Semiconductor quantum dots (QDs) and metal nanoparticles (NPs) have attracted a great deal of attention in the biology community due to their application as fluorescent labels and sensors. The optical properties of NPs allow them to be effective imaging agents for biomolecules. Their biological sensing abilities include identifying target DNA through a linker, followed by color change and electrical signaling. However, size-controlled NPs have the potential to be used as more than just sensors and labels. In order to develop novel applications of NP-biomolecule complex, an understanding of the fundamental interactions between them is critically important. To date, most NP-DNA complexes have been made through linker; i.e., the NPs are attached with DNA via an intermediary molecular link, either functionalized on the surface of NPs or with DNA, or both. The goal of this research is to determine the nature of fundamental interactions that occur directly between NPs and DNA.