Mansfield Edward D H, Pandya Yash, Mun Ellina A, Rogers Sarah E, Abutbul-Ionita Inbal, Danino Dganit, Williams Adrian C, Khutoryanskiy Vitaliy V
School of Pharmacy, University of Reading Whiteknights Reading Berkshire RG6 6AD UK
ISIS Spallation Neutron Source, Science and Technology Facilities Council, Rutherford Appleton Laboratory, Harwell Science and Innovation Campus Didcot OX11 0QX UK.
RSC Adv. 2018 Feb 8;8(12):6471-6478. doi: 10.1039/c7ra08716k. eCollection 2018 Feb 6.
Functionalising nanoparticles with polymers has gained much interest in recent years, as it aids colloidal stability and manipulation of surface properties. Here, polymer-coated thiolated silica nanoparticles were synthesised by self-condensation of 3-mercaptopropyltrimethoxysilane in the presence of hydroxyethylcellulose. These nanoparticles were characterised by dynamic light scattering, small angle neutron scattering, Nanoparticle Tracking Analysis, Raman spectroscopy, FT-IR spectroscopy, thermogravimetric analysis, Ellman's assay, transmission electron microscopy and cryo-transmission electron microscopy. It was found that increasing the amount of hydroxyethylcellulose in the reaction mixture increased the nanoparticle size and reduced the number of thiol groups on their surface. Additionally, by utilising small angle neutron scattering and dynamic light scattering, it was demonstrated that higher concentrations of polymer in the reaction mixture (0.5-2% w/v) resulted in the formation of aggregates, whereby several silica nanoparticles are bridged together with macromolecules of hydroxyethylcellulose. A correlation was identified between the aggregate size and number of particles per aggregate based on size discrepancies observed between DLS and SANS measurements. This information makes it possible to control the size of aggregates during a simple one-pot synthesis; a prospect highly desirable in the design of potential drug delivery systems.
近年来，用聚合物对纳米颗粒进行功能化处理备受关注，因为它有助于胶体稳定性和表面性质的调控。在此，通过3-巯丙基三甲氧基硅烷在羟乙基纤维素存在下的自缩合反应合成了聚合物包覆的硫醇化二氧化硅纳米颗粒。这些纳米颗粒通过动态光散射、小角中子散射、纳米颗粒跟踪分析、拉曼光谱、傅里叶变换红外光谱、热重分析、埃尔曼法、透射电子显微镜和低温透射电子显微镜进行了表征。结果发现，增加反应混合物中羟乙基纤维素的量会增加纳米颗粒的尺寸，并减少其表面硫醇基团的数量。此外，通过利用小角中子散射和动态光散射，证明反应混合物中较高浓度的聚合物（0.5 - 2% w/v）会导致聚集体的形成，即几个二氧化硅纳米颗粒与羟乙基纤维素大分子桥连在一起。基于动态光散射和小角中子散射测量之间观察到的尺寸差异，确定了聚集体尺寸与每个聚集体中颗粒数量之间的相关性。这些信息使得在简单的一锅法合成过程中控制聚集体的尺寸成为可能；这在潜在药物递送系统的设计中是非常理想的前景。
