EDTA-Capped Iron Oxide Core-Corona System as Vehicle for Gene Delivery to Transform E.coli: Mimicking the Lipid Bilayer Environment

EDTA-capped iron oxide nanoparticles (Fe3O4/edta NPs) were synthesized by simple wet chemical method and encapsulated with amphiphilic triblock copolymer Pluronic (R) F127 (Fe3O4/edta/P). The resulting 'core-corona' system becomes capable of condensing plasmid DNA (pDNA) and act as vehicle for cell transformation. As a proof-of-concept, E.coli_DH5 alpha bacterial strain was selected. The plasmids like pBSKS and pUC18 having antibiotic resistance marker gene were eluted from the bacterial strain, purified and loaded on the synthesized nano-assembly. Green fluorescence protein tag was attached to pTX (pTXgfp) to confirm successful transformation. The gene transformation efficiency (TE) of the developed Fe3O4/edta/P vehicle was compared with traditional CaCl2 mediated transformation as a positive control and naked pTXgfp was used as a negative control. PEGlation of Fe3O4/edta was also carried out and the TE of the resulting system was compared with as-synthesized Fe3O4/edta/P. This study demonstrates that Pluronic (R) F127 polymeric surfactant can be used to form stealth surface of the nanocarrier to solve Polyethylene Glycol (PEG) dilemma. The probable mechanism to explain the bacterial cell transformation is discussed.