Research Laboratory of Real Samples Analysis, Faculty of Chemistry, Iran University of Science and Technology (IUST), Tehran, 1684613114, Iran.
Electroanalytical Chemistry Research Center, Iran University of Science and Technology (IUST), Tehran, 1684613114, Iran.
Sci Rep. 2019 Feb 4;9(1):1226. doi: 10.1038/s41598-018-37573-9.
We present a highly sensitive and selective nano-biosensor for rapid, stable and highly reproducible detection of ascorbic acid (AA) in the presence of dopamine, uric acid and other interferences by a three-layer sandwich arrangement of nitrogen-doped functionalized graphene (NFG), silver nanoparticles (AgNPs) and nanostructured polyaniline (PANI) nanocomposite. The enhanced AA electrochemical properties of the NFG/AgNPs/PANI electrode is attributed to the superior conductivity of the NFG-PANI and the excellent catalytic activity of AgNPs. The critical modification of the AgNPs-grafted NFG-PANI coated on very low-cost fluorine doped tin oxide electrode (FTOE) increased the charge transfer conductivity of the electrode (the resistance drops down from 11,000 Ω to 6 Ω). The nano-biosensor was used to accurately detect AA in vitamin C tablets with the recovery of 98%. The sensor demonstrated a low detection limit of 8 µM (S/N = 3) with a very wide linear detection range of 10-11,460 µM, good reproducibility and excellent selectivity performance for AA detection. The results demonstrate that this nanocomposite is a promising candidate for rapid and selective detection of AA in practical clinical samples.
我们提出了一种高灵敏度和选择性的纳米生物传感器，用于在存在多巴胺、尿酸和其他干扰物的情况下快速、稳定和高度重现地检测抗坏血酸 (AA)。该传感器采用氮掺杂功能化石墨烯 (NFG)、银纳米粒子 (AgNPs) 和纳米结构聚苯胺 (PANI) 纳米复合材料的三层三明治结构。NFG/AgNPs/PANI 电极对 AA 的电化学性能增强归因于 NFG-PANI 的优异导电性和 AgNPs 的卓越催化活性。AgNPs 接枝的 NFG-PANI 在非常低成本的掺氟氧化锡电极 (FTOE) 上的关键修饰增加了电极的电荷转移电导率（电阻从 11000 Ω 降低到 6 Ω）。该纳米生物传感器用于准确检测维生素 C 片剂中的 AA，回收率为 98%。该传感器具有 8 μM 的低检测限（S/N=3），线性检测范围非常宽，为 10-11,460 μM，具有良好的重现性和优异的 AA 检测选择性。结果表明，该纳米复合材料是一种很有前途的用于快速和选择性检测实际临床样本中 AA 的候选物。
