Preparation of 5-Fluorouracil Loaded Polylactide-co-glycolide-co-methoxy Poly（ethylene glycol） （PLGA-mPEG） Nanoparticles via High Speed Shearing

5-Fluorouracil（5-FU） loaded nanoparticles（NPs） were prepared by a high speed shearing double emulsion method with polylactide-co-glycolide-co-methoxy poly（ethylene glycol）（PLGA-mPEG） as loading material. The prepared NPs possess a negative zeta potential and their loading efficiency is about 15%（mass fraction）. The result of in vitro release shows that the release behavior of 5-FU from NPs is coincident with Zero-level release from the second day.     

Development of NAMI-A-loaded PLGA-mPEG Nanoparticles: Physicochemical Characterization,in vitro Drug Release and in vivo Antitumor Efficacy

NAMI-A has showed extraordinary activities against metastatic tumors. However, the hydrolysis of DMSO from NAMI-A could reduce anti-metastatic activity. To enhance the circulation time and the anti-metastatic effect of NAMI-A, we first synthesized the NAMI-A-loaded nanoparticles. NAMI-A-loaded nanoparticles were prepared by the double emulsion method and characterized by scanning electron microscopy for surface morphology, laser light scattering for size and zeta potential for surface charge. Controlled release of NAMI-A was observed in a sustained manner. Compared with free NAMI-A, NAMI-A -loaded nanoparticles exhibited superior antitumor effect by delaying tumor growth in T739 mice. PLGA-mPEG nanoparticles are promising for further studies as drug delivery carriers.     

A detailed view of PLGA-mPEG microsphere formation by double emulsion solvent evaporation method

PLGA, m PEG diblock copolymer was synthesized by bulk ring-opening polymerization method. The double emulsion solvent evaporation method was used to prepare bovine serum albumin(BSA)-loaded microspheres. Optical microscopy was used to observe the whole microsphere fabrication process. It is confirmed that the proportion of inner aqueous phase is one of the most critical factors that determines the morphology of microspheres. Double emulsion droplets which have appropriate amount of inner aqueous phase can form closed and dense microspheres, while, too much inner aqueous phase will cause a collapse of the double emulsion droplets, resulting in a loss of drug. The proportion of inner aqueous phase was varied to prepare microspheres of different morphology. The results show that with increasing the amount of inner aqueous phase, a higher percent of broken microspheres and lower encapsulation efficiency appeared, and also, a more severe initial burst release and faster release rate.