Department of Bioengineering, Imperial College London, London, SW7 2AZ, UK.
Department of Ophthalmology, Duke University School of Medicine, Durham, NC, 27710, USA.
Adv Healthc Mater. 2017 Aug;6(16). doi: 10.1002/adhm.201700383. Epub 2017 May 17.
Nitric oxide (NO) is a free radical signaling molecule that plays a crucial role in modulating physiological homeostasis across multiple biological systems. NO dysregulation is linked to the pathogenesis of multiple diseases; therefore, its quantification is important for understanding pathophysiological processes. The detection of NO is challenging, typically limited by its reactive nature and short half-life. Additionally, the presence of interfering analytes and accessibility to biological fluids in the native tissues make the measurement technically challenging and often unreliable. Here, a bio-inspired peptide-based NO sensor is developed, which detects NO-derived oxidants, predominately peroxynitrite-mediated nitration of tyrosine residues. It is demonstrated that these peptide-based NO sensors can detect peroxynitrite-mediated nitration in response to physiological shear stress by endothelial cells in vitro. Using the peptide-conjugated fluorescent particle immunoassay, peroxynitrite-mediated nitration activity with a detection limit of ≈100 × 10 m is detected. This study envisions that the NO detection platform can be applied to a multitude of applications including monitoring of NO activity in healthy and diseased tissues, localized detection of NO production of specific cells, and cell-based/therapeutic screening of peroxynitrite levels to monitor pronitroxidative stress in biological samples.
一氧化氮（NO）是一种自由基信号分子，在调节多个生物系统的生理稳态方面发挥着关键作用。NO 失调与多种疾病的发病机制有关；因此，其定量检测对于理解病理生理过程非常重要。NO 的检测具有挑战性，通常受到其反应性和短半衰期的限制。此外，内源性组织中存在干扰分析物和生物流体的可及性，使得测量具有技术挑战性，并且通常不可靠。在这里，开发了一种基于仿生肽的 NO 传感器，它可以检测到源自 NO 的氧化剂，主要是过氧亚硝酸盐介导的酪氨酸残基硝化。研究表明，这些基于肽的 NO 传感器可以检测到体外内皮细胞对生理剪切应力的反应而过氧亚硝酸盐介导的硝化。使用肽偶联荧光颗粒免疫测定法，可以检测到检测限约为 100×10 m 的过氧亚硝酸盐介导的硝化活性。本研究设想，NO 检测平台可以应用于多种应用，包括监测健康和患病组织中的 NO 活性、特定细胞中 NO 产生的局部检测以及基于细胞/治疗的过氧亚硝酸盐水平筛选，以监测生物样本中的促硝化应激。
