Editor’s Choice – Chitosan Functionalized CuS Nanoparticles Boots Gene Transfection via Photothermal Effect – Current Drug Delivery

Journal: Current Drug Delivery

Author(s): Li Lin, Xiaoda Li, Yongbo Yang, Lijia Jing, Xiuli Yue, Xuzhu Chen, Zhifei Dai


Graphical Abstract:


Background: The lack of smart and controllable gene vectors with high safety and efficiency is still a main obstruction for clinical applications of gene therapy. Recently, the external physical stimuli, such as near infrared light induced temperature elevation, have been applied to enhance the gene transfection efficiency and specificity. The aim of this paper is to fabricate chitosan functionalized CuS nanoparticles (CuS@CS NPs) with small size and higher biocompatibility for enhanced gene delivery by photothermal effect.

Methods: CuS@CS NPs were successfully prepared by simple hydrothermal method. The biocompatibility was detected by MTT method and hymolytic analysis. pEGFP-C1was used as gene model, and its expression efficiency was detected by fluorescence microscopy and flow cytometry to investigate the effect of photothermal effect on the transfection efficiency.

Results: The CuS@CS NPs around 15 nm were successfully engineered. The modification of CuS nanoparticles with chitosan conduced to higher physiological stability and biocompatibility. The utilization of CuS@CS NPs in combination with external near infrared (NIR) laser irradiation could enhance gene transfection efficiency due to photothermal effect. The gene transfection efficiency of CuS@CS NPs found to increase from 5.05±0.54% (0 min) to 23.47±1.27% (10 min), significantly higher than the free polyethylenimine (18.15±1.03%).

Conclusion: CuS@CS NPs showed great capability to control gene delivery by an external NIR laser irradiation and enhance the gene transfection efficiency and specificity because of convenient preparation, stabilized optical properties, excellent photothermal effect and good biocompatibility. It encourages further exploration of the CuS@CS NPs as a photocontrollable nanovector for combined photothermal and gene therapy, as well as image guided therapy.

Read more here: http://www.eurekaselect.com/138394

Article by Disease – “Preparation and Optimization of Moxifloxacin Microspheres for Colon Targeted Delivery Using Quality by Design Approach: In Vitro and In Vivo Study”




Background: Gut microbiota has a significant role in the pathogenesis of diabetes. Colonic microflora modulation using an antibiotic might have an emerging role to treat the metabolic disorders. The present study was aimed to optimize the Moxifloxacin loaded chitosan microspheres (MCMs) by emulsion cross linking method for colon targeted delivery to alter the microflora.

Methods: Preliminary optimization of MCMs was carried out using Placket-Burman design (PBD) following by final optimization with Box-Behnken design (BBD). Optimized MCMs were evaluated for yield, particle size, entrapment efficiency and in vitro/ in vivo antimicrobial activities.

Results: FTIR spectroscopy of MCMs confirms the absence of chemical interactions during the formulation. MCMs were found to be smooth, spherical with particle size around 20μm. An enteric coating of MCMs prevented the drug release in the acidic environment of the stomach and ileum with complete release at the colon. MCMs had followed the korsmeyer – peppas model of drug release, indicating the drug release by non-fickian diffusion pattern. MCMs showed significant in vitro antimicrobial activity against Lactobacillus casei and Escherichia coli. In vivo results of MCMs exhibited prolonged antimicrobial effect of drug in the cecal content of rats. Significant protective activity observed in the ileum and colon histology in rats treated with MCMs compared to the pure drug.

Conclusion: MCMs were formulated by emulsion cross linking method using QBD approach. An enteric coating around the microspheres prevented the premature drug release at upper gastrointestinal tract, while chitosan cross linking has provided the sustain release of the drug in the colonic region over the time.

Read more: http://www.eurekaselect.com/node/142092/article