Label free analysis of multiplex analytes is of great demand in modern bio-analytical science. In this study, a novel DNA junction coupled with two different G-quadruplex DNA structures was demonstrated, achieving colorimetric and fluorescent signal report. Upon the introduction of different targets (including DNA and Lysozyme), the specific interaction between targets and sensing DNA junction could induce the reaction of exonuclease-stimulated recycling of target DNA and conformation transformation based on aptamer/lysozyme binding. With the integration of G-quadruplex/Hemin as colorimetric probe and G-quadruplex/PPIX as fluorescence probe, this label-free sensing system showed high sensitivity and selectivity for DNA and lysozyme detection. Furthermore, we also demonstrated that this novel sensing method could respond to these two targets independently and simultaneously, promising a great hope for its potential application in analytical fields.

在现代生物分析科学中，对多种分析物进行无标记分析的需求很大。在这项研究中，展示了一种新颖的DNA连接点，结合了两个不同的G-四链体DNA结构，实现了比色和荧光信号报告。引入不同的靶标（包括DNA和溶菌酶）后，靶标与感测DNA连接之间的特异性相互作用可诱导核酸外切酶刺激的靶标DNA循环反应和基于适体/溶菌酶结合的构象转化。通过整合G-quadruplex / Hemin作为比色探针和G-quadruplex / PPIX作为荧光探针，这种无标记的传感系统对DNA和溶菌酶的检测具有很高的灵敏度和选择性。此外，