Content of adenosine triphosphate (ATP) is an essential index in the development of various diseases and even some malignant tumors. Biosensing for ATP with high sensitivity and accuracy is of fundamental importance in both biological research and medical diagnostics. Here we report a ratiometric fluorescent sensor for ATP based on multi-color silver nanoclusters (Ag NCs). This nanosystem contains two core components: a hairpin DNA integrated with an ATP aptamer, an anchor sequence and a special template segment for synthesis of green-emitting Ag NCs; a single-stranded DNA (ssDNA) which is incompletely complementary with the anchor sequence to be a duplex scaffold for red-emitting Ag NCs. Once exposed to the target, formation of the ATP/aptamer complexes opens the hairpin structure and releases the anchor sequence to hybridize with the ssDNA, accompanied by the “turn-off” of the green fluorescence and “turn-on” of the red fluorescence. By measuring the fluorescence intensity ratio of the two signals, we successfully establish a ratiometric sensor which exhibits sensitive and accurate assay performance toward ATP, with the limit of detection (LOD) as low as 0.38 μM. Meanwhile, this ratiometric sensor shows stable recovery in real sample assay, indicating their potential promise in practical applications.

三磷酸腺苷（ATP）的含量是各种疾病甚至某些恶性肿瘤发展的重要指标。具有高灵敏度和准确性的ATP生物传感在生物学研究和医学诊断中都至关重要。在这里，我们报告基于多色银纳米簇（Ag NCs）的ATP比例荧光传感器。这个纳米系统包含两个核心组成部分：与ATP适体整合的发夹DNA，锚序列和用于合成绿色发光Ag NC的特殊模板片段。与锚序列不完全互补的单链DNA（ssDNA），成为发红光的Ag NCs的双工支架。暴露于靶标后，ATP /适体复合物的形成会打开发夹结构并释放锚序列以与ssDNA杂交，伴随着绿色荧光的“关闭”和红色荧光的“开启”。通过测量两个信号的荧光强度比，我们成功地建立了一种比例式传感器，该传感器对ATP表现出灵敏而准确的测定性能，检测限（LOD）低至0.38μM。同时，这种比例传感器在实际样品分析中显示出稳定的回收率，表明它们在实际应用中的潜在前景。