Synthesis And Performance Of DNA-scaffolded Super-nanoclusters And Their Biological Application

DNA is a kind of biomacromolecule,not only as a genetic material,but DNA is also a perfect candidate from which toassemble such biomaterials due to its biocompatibility,specificity and robust molecular programmability.In recent years,DNA is demonstrated as an ideal scaffold to regulate the formation of silver nanoclusters(AgNCs).DNA scaffolded silver nanoclusters(DNA/AgNC)with optical properties,biocompatibility and small size facilitate a variety of applications such as bioimaging and chemical sensing.Herein,we construct a new DNA nanomaterial.In detail,we use C-rich ssDNA as scaffold to prepare ssDNA/AgNC.We first report design and synthesis Y-shaped DNA(Y-DNA)and further study its structure and morphology.We use Y-DNA as a scaffold to synthesize AgNC(Y-super-DNA)and optimize the sticky-end DNA.At the same time we study effects of Y-DNA and silver ions and AgNC.Using DNA/AgNC fluorescence properties achieved ctDNA detection as its fluorescence property.Then we report the first use of branched DNA as scaffold to regulate the formation of silver nanoclusters(super-AgNC),in which the spatial structures were precisely designed and constructed.We achieved super-AgNC with tunable shapes and arm-lengths including Y-,X-,and(Y-X)-shaped super-AgNC.We systemically studied the molecular structures and optical properties of super-AgNCs.As a proof of application,remarkably,super-AgNCs exhibited superior antibacterial performance.In addition,super-AgNCs showed excellent biocompatibility with three types of tissue cells including 293T(human embryonic kidney cells),SMCs(vascular smooth muscle cells),and GLC-82(lung adenocarcinoma cells).These performances enable our super-AgNCs adaptable in a variety of applications such as biosensing,bioimaging,and antibacterial agents.