Preparation, characterization of PLGA/chitosan nanoparticles as a delivery system for controlled release of DHA.

In this work, a novel DHA-loaded nanoparticle with PLGA and chitosan (PCSDNP) was successfully prepared. The structure of PCSDNP and DHA-loaded PLGA nanoparticles was measured by transmission electron microscope, scanning electron microscope, and differential scanning calorimeter. The interaction strength between DHA, PLGA, and chitosan was evaluated through Fourier transform infrared spectroscopy. The curves of controlled DHA release and stabilities for different environmental factors of two NPs were evaluated. Importantly, two NPs were almost regularly spherical and the interactions were hydrogen bonds and electrostatic interactions between PLGA and chitosan. These NPs had a good encapsulation rate (80.45%) and high-water solubility than the free DHA molecule. In simulated gastrointestinal fluid, two NPs showed a controlled-release pattern. Overall, PCSDNP had better stability and controlled-release effect with the synergy between CS and PLGA under the conditions of pH (2- 7), ionic strength (0- 500 mM), storage time (0- 42 d), and temperature (30- 80 °C).