DNA-Conjugated Silver Nanoclusters Encapsulated in Microemulsion Droplets

Abstract

Silver nanoclusters (Ag NCs) coordinated to DNA oligonucleotide molecule in nanowater droplets in emulsion system was studied with the view to determining the possibility of adopting this method in drug delivery systems as well as in medical and allied sciences. DNA oligomer was coordinated to Ag (1) ions in water droplets of microemulsion and then reduced with equimolar portion of sodium borohydride solution in microemulsion. Uv-vis results showed consistency with spectra of scattered water droplets; it also showed the absence of plasmon bands of silver nanoparticles (Ag NPs) which indicates the formation of Ag NCs. Confocal microscopy images displayed evidences of meshed fluorescing samples on silicon wafer in contrast to the control samples. Dynamic light scattering (DLS) spectrum demonstrated that irrespective of the size of the water droplets DNA molecule were encapsulated in the droplets despite their radius of gyration. TEM images showed the formation of dense, globular, spherical micellar mass which underscores the presence of these Ag/DNA globular mesh on holey carbon grid. It was concluded that with the right chemistry and reaction conditions we can direct analyte molecules to target biomolecules in microemulsion systems for diagnostic and therapeutic purposes by adopting similar mechanistic approach presented in this study.