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Guangzhou, China

Qin L.,Sun Yat Sen University | Qin L.,Guangdong Research Center for Drug Delivery Systems | Mei L.,Sun Yat Sen University | Shan Z.,Sun Yat Sen University | And 6 more authors.
Drug Development and Industrial Pharmacy | Year: 2016

Phytantriol has received increasing amount of attention in drug delivery system, however, the ability of the phytantriol based liquid crystal as a novel embolic agent to provide a sustained release delivery system is yet to be comprehensively demonstrated. The purpose of this study was to prepare a phytantriol-based cubic phase precursor solution loaded with anticancer drug hydroxycamptothecine (HCPT) and evaluate its embolization properties, in vitro drug release and cytotoxicity. Phase behavior of the phytantriol-solvent-water system was investigated by visual inspection and polarized light microscopy, and no phase transition was observed in the presence of HCPT within the studied dose range. Water uptake by the phytantriol matrices was determined gravimetrically, suggesting that the swelling complied with the second order kinetics. In vitro evaluation of embolic efficacy indicated that the isotropic solution displayed a satisfactory embolization effect. In vitro drug release results showed a sustained-release up to 30 days and the release behavior was affected by the initial composition and drug loading. Moreover, the in vitro cytotoxicity and anticancer activity were evaluated by MTT assay. No appreciable mortality was observed for NIH 3T3 cells after 48 h exposure to blank formulations, and the anticancer activity of HCPT-loaded formulations to HepG2 and SMMC7721 cells was strongly dependent on the drug loading and treatment time. Taken together, these results indicate that phytantriol-based cubic phase embolic gelling solution is a promising potential carrier for HCPT delivery to achieve a sustained drug release by vascular embolization, and this technology may be potential for clinical applications. © 2015 Taylor & Francis. Source

Qin L.-Z.,Sun Yat Sen University | Qin L.-Z.,Guangdong Research Center for Drug Delivery Systems | Zhang X.,Sun Yat Sen University | Wu L.-N.,Sun Yat Sen University | And 5 more authors.
Yaoxue Xuebao | Year: 2014

The purpose of this study is to investigate the preparation of hydroxycamptothecine (HCPT)-loaded cubic crystal liquid embolic precursor solution, and evaluate its in vitro embolic efficiency. Phytantriol was used as cubic crystal liquid embolic material, and the optimal formulation was selected according to ternary phase diagram. Polarized light microscopy, differential scanning calorimetry, and small angle X-ray scattering (SAXS) were used to characterize the cubic crystal structure. High performance liquid chromatography and X-ray diffraction analysis were used to investigate the lactone ring of HCPT. In vitro dissolution was preliminary evaluated, and the simulation embolic model was constructed to evaluate the embolic efficiency of precursor solution. Meanwhile, the gelation time and adhesion force were investigated. The results showed that HCPT-loaded precursor solution for embolization had been successfully prepared with low viscosity which was injectable. The precursor solution could transform into Pn3m structure liquid crystal phase gel rapidly when contracting with excess water. The formed HPCT gel remained its lactone form as the same in precursor solution, and expressed the good ability to block the saline flow, and HCPT could keep sustained releasing drug over 30 days. The prepared drug-loaded embolic precursor solution showed a promising potential for vascular embolization and application in clinical treatment of tumor. Source

Huang D.,Sun Yat Sen University | Wang L.,Sun Yat Sen University | Dong Y.,Sun Yat Sen University | Pan X.,Sun Yat Sen University | And 3 more authors.
European Journal of Pharmaceutics and Biopharmaceutics | Year: 2014

