A novel DNA-based nanostructure for single molecule detection purposes

Recently, interest in DNA?nanoparticle hybrid structures synthesis for developing nanoscale assemblies with innovative diagnostics, optical and magnetic properties, all combined in one single nanostructure, is increasing. In other words, nanostructures, which show fluorescent and magnetic features simultaneously, are of particular interest for diagnostics objectives, especially genetic research applications. In this work, we report the synthesis of a magnetic?fluorescent DNA-based dumbbell nanostructure with different size nanoparticles. The DNA dumbbell was made by combining a number of biological tools such as filling, digestion and protein?ligand interaction and visualised by fluorescence microscopy after molecular combing, then proved by AFM using tapping mode. The method described herein provides a new tool and view for making and designing controlled DNA-based nanostructure, which offers more perspectives in the nanomanipulation of single molecules for diagnostics purposes, such as creating barcode labels.