Next generation carbon nanoparticles for efficient gene therapy.

In a pursuit to develop a commercially exploitable and traceable gene delivery vehicle, here, we develop next generation carbon nanoparticle-DNA complex (CNPLex). CNPLexes were used to transfect green fluorescent protein (GFP) reporter gene containing plasmid DNA (pDNA) pEGFP-N1 targeting breast cancer cells MCF-7 and MDA-MB231. Prepared CNPs were optimized for particle size, surface potential, polymer surface decoration, absorbance efficiency, fluorescence efficiency, IR spectroscopic signatures, and DNA loading and release efficiencies. Rigorous biophysical methods were employed to determine the variations in physicochemical properties of CNPs after surface decoration with polymers followed by complexation with pDNA. Optimized CNPLexes were used to deliver pEGFP-N1 plasmid and efficiency of GFP was followed by fluorescence microscopy and quantified by flow assisted cell sorting. Lipofectamine2000 was used as positive control according to manufacturer's protocol and found to be comparative in transfection efficiency with one of our novel formulations. Further evaluation of cell toxicity and cell viability was performed by LDH activity and MTT assay, respectively. It was found that cell toxicity furnished by polymer decorated carbon nanoparticles was significantly low compared to the parent polymer (polyethylenimine, PEI). Similarly cell viability was found to be much higher with CNPLexes compared to PEI alone. This established the developed particles as better transfecting agents for reporter gene plasmid pEGFP-N1 compared to PEI and showed similar efficacy to one of the best known commercial transfection agents Liofectamine2000 in breast cancer cells MCF-7 and MDA-MB231.

A dual strategy for sensing metals with a nano 'pincer' scavenger for in vitro diagnostics and detection of liver diseases from blood samples.

This work presents a dual, non-invasive approach for the detection of elevated level of metals in patients with liver disease. A highly sensitive, small molecule 'pincer' scavenger was synthesized for the detection and quantification of copper in serum and systemically in vivo. For the in vitro diagnostics, the developed technique involves only a routine capillary blood sampling or venipuncture, removing the need for invasive biopsies. The organic scavenger molecule showed high specificity toward copper ions, with a detection sensitivity of 1.35 × 10(-2)µg/L in mouse serum. Furthermore, for the systemic detection of copper in the liver, a polymeric nanopincer has been designed and studied. The small molecule scavengers were stably incorporated into polymeric micelles via its long acyl chains and polymeric micelle proved to be a stable carrier when injected into mice intravenously. The organic scavenger molecule was found to be highly fluorescent and specific toward Cu(2+) and can potentially help ameliorate diseases regarding accretion of copper in certain vital organs. The strategy and the results provide a novel, non-invasive dual nanomedicine approach for the early detection and treatment of excessive metal deposits in the human organs.