纯水相体系超声雾化法制备荧光磁性纳米纤维素微球  

Preparation of fluorescent magnetic nanocellulose microspheres by ultrasonic atomization in pure aqueous phase

作　　者：管庆顺 左克曼 吴伟兵[1] 景宜[1] 戴红旗[1] 房桂干[2] GUAN Qingshun;ZUO Keman;WU Weibing;JING Yi;DAI Hongqi;FANG Guigan(Jiangsu Co-Innovation Center for Efficient Processing and Utilization of Forest Resources,Jiangsu Provincial Key Lab of Pulp&;Paper Science&;Technology,College of Light Industry and Food Engineering,Nanjing Forestry University,Nanjing 210037,China;Institute of Chemical Industry of Forest Products,CAF,Nanjing 210042,China)

机构地区：[1]南京林业大学,江苏省林业资源高效加工利用协同创新中心,江苏省制浆造纸科学与技术重点实验室,轻工与食品学院,南京210037 [2]中国林业科学研究院林产化学工业研究所,南京210042

出　　处：《林业工程学报》2018年第6期68-74,共7页Journal of Forestry Engineering

基　　金：江苏省自然科学基金(BK20171450);国家重点研发计划项目(2017YFD0601005);江苏高校优势学科建设工程资助项目(PAPD)。

摘　　要：以水溶性荧光Cd Te量子点和超顺磁性Fe3O4纳米粒子为负载物质,以羧基化纳米纤维素为载体,结合超声雾化冷冻成型、物理包埋和Ca^(2+)的交联固化制备了均一的荧光磁性纳米纤维素(NFCs)微球,制备过程绿色环保。采用场发射扫描电子显微镜(SEM)、X射线衍射仪(XRD)、红外光谱仪(FT-IR)、光纤光谱仪、激光扫描共聚焦显微镜、振动样品磁强计等对微球的形貌结构、化学组分、荧光(PL)强度和磁性能进行了表征。结果表明,微球为由纳米纤丝互相缠绕形成的多孔球形结构,粒径约5μm。在水溶液中,NFCs表面羧基与Ca^(2+)产生静电交联,在微球内部形成稳定的三维网络结构,而Cd Te量子点和Fe3O4纳米粒子与纤维素分子上的羟基和羧基形成氢键作用,被有效固定在微球的三维网络结构中。负载两种纳米粒子后的微球同时具有超顺磁性和荧光性,且负载前后纳米粒子的晶型和纳米纤维素的分子结构不受影响。此外,微球的三维网络结构限制了量子点之间的聚集,同时球壳保护减少了外界环境对量子点的荧光发射的影响,荧光发射强度高且稳定。Fluorescent and magnetic microspheres are widely used in biomedical fields such as bioseparation,drugtargeting,cellisolation,enzymeimmo-bilization,protein purification,and waste-water treatment due to their excellent properties.In this paper,the high-performance fluorescent and magnetic nanocellulose microspheres were prepared by a simple method in aqueous phase,which included the ultrasonic atomization,physical embedding,as well as crosslinking and curing by Ca^2+.Among them,self-made water-soluble CdTe quantum dots and Fe3O4 nanoparticles were utilized as fluorescent,and magnetic labels and carboxylated nanocelluloses(NFCs)were used as microsphere matrix.The microstructure,chemical composition,photoluminescence(PL)intensity and magnetic performance of the microspheres were examined by the scanning electron microscopy(SEM),X-ray diffraction(XRD),attenuated total reflectance Fourier transform infrared(FT-IR)spectroscopy,luminescence spectrometer,laser scanning confocal microscope and vibrating sample magnetometer.The results showed that the microspheres had porous spherical structure formed by the entanglement of nanofibrils,and the average particle sizes were about 5μm in diameter.The carboxyl on the surface of the nanocellulose was electrostatically cross-linked with Ca^2+,and a stable three-dimensional network structure was formed within the microspheres.The CdTe quantum dots and Fe3O4 nanoparticles were efficiently fixed in the three-dimensional network of microspheres via hydrogen bonding with hydroxyl and carboxyl on nanocellulose.The crystal structure of nanoparticles and the molecular structure of nanocelluloses were not affected during the preparation process.The obtained microspheres possessed good superparamagnetism and strong fluorescence emission.Because the three-dimensional network structure of the microspheres limited the aggregation between quantum dots,the spherical shell reduced the influence of solvent medium on the PL intensity of quantum dots,and the microspheres showed high and stable fluo

关 键 词：纳米纤维素 荧光微球 量子点 磁性纳米粒子 超声雾化 

分 类 号：TB34[一般工业技术—材料科学与工程]