By analogy to the revolution the "home glucose monitor" created in the treatment of diabetes, the availability of a modular, "platform" technology able to measure nearly any metabolite, biomarker, or drug "at-home" in unprocessed, finger-prick volumes of whole blood could revolutionize the monitoring and treatment of disease. Thus motivated, we have adapted here the electrochemical aptamer-based sensing platform to the problem of rapidly and conveniently measuring the level of phenylalanine in the blood, an ability that would aid the monitoring and management of phenylketonuria (PKU). To achieve this, we exploited a previously reported DNA aptamer that recognizes phenylalanine in complex with a rhodium-based "receptor" that improves affinity. We re-engineered this to undergo a large-scale, binding-induced conformational change before modifying it with a methylene blue redox reporter and attaching it to a gold electrode that supports the appropriate electrochemical interrogation. The resultant sensor achieves a useful dynamic range of 90 nM to 7 μM. When challenged with finger-prick-scale sample volumes of the whole blood (diluted 1000-fold to match the sensor's dynamic range), the device achieves the accurate (±20%), calibration-free measurement of blood phenylalanine levels in minutes.

中文翻译：

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使用适用于护理点应用的基于电化学适体的传感器对血液中的苯丙氨酸水平进行免校准测量。

与糖尿病治疗中“家用血糖监测仪”的革命类比，模块化“平台”技术的可用性能够在未经处理的指尖刺血中“在家”测量几乎任何代谢物、生物标志物或药物大量的全血可以彻底改变疾病的监测和治疗。因此，我们在这里采用了基于电化学适体的传感平台来解决快速、方便地测量血液中苯丙氨酸水平的问题，这种能力将有助于苯丙酮尿症 (PKU) 的监测和管理。为了实现这一目标，我们利用了先前报道的 DNA 适体，该适体可识别与铑基“受体”复合的苯丙氨酸，从而提高亲和力。我们对其进行了重新设计，使其经历大规模的、结合诱导的构象变化，然后用亚甲蓝氧化还原报告基因对其进行修饰，并将其连接到支持适当电化学询问的金电极上。由此产生的传感器实现了 90 nM 至 7 μM 的有用动态范围。当挑战手指刺破规模的全血样本量（稀释 1000 倍以匹配传感器的动态范围）时，该设备可在几分钟内实现准确 (±20%)、免校准的血液苯丙氨酸水平测量。