ELECTROLYTIC AGGREGATION IN SOLUTIONS WITH QUANTUM DOTS AND GOLD NANOPARTICLES MODIFIED WITH OLIGONUCLEOTIDES

Abstract

Aim. To investigate electrolytic aggregation of different nano-objects in solutions with quantum dots (QDs) and Au nanoparticles (NPs) modified by oligonucleotides as well as the effect of aggregates on the photoluminescence (PL) of QDs. Methods. Au NPs and AgInS2/ZnS QDs were modified by oligonucleotides. Two types of QDs that differ in size and stabilizing ligand were used. PL and optical absorption of nano-objects in water and SSC buffer solutions were studied. Results. The transfer of modified by oligonucleotides QDs from water to a buffer solution and the addition of Au NP modified by oligonucleotides to the solution caused quenching of the QD PL intensity. The PL quenching was observed for the QDs of two types and increased during the incubation of solutions, but didn’t depend on its multiplicity. An aggregation of Au-DP occurred only in buffer solutions with QDs of one type and increased with multiplicity of the buffer solution. Conclusion. It is found that the electrolytic aggregation of Au NPs modified by oligonucleotides in buffer solutions with QDs depends on the QD type and didn’t affect the quenching of the PL intensity of the QDs.