Probing DNA structure with nanoparticles.

: Semiconductor nanoparticles, also known as quantum dots, are receiving increasing attention for their biological applications. These nanomaterials are photoluminescent and are being developed both as dyes and as sensors. Here we describe our "sensor" use of quantum dots to detect different intrinsic DNA structures. Structural polymorphism in DNA may serve as a biological signal in vivo, highlighting the need for recognition of DNA structure in addition to DNA sequence in biotechnology assays.