Résumé
Objective: To prepare the epigallocatechin-3-gallate (EGCG) chitosan nanoparticles (CS-NPs) and investigate their physicochemical properties. Methods: The EGCG-CS-NPs were prepared by ion gelation method. The formulation variables were optimized by Box-Behnken Design (BBD) of response surface methodology (RSM) of CS concentration (X1), sodium tripolyphosphate concentration (X2), and EGCG concentration (X3) as independent variables and encapsulation efficiency (Y1,%) and particle size (Y2, nm) as dependent variables. The optimized CS-NPs were characterized for encapsulation efficiency (EE), particle size, Zeta potential, morphology, and in vitro drug release behavior of EGCG-CS-NPs were studied. Results: An optimal EGCG-CS-NPs consisting of CS concentration as 2.6 g/L, sodium tripolyphosphate concentration as 1.5 g/L and EGCG concentration as 2.7 g/L. For EE, particle size, Zeta potential of EGCG-CS-NPs were found to be (85.8±3.1)%, (102.2±27.1) nm, and (25.5±4.1) mV, respectively. The CS-NPs were found to be small and spherical as seen in transmission electron microscopy (TEM). The in vitro release data proved that the drug release was steady within 24 h (pH 4.5 PBS). Conclusion: Through optimizing the formulation, we obtain the uniform EGCG-CS-NPs with in vitro sustained-release behavior. This work is useful for the further research on pharmacodynamics of EGCG-CS-NPs.
Résumé
Objective: Optimization of ginkgolides components (GC) self-microemulsifying drug delivery system (SMDDS) (GC-SMDDS) and similarity analysis on each drug release. Methods: Using equilibrium solubility to screen the oil phase, emulsifier, and co-emulsifier; Taking appearance, the proportion of microemulsion particle size, Zeta potential, surfactants and co-surfactants, and surfactant mixing ratio of the oil phase as study factors, pseudo-ternary phase diagrams were used to screen GC-SMDDS process. SMEDDS of drug loading, particle size distribution, Zeta potential, and stability were evaluated. With the aid of the similarity factor and the curve linear regression slope analysis, the similarity between the composition of the component and the rate and extent of drug release was analyzed. Results: Optimal prescription of polyoxyethylene and polyethylene glycol 200 mass ratio of 4:1, ethoxylates and polyethylene glycol quality and bitterness total mass of 200 capric triglycerides ratio of 9:1, drug content of 100 mg/g. Particle size under 40 nm, ginkgolides 48 h internal components from microemulsion to room temperature, high temperature, and low temperature stability is good. The release quantity achieves the synchronous drug release with the similarity of 96.9%. Conclusion: The SMDDS not only can improve the dissolution of difficult soluble drugs, but also independently regulate the drug release behavior of each component so as to make the drug release maintain good consistency.