Programmed biosensors with tunable quantification range and sensitivity would greatly broaden their application in medical diagnosis, food safety and environmental analysis. Herein, we proposed a graphene-nucleic acid biointerface-engineered biosensor, allowing target molecules to be detected with adjustable dynamic ranges and sensitivities. The biosensors were programmed by simply tuning the poly A tail of aptamer probes. The tuning of the poly A tail would allow the interaction between aptamer probes and graphene oxide (GO) to be modulated, in turn programing the competitive binding processes of aptamer probes to target molecules and GO. The biosensors, termed affinity-tunable aptasensors (atAptasensors) could be easily tuned with different dynamic ranges by using aptamer probes with different tail lengths, and the dynamic range could be extended to be over 3 orders by a combined use of multiple aptamer probes. Remarkably, the specificity of aptamer probes could be increased by increasing the interaction between aptamer probes and GO. Reliability of atAptasensor for ATP detection was tested in serum and milk samples, and we also applied atAptasensor for culture-independent analysis of microorganism pollution.

中文翻译：

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具有可调动态范围的石墨烯-核酸生物界面工程生物传感器。

具有定量范围和灵敏度可调的程序化生物传感器将大大拓宽其在医学诊断，食品安全和环境分析中的应用。在这里，我们提出了一种石墨烯-核酸生物界面工程化的生物传感器，允许以可调的动态范围和灵敏度检测目标分子。通过简单地调整适体探针的poly A尾部即可对生物传感器进行编程。调节poly A尾巴将允许调节适体探针和氧化石墨烯（GO）之间的相互作用，进而对适体探针与靶分子和GO的竞争性结合过程进行编程。通过使用具有不同尾巴长度的适体探针，可以轻松地将生物传感器（称为亲和力可调适体传感器（atAptasensors））以不同的动态范围进行调节，结合使用多个适体探针，可以将动态范围扩展到超过3个数量级。值得注意的是，可以通过增加适体探针和GO之间的相互作用来增加适体探针的特异性。在血清和牛奶样品中测试了atAptasensor用于ATP检测的可靠性，我们还将atAptasensor应用于独立于培养物的微生物污染分析。