明胶纳米颗粒的制备

Preparation of Gelatin Nanoparticles

以B型明胶为原料,戊二醛为交联剂,通过改进的两步去溶剂法制备了较小粒径(约100 nm)的明胶纳米颗粒(Gelatin nanoparticles,GNPs),考察了分散体系浓度、去溶剂化试剂、交联剂用量对GNPs粒径的影响。结果表明:降低明胶在二次分散体系中的浓度,制得的GNPs的尺寸更小且分布均匀。残留的去溶剂化试剂丙酮需去除,因为它会使GNPs分散性变差。在明胶质量浓度为8 g/L的分散液中,当戊二醛加入量为4.5%(以明胶的质量为基准,下同)时,即可制得稳定的GNPs,其粒径为50~150 nm,PDI约为0.14,Zeta电位绝对值大于30 m V。AFM和TEM测试结果表明:GNPs呈光滑球形,为边缘部分比核心更为疏松的非均质结构。

Gelatin nanoparticles（GNPs,about 100 nm in diameter） were prepared by using type B gelatin as raw material,glutaraldehyde as crosslinking agent by a modified two-step desolvation process.The effects of the gelatin concentration in dispersion solution,desolvation solvent（acetone）,and the amount of the cross-linker（glutaraldehyde） on the particle size of GNPs were also investigated. The results showed that the GNPs with a smaller particle size and uniform distribution can be obtained by reducing the content of gelatin in the second dispersed solution before crosslinking. Moreover,the residual acetone in the as-prepared dispersion must be removed completely. Otherwise,it can lead to poor distribution of GNPs. Stable GNPs were obtained（diameter of 50 ~ 150 nm,polydispersity index of about 0. 14,and Zeta potential 30mV） when the dosage of glutaraldehyde was 4. 5%（based on mass of gelatin） in 8 g/L gelatin dispersion. The results from atomic force microscope（AFM） and transmission electron microscope（TEM） showed that the as-prepared GNPs exhibited spherical morphology with a smooth surface. Additionally,the edge part of heterogeneous sphere was looser than the core.