Frontispiece: DNAzyme Feedback Amplification: Relaying Molecular Recognition to Exponential DNA Amplification

A simple but powerful isothermal DNA amplification method, termed DNAzyme feedback amplification (DFA) capable of relaying molecular recognition to exponential DNA amplification is presented. The method incorporates both an RNA‐cleaving DNAzyme (RCD) and rolling circle amplification (RCA) carried out by a special DNA polymerase using a circular DNA template. This method can be used for the detection of both nucleic acid based targets and non‐nucleic acid analytes. The conceptual framework of the feedback amplification approach, the essential features of this method, and the remaining challenges and possible solutions are discussed on page 4473 ff.