Surface Deposition and Coalescence and Coacervation Phase Separation Methods: In Vitro Study and Compatibility Analysis of Eudragit RS30D, Eudragit RL30D, and Carbopol-PLA Loaded Metronidazole Microspheres

Figure 1

It schematically presents the steps of microspheres prepared by coacervation phase separation method.

(a) Gelatin-Carbopol/PLA mixture was prepared

(b) Drug-polymer dispersion was prepared

(c) Drug-polymer dispersion was added dropwise to sunflower oil

(d) Formaldehyde was added and stored in refrigerator for 24 hours for rigidization

(e) Finally microspheres are stored in airtight container

(f) Flow diagram of coacervation method