Abstract：Objective To prepare florfenicol nanocrystals (FF-NC) and evaluate its pharmaceutical properties
in vitro by increasing water solubility of florfenicol (FF). Methods The miniaturized medium grinding method
was adopted, with the vial as the grinding chamber, the zirconia beads as the grinding medium, and the magnetic
stirrer as the power device to construct the FF-NC, with the particle size and polydispersity index (PDI) as the index.
The optimized formulation and process parameters obtained from the test were further amplified and spray-dried
to cure FF-NC (FF-NC). The obtained nanocrystals were characterized by differential scanning calorimetry, X-ray
diffraction and Fourier transform infrared spectroscopy. The saturated solubility and cumulative release in vitro were
evaluated. Results The FF-NC prepared by the optimal formulation and process of orthogonal test had a particle
size of (189.6±3.44)nm and a PDI of (0.192±0.021). The particle size of FF-NC after redissolution was basically the
same as that before spray drying. X-ray diffraction pattern and differential scanning calorimetry results showed that
FF was amorphous after being prepared into nanocrystals. The results of in vitro dissolution showed that the prepared
FF-NC had significantly higher saturation solubility and cumulative dissolution in vitro than FF. Conclusion The
miniaturization media grinding method provides a simple and effective way for the screening of FF-NC, and provides a
basis for the preparation of bulk release. The rapid release and high efficiency of FF-NC obtained from the preparation
are worthy of further study.