Department of Chemistry and Biochemistry, University of California Santa Barbara, Santa Barbara, California 93106, United States.
Center for Bioengineering, University of California Santa Barbara, Santa Barbara, California 93106, United States.
Anal Chem. 2021 Mar 2;93(8):4023-4032. doi: 10.1021/acs.analchem.0c05024. Epub 2021 Feb 17.
Current knowledge of the disposition kinetics of endogenous metabolites is founded almost entirely on poorly time-resolved experiments in which samples are removed from the body for later, benchtop analysis. Here, in contrast, we describe real-time, seconds-resolved measurements of plasma phenylalanine collected in situ in the body via electrochemical aptamer-based (EAB) sensors, a platform technology that is independent of the reactivity of its targets and thus is generalizable to many. Specifically, using indwelling EAB sensors, we have monitored plasma phenylalanine in live rats with a few micromolar precision and a 12 s temporal resolution, identifying a large-amplitude, few-seconds phase in the animals' metabolic response that had not previously been reported. Using the hundreds of individual measurements that the approach provides from each animal, we also identify inter-subject variability, including statistically significant differences associated with the feeding status. These results highlight the power of in vivo EAB measurements, an advancement that could dramatically impact our understanding of physiology and provide a valuable new tool for the monitoring and treatment of metabolic disorders.
目前对内源性代谢物处置动力学的了解几乎完全基于时间分辨率较差的实验，这些实验中样本是从体内取出后进行台式分析的。相比之下，在这里我们描述了通过电化学适体（EAB）传感器在体内实时、秒分辨率测量的血浆苯丙氨酸，这是一种独立于其靶标反应性的平台技术，因此可推广应用于许多靶标。具体来说，我们使用留置式 EAB 传感器以几微摩尔的精度和 12 秒的时间分辨率监测活体大鼠的血浆苯丙氨酸，发现了动物代谢反应中以前未报道的大振幅、几秒钟的相位。使用该方法从每个动物提供的数百个单独测量值，我们还确定了个体间的可变性，包括与进食状态相关的具有统计学意义的差异。这些结果突出了体内 EAB 测量的强大功能，这一进展可能会极大地影响我们对生理学的理解，并为代谢紊乱的监测和治疗提供一个有价值的新工具。
