of water. Sodium alginate is a natural high molecular substance which can be extracted from kelp or brown algae, has wide sources and low price, and is widely applied to the fields of food, biological medicine, wastewater treatment and the like at present. Sodium alginate and calcium ions can form hydrogel through ionic crosslinking. In our previous research, a series of calcium alginate-based hydrogel filtration membranes were prepared [ patent ZL201310424398.7, ZL201310424399.1, ZL201310424397.2 ], which have good anti-pollution performance but have the disadvantages of poor mechanical properties, low mechanical strength and easy degradation by bacteria.
The invention discloses a preparation method of a silver phosphate-containing calcium alginate antibacterial hydrogel filtering membrane, aiming at the problem that the calcium alginate hydrogel filtering membrane is difficult to use for a long time due to low strength, easy swelling, easy bacteria breeding and the like of the calcium alginate hydrogel. Firstly, reacting excessive soluble phosphate with silver nitrate to generate a mixture water solution of silver phosphate and the soluble phosphate, and then dissolving sodium alginate to obtain a membrane casting solution. The casting solution is scraped by a glass rod and is soaked in an excessive soluble calcium salt aqueous solution for full crosslinking, calcium phosphate is generated in situ in the hydrogel while the calcium alginate hydrogel is generated, and the calcium phosphate wraps the silver phosphate, so that the loss of the calcium phosphate in the calcium alginate hydrogel is avoided. Calcium phosphate and alginate are crosslinked through calcium ions to generate an organic-inorganic hybrid structure, and the physical enhancement effect of the calcium phosphate and the alginate improves the mechanical strength of the calcium alginate hydrogel and reduces the swelling rate of the calcium alginate hydrogel. The silver phosphate endows the hydrogel with good antibacterial performance.
Disclosure of Invention
Aiming at the defects of the prior art, the invention aims to solve the technical problems that the traditional filtering membrane is not polluted, has poor hydrophilicity, low strength of the calcium alginate hydrogel filtering membrane, is easy to degrade by bacteria and the like.
The invention provides a preparation method of a silver phosphate-containing calcium alginate antibacterial hydrogel filtering membrane, which solves the problems that the traditional filtering membrane is not polluted, has poor hydrophilicity, is low in strength of the calcium alginate hydrogel filtering membrane, is easy to degrade by bacteria and the like.
The invention provides a preparation method of a silver phosphate-containing calcium alginate antibacterial hydrogel filtering membrane, which is characterized by comprising the following steps:
a) preparing a soluble phosphate aqueous solution with the mass percentage concentration of 0.1-20%;
b) preparing silver nitrate water solution with mass percent concentration of 0.1-20%;
c) dropwise adding the soluble phosphate aqueous solution obtained in the step a) into the silver nitrate aqueous solution obtained in the step b) until the soluble phosphate is excessive to obtain a mixture solution of silver phosphate and the soluble phosphate, dissolving sodium alginate with the mass percentage concentration of 0.2-8% in the mixture solution, and standing and defoaming to obtain a casting solution;
d) preparing soluble calcium salt water solution with mass percent concentration of 0.2-20% as coagulating bath;
e) pouring the casting solution obtained in the step c) on a dry and clean glass plate, strickling the glass plate by using a glass rod with two ends wound with copper wires with the diameter of 20-1500 mu m, immediately putting the glass plate and the strickled film into the coagulation bath obtained in the step d) for soaking for 5-240min, reacting soluble calcium salt with sodium alginate to generate calcium phosphate hydrogel, and simultaneously generating calcium phosphate with soluble phosphate in the calcium alginate hydrogel, and wrapping silver phosphate by the calcium phosphate to avoid the loss of the silver phosphate in the calcium alginate hydrogel; calcium phosphate salt and alginate are crosslinked through calcium ions to generate an organic-inorganic hybrid structure, and the physical enhancement effect is added, so that the mechanical strength of the calcium alginate hydrogel is improved, and the swelling rate of the calcium alginate hydrogel is reduced;
f) and finally, soaking the filter membrane in deionized water and repeatedly washing to remove inorganic salts remained on the membrane neutralization surface, thereby obtaining the silver phosphate-containing calcium alginate antibacterial hydrogel filter membrane.
The soluble phosphate is any one or a mixture of two or more of diammonium hydrogen phosphate, disodium hydrogen phosphate, dipotassium hydrogen phosphate, tripotassium phosphate and trisodium phosphate; the soluble calcium salt is one or a mixture of two or more of calcium chloride, calcium nitrate, calcium dihydrogen phosphate and calcium gluconate.
The silver phosphate endows the calcium alginate hydrogel with good antibacterial performance, and the calcium alginate hydrogel filtering membrane is prevented from being degraded by bacteria in the using process. The antibacterial rate of the calcium alginate antibacterial hydrogel filtering membrane containing the silver phosphate to escherichia coli is 75-100%. The swelling rate of the filter membrane in normal saline is 20-75% of that of the calcium alginate membrane in normal saline.
The invention has the advantages that: the preparation method is simple, the preparation process is green and environment-friendly, and the obtained silver phosphate-containing calcium alginate antibacterial hydrogel filtering membrane has good anti-swelling, anti-pollution and antibacterial properties, and has good application prospects in dye desalination, brown sugar decolorization and protein purification.
Detailed Description
Specific examples of the present invention will be described below, but the present invention is not limited to the examples.