A method of making a nanoclusters functionalized with a single DNA strand comprising the steps of providing nanoclusters, combining said nanoclusters with thiolated DNA, incubating said nanoclusters and thiolated DNA mixture, combining said mixture with a solution comprising ethanol and dichloromethane; separating said mixture into an aqueous phase and an organic phase, mixing said aqueous phase with a solution comprising dicholormethane and NaCl, and separating the mixture into an aqueous phase and an organic phase; wherein said organic phase comprises said nanoclusters functionalized with a single DNA strand. Further, provided is a nanocluster functionalized with a single DNA strand comprising a nanocluster, said nanocluster being functionalized with a single DNA strand, said DNA strand having a length of about 10 to about 50 bases.