The advantages of rapid amplification of nucleic acid without a template based on terminal deoxyribonucleotidyl transferase (TdT) have been widely used in the field of biosensors. However, the catalytic efficiency of TdT is affected by extension conditions. The sensitivity of TdT- mediated biosensors can be improved only under appropriate conditions. Therefore, in this review, we provide a comprehensive overview of TdT extension characteristics and its applications in biosensors. We focus on the relationship between TdT extension conditions and extension efficiency. Furthermore, the construction strategy of TdT-mediated biosensors according to five different recognition types and their applications in targets are discussed and, finally, several current challenges and prospects in the field are taken into consideration.
Keywords: Terminal deoxyribonucleotidyl transferase; biosensor; catalytic efficiency; extension conditions; recognition types; sensing strategy.
Brief introduction to terminal deoxyribonucleotidyl transferase (TdT) characteristics.Provided a systematic and comprehensive summary of TdT extension conditions.Summarized the four effect factors of catalytic efficiency based on extension conditions and enzyme conformation.Sensing strategies of TdT-mediated biosensors for five different recognitions were summarized in detail.The applications of TdT-mediated biosensors in six targets were introduced in detail.