生物模板法制备磁性中空微球的方法和应用

磁性中空微球在功能性吸附、酶固定化载体、物质的分离纯化、活性物质和药物的封装与控释、靶向给药、污染防治、食品和材料学等领域有突出的应用价值。文章综述了利用生物模板法制备磁性中空微球的制备原理和最新研究成果，并主要分析了软模板法和自模板法两种制备工艺。软模板法工艺主要通过吸附-高温炭化法除去生物模板材料获得固定外形的磁性中空微球。自模板法制备磁性中空微球可依据生物材料自身成分经水热碳化反应或在惰性气体氛围保护下的高温炭化反应生成具有特殊官能团结构的中空碳微球，并将磁性物质溶入或吸附到中空微球中，具体分为水热碳化法和浸渍-高温炭化法；也可将制备好的磁性物质吸附于经过特殊处理过的生物模板材料表面，如吸附-共沉淀法和高温炭化-共沉淀法。总之，生物模板法制备磁性中空微球条件较为温和、无污染，生物模板材料对人体无毒，特别适合于食品、医药等行业的应用，具有很好的生产应用前景。

Methods and application of magnetic hollow microsphere prepared from bio-template

Magnetic hollow microsphere has the prominent application in functional adsorption, immobilized carriers of enzyme, separation and purification of substances, encapsulation and controlled release of active substance and medicine, targeted drug delivery, contaminant prevention, food and material science. The article summarizes the preparation principle of magnetic hollow microsphere by bio-template method and research achievement, and mainly analyzes the two preparation technologies, soft template method and self-template method. Soft-template technologies adopt adsorption-calcination method for obtaining stable shapes of the microsphere when removing template materials. Self-template technologies adopt the methods of hydrothermal carbonization or calcination under the protection of inert gas to create special groups on the surface of hollow microsphere and hollow spherical structure which cause the magnetic substances to be adsorbed on and enter into the microspheres, and they can be classified as hydrothermal carbonization method and dipping-calcination method. Besides, the adsorption of magnetic substances on the surface of pretreated bio-template is another way, such as adsorption-coprecipitation and calcination-coprecipitation. In conclusion, the conditions of preparing magnetic hollow microsphere by bio-template are gentle and non-contaminant, and moreover, bio-template materials are nontoxic, so it will have the wide application in food processing and pharmaceutical industry.