| Summary: | 碩士 === 國立臺灣科技大學 === 醫學工程研究所 === 101 === This study demonstrates the feasibility of using a single- capillary electrospray (ES) system to generate novel alpha-lipoic acid (ALA) encapsulated poly(ethylene oxide)-chitosan, and tea tree oil (TTO) encapsulated poly(vinylpyrrolidon)-chitosan (ALA-PEO-CS and TTO-PVP-CS) particles with monodispersed diameters. Scanning electron microscopic images (SEM) and dynamic light scattering (DLS) results indicate that the ES system can generate either a dry powder or a homogeneous water-based suspension of ALA-PEO-CS and TTO-PVP-CS particles. The SEM images revealed that both ALA-PEO-CS and TTO-PEO-CS particles have spherical shape with diameters of approximately 707 ± 66.68 nm, and 659.8 ± 229.0 nm. In addition, zeta potential studies were performed using a zetasizer instrument and showed positively electric surface potential of 57.7 ± 0.5 mV of ALA-PEO-CS , and almost neutral -4.1±0.01 mV of TTO-PVP-CS. Based on the zeta potential studies, we concluded that the excellent dispersity and stability of ALA-PEO-CS and TTO-PVP-CS suspension is attributed to the reduction in particle size and electrostatic repulsion between these submicron particles. Besides, TTO no longer suffered from its poor solubility in drug evaluation, because of the result above. Finally, we used lipopolysaccharide (LPS)-induced nitrite formation in Raw 264.7 macrophages as a model for in vitro anti-inflammation evaluation. We find that the anti-inflammatory ability of the ALA-PEO-CS particles is superior to that of free ALA solution in macrophage cells, which is attributed to the more efficiently intracellular delivery. The confocal image results proved that the uptake of ALA-PEO-CS particles by the LPS-treated Raw 264.7 macrophages is possibly initiated by the interaction with cell-surface molecules through electrostatic interactions, followed by endocytosis of the attached particles. TTO, also showed good anti-inflammatory effect in LPS test, which is attributed to all the effective components were carried in the carriers. We believe that ALA-PEO-CS and TTO-PVP-CS have great potential as novel formulation for anti-inflammatory treatment.
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