Enzyme-free isothermal amplification strategy for the detection of tumor-associated biomarkers: A review

The detection of tumor-associated biomarkers contributes to personalized precision medical treatment of cancer patients in early stage. Combined with nucleic acid amplification technology, DNA has been used as a fascinating biomaterial for assembling artificial reaction networks and detecting biomarkers due to its inherent biocompatibility and programmability. Compared with polymerase chain reaction and enzyme-mediated isothermal nucleic acid amplification techniques, enzyme-free amplification strategy are more ideal signal amplification methods, which is of great value for the development of low-cost and more robust point-of-care-testing without the restriction of thermal cyclers. To date, based on TMSD reaction and precise probe design, they have been widely used in biological analysis. In this review, we first introduce the basic principles and advanced techniques of enzyme-free amplification strategies. Then, we discuss the typical application of enzyme-free amplification strategies in the detection of tumor-associated biomarkers. Finally, the challenges and future prospects are proposed.