摘要
酪素作为一种天然产物蛋白质,既可以溶于酸也可以溶于碱。酪素溶解在氨水中所形成的膜不易溶于水,酪素和硼砂形成的溶液耐贮存且具有抗腐败的作用,因此,在实际操作中通常采用硼砂和氨水来溶解酪素。然而,单纯溶解酪素已不能满足现代工业的需求,为更好地应用于现代工业领域,需要对酪素进行一定程度的功能化改性。一般情况下,相比于未改性的酪素,改性酪素具有以下优点:(1)耐水性能更高;(2)成膜柔韧性更高;(3)耐微生物稳定性更高;(4)具有自清洁性、抗紫外性能和药物缓释等特殊性能。初期,多数研究者们通过引入聚合物单体来对酪素进行改性,以期提高酪素的耐水性或成膜性能。但随着科技的发展,人们对功能化产品的需求日益增大。为了赋予酪素特殊的功能,近几年有相关研究者采用无机纳米粒子对酪素进行改性,并采用不同的方法在酪素体系中引入不同的纳米粒子对其进行改性,使纳米粒子赋予酪素基体特殊的功能。截至目前,向酪素中引入纳米氧化锌(ZnO)、纳米二氧化钛(TiO2)和纳米四氧化三铁(Fe3O4)等纳米粒子来改性酪素的研究已取得了初步成功,这些纳米粒子的引入可赋予酪素体系抗菌、自清洁和缓释等特殊性能。其中,采用单原位聚合法将纳米ZnO引入己内酰胺改性酪素的体系中,制得酪素基纳米ZnO复合乳液并将其应用于皮革涂饰,可赋予体系一定的抗菌性能;采用双原位聚合法将纳米TiO2引入聚丙烯酸酯改性酪素体系中,制得酪素基纳米TiO2复合乳液并将其应用于皮革涂饰,可赋予体系自清洁性能;通过设计微胶囊结构,将纳米Fe3O4包覆在酪素胶束中,在外加磁场的作用下,应用到可控药物释放领域可赋予体系缓释功能。此外,还可在酪素体系中引入氧化石墨烯(GO)或蒙脱土(MMT)等纳米材料,赋予体系不同的特殊功能,使其应用更加广泛。本文归纳了功能化改性酪素和酪素基复合材料的研究进展,分别就聚合物和无机纳米粒子对酪素的改性方法进行介绍,分析了自1993年以来改性酪素产品在各个行业的应用,同时对酪素今后的发展趋势进行了展望,为研发更多适用于不同领域的高性能功能型酪素产品提供指导。
As a natural protein,casein can be dissolved in both acid and alkali medium.Since the film formed by casein dissolving in ammonia water are resistant to water and spoilage,respectively.So borax and ammonia water are usually used to dissolve casein in industry.However,pristine casein can’t meet the needs of modern industry.Therefore,modification of casein is required.In general,modified casein has the following advantages over unmodified casein:(ⅰ)improved water resistance,(ⅱ)enhanced flexibility of films,(ⅲ)improved microbial stability,(ⅳ)special functions,such as self-cleaning,anti-ultraviolet performance and controlled releasing behaviors.In the early days,casein was modified by introducing polymer monomers to improve its film water resistance or film-forming properties.Howe-ver,with the increasing demand for functionalized products,researchers attempted employing inorganic nanoparticles to modify casein in order to give the special functionality to casein film recently years.Different methods have been used to introduce various nanoparticles in casein system for special functions.Up to now,the successful examples of nanoparticle-modified casein involved nano zinc oxide(ZnO),nano titanium dioxide(TiO 2)and nano ferric oxide(Fe 3O 4),which can endow casein matrix with antibacterial,self-cleaning and slow releasing properties.Such as,nano-ZnO was introduced into the caprolactam-modified casein matrix by single in-situ polymerization method to prepare casein-based nano-ZnO composite emulsion,which was applied to leather finishing and showed obvious antibacterial properties.Nano-TiO 2 was introduced into the polyacrylate-modified casein system by double in-situ polymerization,and the casein-based nano-TiO 2 hybrid emulsion applied to leather could endow the system with self-cleaning performance.Nano-Fe 3O 4 was also designed as a microcapsule structure and coated on casein micelles.Under the action of external magnetic field,it can be applied to the controlled drug release field to give the system a sustained release function.In addition,graphene oxide(GO),montmorillonite(MMT),etc.could also be introduced into the casein system to offer different special functions,which make it more widely available.This article summarizes the research progress on modification methods and functional modification of casein-based composites,mainly introduces casein modified by polymer and inorganic nanoparticles.The application of casein products in various industries since 1993 is also described.At the same time,the development trend of modified casein in the future is prospected,which will provide reference for obtaining functio-nalized casein products in various fields.
作者
安文
马建中
徐群娜
AN Wen;MA Jianzhong;XU Qunna(National Demonstration Center for Experimental Light Chemistry Engineering Education,College of Bioresources Chemical and Materials Engineering,Shaanxi University of Science & Technology,Xi’an 710021;Shaanxi Research Institute of Agricultural Products Processing Technology,Xi’an 710021)
出处
《材料导报》
EI
CAS
CSCD
北大核心
2019年第15期2602-2609,共8页
Materials Reports
基金
国家重点研发计划(2017YFB0308602)
陕西省重点科技创新团队(2013KCT-08)
陕西省高校科协人才托举计划项目(20180416)~~
关键词
酪素
改性
纳米材料
功能化
casein
modified
nano materials
functionalization
