Parallel Synthesis and Quantitative Structure–Activity Relationship (QSAR) Modeling of Aminoglycoside-Derived Lipopolymers for Transgene Expression

We describe the parallel synthesis of lipopolymers generated by conjugating alkanoyl chlorides to polymers derived from aminoglycoside antibiotic monomers as novel vehicles for transgene delivery and expression in mammalian cells. Parallel screening of lipopolymers led to the identification of six leads that demonstrated higher transgene expression efficacies in several cancer cells, when compared to the parental polymers as well as 25 kDa poly­(ethylene imine), a current standard for polymer-mediated transgene expression. Quantitiative structure–activity relationship (QSAR)-based cheminformatics modeling was employed in order to investigate the role of lipopolymer physicochemical properties (molecular descriptors) on transgene expression efficacy. The predictive ability of the QSAR model, investgated using lipopolymers not employed for training the model, demonstrated excellent agreement with experimentally observed transgene expression. Our findings indicate that lipid substitution on aminoglycoside-derived polymers results in high levels of transgene expression compared to unsubstituted polymers. Taken together, these materials show significant promise in nonviral transgene delivery with several applications in biotechnology and medicine

Aminoglycoside Antibiotic-Derived Anion-Exchange Microbeads for Plasmid DNA Binding and in Situ DNA Capture

Plasmid DNA (pDNA) therapeutics are being investigated for gene therapy and DNA vaccines against diseases including cancer, cystic fibrosis and AIDS. In addition, several applications in modern biotechnology require pDNA for transient protein production. Here, we describe the synthesis, characterization, and evaluation of microbeads (“Amikabeads”) derived from the aminoglycoside antibiotic amikacin for pDNA binding and in situ DNA capture from mammalian cells. The parental aminoglycoside-derived microbeads (Amikabeads-P) acted as anion-exchange materials, and demonstrated high capacities for binding pDNA. Binding of pDNA was significantly enhanced following quaternization of the amines on the microbeads (Amikabeads-Q). Amikabeads were further employed for the disruption and extraction of DNA from mammalian cells, indicating their utility for in situ DNA capture. Our results indicate that Amikabeads are a novel material, with multiple reactive groups for further conjugation, and can have several applications in plasmid DNA biotechnology