Preparation and Evaluation of Thermosensitive Nanocarrier
|Keywords||Poloxamer Chitosan Polymeric micelles Macrophages Dendritic cells|
Objective: To investigate the cationic and temperature sensitivity poloxamer chitosan the graft Nanomicelles physical and chemical properties, and to explore the factors that affect the model antigen uptake by macrophages and dendritic cells, in order for the new The study provides experimental evidence of vaccine carrier. Experimental Methods: The study using 1 - ethyl - 3 - (3 - dimethylamino propyl) - carbodiimide (EDC) and N-hydroxy succinimide (NHS) mediated reaction - Synthesis poise Luo Shamrock - chitosan grafted intermediates and the structure of the product was verified by nuclear magnetic resonance spectra (1H-NMR) and infrared spectra (FT-IR). Using the fluorescent probe method and visible spectrophotometry graft of the critical micelle concentration (CMC) and lower critical solution temperature (LCST). Prepared by directly dispersing polymer nano micelles containing OVA BCA assay Nanomicelles drug loading and encapsulation efficiency, particle size, drug loading and encapsulation efficiency as indicators screening process prescription. To explore Nanomicelles vitro release behavior under conditions of 37 ° C and 4 ℃, visits poloxamer chitosan graft cytotoxicity by MTT assay. Vitro mouse bone marrow mononuclear cells induced to differentiate into dendritic cells, macrophages, and dendritic cell uptake of nanoparticles investigated by fluorescence microscopy and flow cytometry. Experimental results: the IR and NMR analysis confirmed the synthesis of intermediates and poloxamer chitosan graft, thermal analysis results further verify the formation of the poloxamer chitosan graft. When Poloxamer CS dosing quality than 0.63:0.025, obtained polymer CMC value (3.24 ± 0.06) × 10-6 mol L-1, LCST near 37 ℃. In the preferred nanometer micelles Preparation and formulation conditions, the particle size of the prepared drug-loaded nano-micelle (219.1 ± 2.3) nm OVA encapsulation efficiency and drug loading (42.2 ± 5.6)%, respectively, and ( 21.4 ± 2.3)%, and good reproducibility. Zeta-potential drug-loaded nano-micelles (11.67 ± 2.25) mV. Load OVA micelle 4h cumulative release at 37 ℃ for 30%, 4 h at 4 ℃ can be achieved by the release of completely. MTT assay showed low cytotoxicity of polymer micelles. Fluorescence microscopy and flow cytometry results showed that FITC-OVA uptake rate was significantly higher than that of macrophages and dendritic cells FITC-OVA nano-micelle solution state. Conclusions: Poloxamer grafted chitosan nanoparticles formed micelles temperature sensitivity and cationic characteristics, and low cytotoxicity, can significantly increase the load model antigen FITC-OVA antigen presenting cells uptake rate. Micelles to improve Po-CS, targeting dendritic cells for the purpose of monoclonal antibody modified underway.