Jizheng Song,Yu Hu,Shiyu Yang,Dexue Liu,Yiider Tseng,Lingjun Li
Hydrophobic modification alters the properties of Pluronic F127 to form micelles more efficiently and enhances its drug-loading capacity. However, selecting the appropriate hydrophobic group for modification is laborious. In this paper, we propose an efficient approach for predicting key parameters to select hydrophobic groups for F127 modification prior to synthesis, in order to improve the formability and stability of the micelles. The results of nuclear magnetic resonance and isothermal titration calorimetry were utilized to establish a function for predicting the hydrophile–lipophile balance, critical micelle concentration, and Gibbs free energy of the products based on the structure of raw material. These predicted values can assist us in selecting suitable hydrophobic groups for F127 modification. Subsequently, we successfully tested our method and validated our work using pharmaceutical evaluation methods, such as appearance observation, particle size measurement, drug loading determination, equilibrium binding rate assessment, storage stability testing, and the plotting of accumulation release curves. Therefore, we suggest that our work could provide a model linking the molecular structure to properties, with the purpose of pre-selecting modification products that have advantages in micelle preparation. This can facilitate the application of F127 in preparing nano-micelles.
Yang Dongyu,Yuan Chaosheng,Yang Kun,Shao Chunguang,Wang Yongqiang,Cheng Xuerui,Su Lei
Isothermal crystallization behavior of Pluronic F127 blended with and without an ionic liquid (IL) was investigated by in situ polarized optical microscopy (POM) and Fourier transform infrared spectroscopy (FTIR). For the pure F127, the POM and FTIR results showed that the spherulite size and crystallinity of F127 increased with the melting temperature increasing to 60, 80, and 135°C. This could be explained by the flexibility of the polymer chain at high melting temperatures. For the F127 blended with IL, the POM results showed that the morphology of F127 evolved from spherulite to dendritic segregation and fibrous crystal with the increasing IL content. FTIR results indicated that hydrogen bonds were formed between F127 and IL, and the intensity of the hydrogen bonds became strengthened gradually with increasing IL content. The effect of hydrogen bonds on the morphology evolution of F127/IL is discussed.