Nanocapsules loaded HEMA-based Hydrogel Composites for Drug Delivery

• Main Authors: Liu, Pei-Ling, 劉佩鈴
• Other Authors: Liu, Dean-Mo
• Format: Others
• Language: en_US
• Published: 2011
• Online Access: http://ndltd.ncl.edu.tw/handle/74379955590890371682

碩士 === 國立交通大學 === 材料科學與工程學系 === 99 === Only about 5% of the dose delivered from an eye drop penetrates through the cornea to reach the intraocular tissue, while the rest is lost due to tear drainage. Besides, the dose has a short residence time in the film due to ocular barriers, and the presence of certain drugs in the bloodstream leads to undesirable side effects. In this study, incorporation of amphiphilic chitosan-crystalline silica hybrid macromolecule in a p(HEMA-MAA) hydrogel matrix prepared the particle-laden gels. The chemical structure of this hybrid molecule was characterized by FT-IR and 13C-, 29Si-nuclear magnetic resonance. Amphiphilic nature of the hybrid molecule rendered subsequent self-assembly forming nanocapsules in aqueous solutions. Structural morphology of the hybrid nanoparticles was investigated using scanning electron microscopy (SEM), transmission electron microscopy (TEM). And the mean size of the hybrid macromolecules was characterized by SEM and dynamic light scatter (DLS) measurements which demonstrated a concentration-dependent assembly size. On the other hand, structural morphology of the particle-laden gels was investigated using SEM. And the optical characterization of the particle-laden gels was measured by UV-Vis spectrometer which demonstrated the hybrid nanoparticles have great polydispersion in the polymerizing medium. In term of the drug loading method, according to photosensitivity or water solubility, developed two types of loading method: encapsulation, for non-photosensitive or hydrophobic drugs and impregnation, for photosensitive or hydrophilic drugs. A subsequent application to carry drugs of various degree toward water affinity (from water insoluble, azithromycin (AZM), to water soluble, Vitamin B12, following a controlled drug release in vitro has been systematically investigated. The experimental results indicated a long-term, sustained release profile for both types of drugs were monitored and release kinetics suggested a two-stage profile, suggesting a bimodal release pattern, and has been confirmed to be a result of drug distribution, i.e, within the nanocapsules and inter-capsule regions. Furthermore, the experimental results indicated the drug release behavior influences on hybrid/drug concentration, ambient temperature, pH-value medium, and drug loading method. And, the particle-laden gels showed an outstanding biocompatibility towards the BCE cell line, as well as the commercially lens, ACUVUE, suggest a promising vehicle for ocular drug delivery application.