This study was designed to investigate the feasibility of silk fibroin nanoparticles (SFNs) for sustained drug delivery in transscleral ultrasound. Fluorescein isothiocynate labeled bovine serum albumin (FITC-BSA, MW 66.45 kDa) was chosen as a model macromolecular protein drug and SFNs were used as nano-carrier systems suitable for ocular drug delivery. Drug loaded nanoparticles (FITC-BSA-SFNs) were first prepared and characterized. In vitro transscleral study under ultrasound exposure (1 MHz, 0.5 W/cm2, 5 min continuous wave) using isolated sclera of rabbit was performed. The posterior eye segment of rabbit was examined for adverse effect by slit-lamp and histology. It was found that FITC-BSA-SFNs possessed sustained release, bioadhesive, and co-permeation characteristics. The ultrasound application significantly improved the penetration efficiency of FITC-BSA-SFNs as compared with passive delivery, meanwhile caused no damages to the ocular tissue and particles themselves. The distribution profile of SFNs revealed rapid and lasting adhesion on the outer scleral tissues, followed by migration into the interior up to one week after treatment. This research suggested a novel non-invasive transscleral administration of macromolecular protein drugs using SFN carriers combining with ultrasound technology. © 2014 Elsevier B.V. All rights reserved. Source

Zhu C.,Sun Yat Sen University | Huang Y.,Sun Yat Sen University | Zhang X.,Sun Yat Sen University | Mei L.,Sun Yat Sen University | And 3 more authors.
Colloids and Surfaces B: Biointerfaces | Year: 2015

The purpose of this study was to compare the properties of exenatide-loaded poly (D,L-lactic-co-glycolic acid) microparticles (Ex-PLGA-MPs) prepared by a novel ultra-fine particle processing system (UPPS) and spray drying. UPPS is a proprietary technology developed by our group based on the disk rotation principle. Characteristics of the MPs including morphology, particle size distribution, drug content, encapsulation efficiency and in vitro release were comparatively studied. Cytotoxicity of the MPs was examined on A549 cells and the pharmacodynamics was investigated in vivo in type 2 diabetes Sprague-Dawley (SD) rats. Ex-PLGA-MPs prepared by UPPS showed larger particle size, denser surface, greater encapsulation efficiency, less initial burst release, and stable sustained release for more than one month in vitro as compared with the spray drying MPs. Meanwhile, the UPPS MPs effectively controlled the body growth rate and blood glucose in diabetes rats for at least three weeks after a single injection, while the spray drying MPs showed effective control period of about two weeks. UPPS technology was demonstrated to manufacture Ex-PLGA-MPs as a potential sustained release protein/polypeptide delivery system, which is an alternative method for the most commonly used spray drying. This comparative research provides a new guidance for microparticle preparation technology. © 2015 Elsevier B.V. Source

Ji J.,Sun Yat Sen University | Zhang J.,Sun Yat Sen University | Chen J.,Sun Yat Sen University | Wang Y.,Sun Yat Sen University | And 6 more authors.
Food Hydrocolloids | Year: 2015

The purpose of this research was to prepare emulsions stabilized by mixed proteins to achieve excellent storage stability and superior functional properties. The emulsions (O/W) with uniform nanoscale droplets (~250 nm, polydispersity index < 0.2) were stabilized by mixed sodium caseinate (SC) and soy protein isolate (SPI) and produced through high pressure homogenization. Characteristics of the emulsions were evaluated by Dynamic Light Scattering (DLS), Nanoparticle Tracking Analysis (NTA), Transmission Electron Microscopy (TEM), Rheometer and Turbiscan Lab analyzer. The stabilization mechanism was preliminarily investigated by studying the influences of pH, NaCl and SDS solutions on the droplet size, with the application of sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE). It was found that both flexible protein SC and rigid globular protein SPI were adsorbed on the oil-water interface while some free protein molecules dissolved in the aqueous phase. Electrostatic repulsion and steric stabilization were contributed to the system stability. The retention ratio of vitamin A palmitate was above 93% after three months of storage at room temperature, which demonstrated the protection efficiency of the emulsion was excellent. This work showed a significant promise to develop nutritional products with satisfactory storage stability and physiological benefits. © 2015 Elsevier Ltd. Source

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