Signal amplification strategies for DNA-based surface plasmon resonance biosensors

DNA has well-defined ability to recognize a wide variety of targets, such as small biological molecules, proteins, inorganic ions and small organic molecules. As molecular recognition elements, DNA can be used to build simple, rapid and sensitive biosensors for detection of these targets. DNA-based SPR sensors are considered to be a real-time and label-free tool. We present a systematical and critical review on DNA-based SPR biosensors and their signal amplification via various strategies, focusing on recent advances in nanomaterials, novel DNA amplifications, redox reactions on surface, enzyme amplifications, as well as promising multiplex amplification strategies.