DNA Mimic Foldamer Recognition of a Chromosomal Protein.

Helical aromatic oligoamide foldamers bearing anionic side chains that mimic the overall shape and charge surface distribution of DNA were synthesized. Their interactions with chromosomal protein Sac7d, a non-sequence-selective DNA-binder that kinks DNA, were investigated by Surface Plasmon Resonance (SPR), Isothermal Titration Calorimetry (ITC), Circular Dichroism spectroscopy (CD), melting curve analysis, Atomic Force Microscopy (AFM), and Nuclear Magnetic Resonance (NMR), as well as by single crystal X-ray crystallography. The foldamers were shown to bind to Sac7d better than a DNA duplex of comparable length.

Aptamer melting biosensors for thousands of signaling and regenerating cycles.

Due to their recognition abilities and inherent regenerability, aptamers have great potential in biosensing applications. However, effective signal transduction and regeneration strategies are still required. Herein, we develop a melting-based aptamer sensing strategy capable of homogeneous signaling with over 1000 regenerating cycles without significant deterioration of performance.

Single-molecule dynamic structural biology with vertically arranged DNA on a fluorescence microscope.

The intricate interplay between DNA and proteins is key for biological functions such as DNA replication, transcription and repair. Dynamic nanoscale observations of DNA structural features are necessary for understanding these interactions. Here we introduce graphene energy transfer with vertical nucleic acids (GETvNA), a method to investigate DNA-protein interactions that exploits the vertical orientation adopted by double-stranded DNA on graphene.

Engineering modular and tunable single-molecule sensors by decoupling sensing from signal output.

Biosensors play key roles in medical research and diagnostics. However, the development of biosensors for new biomolecular targets of interest often involves tedious optimization steps to ensure a high signal response at the analyte concentration of interest. Here we show a modular nanosensor platform that facilitates these steps by offering ways to decouple and independently tune the signal output as well as the response window.