The Study of Nerve Conduit with Biocompatibility and Electrical Stimulation Effect

Conductive polymers show great promise because of their electrical property based on bioelectricity in vivo. In order to search electro-activity materials which insure abduction of tissue, we synthesized conductive nerve conduits with poly-dl-lactic-acid(PDLLA) and tetra-aniline(TA). Preparation technology of TA was optimized, and the properties of the conduit were studied. RSC96 cell were used to investigate the toxicity and electrical stimulation effect. SD rats were used to assess biocompatibility in vivo. The results showed that the reaction ratio of 1:1, the reaction time of 2 h and the HCl concentration of 2 mol/L were the optimum conditions for synthesis of TA. The influence of TA content on the mechanical properties, hydrophilicity, conductivity and microstructure of the nerve conduit was evaluated. Cell and histocompatibility study showed PDLLA/TA possessed good biocompatibility. These results showed it had application values in tissue projects.

Preparation and Characterization of an Intelligent Multitarget Tracking HA-RGD-CLB-QDs Drug Delivery System

This work aimed to develop an intelligent multi-target tracking hyaluronic acid-RGDchlorambucil-quantum dots（HA-RGD-CLB-QDs） drug delivery system. After deacetylated, hyaluronic acid was reacted with anticancer drug chlorambucil, RGD, and quantum dots to obtain the HA-RGD-CLB-QDs drug delivery system. The characterization by FT-IR, ~1 H NMR, TEM, XPS, DLS, and UV-vis absorption and fluorescence spectra show that the system is successfully constructed with an average particle size of about 70 nm. The results of the drug release profile show that that the system has a p H and enzyme sensitive controlled release behaviour. Moreover, cellular uptake and toxicity results show that the system has an ideal dual receptormediated endocytosis pathway that significantly enhances the efficacy of CLB tumor therapy and has a lower toxicity to normal cells.The system shows the potential application as a carrier for cancer therapy.

Hyaluronic Acid-RGD Peptide Conjugated Mesoporous Silica-coated Gold Nanorods for Cancer Dual-targeted Chemo-photothermal Therapy

A multifunctional drug delivery system（GNRs@mSiO_2-HA-RGD） was developed by conjugating targeting ligand hyaluronic acid（HA） and RGD with mesoporous silica-coated gold nanorods（GNRs@mSiO_2） for dual-targeted chemo-photothermal therapy. The physiochemical properties of the prepared nanoparticles were characterized by FTIR, UV-vis spectra, and ~1H NMR. Doxorubicin hydrochloride（DOX）, an anticancer drug, was used as the model drug to investigate the drug loading, in vitro drug release profiles and cytotoxicity. The experimental results show that DOX-GNRs@mSiO_2-HA-RGD is synthesized with a mean diameter of 116 nm and a sufficient load capacity of about 19.8%. It also has p H-enzyme sensitive and NIRtriggered drug release manner. Cellular uptake indicates that DOX-GNRs@mSiO_2-HA-RGD exhibits a higher cellular uptake via CD44 receptor and integrin receptor mediated endocytosis compared with the GNRs@mSiO_2 modified with one receptor or no receptor. In comparison with chemotherapy or photothermal therapy alone, DOX-GNRs@mSiO_2-HA-RGD displayes the synergistic effects and achieves a higher therapeutic efficacy. It can be expected that DOX-GNRs@mSiO_2-HA-RGD is a potential dual-targeted chemo-photothermal therapeutic platform for effective cancer treatment.