Short DNA molecules are chemically tethered to metal microelectrodes at one end. When applying AC voltages to the electrodes, the DNA molecules are repelled from -or attracted to- the surface. This molecular switching is monitored in real time by optical means. Receptors attached to the DNAs' upper ends serve as capture sites for target molecules. Label-free targets which bind to the interface alter the switching behavior, and 'classical' binding parameters (K_D, k_on, k_off) can be analyzed.

Unprecedented for a biochip detection platform, a molecular dynamics measurement yields additional information which is used to analyze the target molecule size and shape.

switchSENSE at a glance

» label-free, real-time 
    → quantitative analysis of k_on, k_off, K_D

» highly sensitive 
    → fM target concentrations

» microarray 
    → suitable for high-throughput screening

» unique molecular dynamics measurement on chip 
    → analysis of target size/shape