Department of Chemistry and Biochemistry, Auburn University, Auburn, Alabama 36849, United States.
ACS Sens. 2022 Mar 25;7(3):784-789. doi: 10.1021/acssensors.1c02336. Epub 2022 Feb 18.
Although endogenous peptides and peptide-based therapeutics are both highly relevant to human health, there are few approaches for sensitive biosensing of this class of molecules with minimized workflow. In this work, we have further expanded on the generalizability of our recently developed DNA nanostructure architecture by applying it to electrochemical (EC) peptide quantification. While DNA-small molecule conjugates were used in a prior work to make sensors for small molecule and protein analytes, here DNA-peptide conjugates were incorporated into the nanostructure at the electrode surfaces, and antibody displacement permitted rapid peptide sensing. Interestingly, multivalent DNA-peptide conjugates were found to be detrimental to the assay readout, yet these effects could be minimized by solution-phase bioconjugation. The final biosensor was validated for quantifying exendin-4 (4.2 kDa)─a human glucagon-like peptide-1 receptor agonist important in diabetes therapy─for the first time using EC methods with minimal workflow. The sensor was functional in 98% human serum, and the low nanomolar assay range lies between the injected dose concentration and the therapeutic range, boding well for future applications in therapeutic drug monitoring.
虽然内源性肽和基于肽的治疗剂都与人类健康密切相关，但很少有方法可以对这类分子进行敏感的生物传感，同时尽量减少工作流程。在这项工作中，我们通过将其应用于电化学（EC）肽定量，进一步扩展了我们最近开发的 DNA 纳米结构架构的通用性。虽然在之前的工作中使用 DNA-小分子缀合物来制作小分子和蛋白质分析物的传感器，但在这里，DNA-肽缀合物被整合到电极表面的纳米结构中，并且抗体置换允许快速检测肽。有趣的是，发现多价 DNA-肽缀合物对测定结果不利，但通过溶液相生物缀合可以最小化这些影响。最后，该生物传感器通过使用最小工作流程的 EC 方法首次对人胰高血糖素样肽-1 受体激动剂 exendin-4（4.2kDa）进行了定量验证，该肽在糖尿病治疗中非常重要。该传感器在 98%的人血清中具有功能，并且纳米摩尔级的检测范围介于注射剂量浓度和治疗范围之间，这为未来在治疗药物监测中的应用提供了良好的前景。
