Polyethyleneimine-Coated Gold Nanoparticles: Straightforward Preparation of Efficient DNA Delivery Nanocarriers

• Published in: Chemistry, an Asian journal an Asian journal, 2016-12, Vol.11 (23), p.3365-3375
• Main Authors: Ortega-Muñoz, Mariano, Giron-Gonzalez, M. Dolores, Salto-Gonzalez, Rafael, Jodar-Reyes, Ana Belen, De Jesus, Samantha E., Lopez-Jaramillo, F. Javier, Hernandez-Mateo, Fernando, Santoyo-Gonzalez, Francisco
• Format: Article
• Language: English
• Subjects: Animals; Caveolae - metabolism; Cell Survival - drug effects; Chemistry; CHO Cells; Cricetinae; Cricetulus; Deoxyribonucleic acid; DNA; DNA - chemistry; DNA - metabolism; Drug Carriers - chemistry; Drug Carriers - toxicity; Dynamic Light Scattering; gene delivery; Genetic Vectors - metabolism; gold; Gold - chemistry; Metal Nanoparticles - chemistry; Metal Nanoparticles - toxicity; Microscopy, Electron, Transmission; Microscopy, Fluorescence; microwave chemistry; nanocarriers; Nanoparticles; Polyethyleneimine - chemistry; RNA, Small Interfering - chemistry; RNA, Small Interfering - metabolism; Spectrophotometry, Ultraviolet; Transfection
• ISSN: 1861-4728; 1861-471X
• DOI: 10.1002/asia.201600951

A novel one‐pot method for the synthesis of polyethyleneimine (PEI)‐coated gold nanoparticles (AuPEI‐NPs) that combines the reductant–stabilizer properties of PEI with microwave irradiation starting from hydrogen tetrachloroaurate acid (HAuCl4) and branched PEI 25 kDa (b25kPEI) was explored. The method was straightforward, green, and low costing, for which the Au/PEI ratio (1:1 to 1:128 w/w) was a key parameter to modulate their capabilities as DNA delivery nanocarriers. Transfection assays in CHO‐k1 cells demonstrated that AuPEI‐NPs with 1:16 and 1:32 w/w ratios behaved as effective DNA gene vectors with improved transfection efficiencies (twofold) and significantly lower toxicity than unmodified b25kPEI and Lipofectamine 2000. The transfection mediated by these AuPEI‐NP–DNA polyplexes preferentially used the caveolae‐mediated route for intracellular internalization, as shown by studies performed by using specific internalization inhibitors as well as colocalization with markers of clathrin‐ and caveolae‐dependent pathways. The AuPEI‐NP polyplexes preferentially used the more efficient caveolae internalization pathway to promote transfection, a fact that supports their higher transfection efficiency relative to that of Lipofectamine 2000. In addition, intracellular trafficking of the AuPEI‐NPs was studied by transmission electron microscopy. Fast delivery: Branched polyethyleneimine 25 kDa (b25kPEI)‐coated gold nanoparticles (AuNPs) that behave as efficient nonviral gene vectors are easily prepared in a straightforward manner by a simple, fast, green, and low‐costing microwave (MW)‐assisted novel protocol.