Department of Chemical Sciences and Technologies, University of Rome Tor Vergata, Via della Ricerca Scientifica 1, 00133, Roma, Italy.
Department of Chemical Sciences and Technologies, University of Rome Tor Vergata, Via della Ricerca Scientifica 1, 00133, Roma, Italy; Department of Electrical and Information Engineering, University of Cassino and Southern Lazio, 03043, Cassino, FR, Italy.
Biosens Bioelectron. 2022 Oct 1;213:114467. doi: 10.1016/j.bios.2022.114467. Epub 2022 Jun 8.
IL-6 detection is highly desirable since can monitor many diseases in humans and assess the response to treatments. Herein, two novel label-free voltammetric immunosensors for rapid and accurate interleukin-6 (IL-6) detection in human serum are presented. The immunosensors are fabricated by immobilising two different IL-6 antibodies, identified as mAb-IL-6 clone-5 and clone-7, on in-house produced screen-printed electrodes modified with inexpensive recycling biochar (Bio-SPEs). To ensure high structural fidelity and performance, an in-depth electrochemical characterization of the layer-by-layer assembly of the immunosensor was conducted by cyclic voltammetry (CV) and sensing was performed using square wave voltammetry (SWV). The two immunosensors showed good analytical performances in human serum, exhibiting a wide linear range (LR) between 26-125 and 30-138 pg/mL, a good limit of detection (LOD) of 4.8 and 5.4 pg/mL and selectivity for IL-6 over other common cytokines, including IL-1β and TNF-α. Performance comparison of IL-6 immunosensors with those of a commercial spectrophotometric ELISA kit (LOD of 20 pg/mL, RSD% of 15%) denotes a better sensitivity and reproducibility of the proposed label-free devices, associated with a reduced detection time (30 min instead of more than 3 h for ELISA test). Furthermore, the proposed immunosensors were successfully applied in blood samples (with only a dilution of 1:100 v/v in PBS and without additional treatments) with good sensitivity (LOD of 14.3 pg/mL) and reproducibility (RSD% < 11%), thus paving the way for their application as viable diagnostic and therapeutic point-of-care tools alternative to the IL-6 detection techniques routinely used (ELISA and Western Blot).
IL-6 的检测非常重要，因为它可以监测人类的许多疾病，并评估治疗反应。本文介绍了两种新型的无标记伏安免疫传感器，用于快速准确地检测人血清中的白细胞介素 6 (IL-6)。该免疫传感器通过将两种不同的 IL-6 抗体（分别命名为 mAb-IL-6 clone-5 和 clone-7）固定在自制的带有廉价回收生物炭的丝网印刷电极（Bio-SPEs）上进行制备。为了确保具有高结构保真度和性能，通过循环伏安法（CV）对免疫传感器的层层组装进行了深入的电化学表征，并通过方波伏安法（SWV）进行了传感。两种免疫传感器在人血清中均表现出良好的分析性能，具有宽线性范围（LR）分别为 26-125 和 30-138 pg/mL、低检测限（LOD）分别为 4.8 和 5.4 pg/mL，并且对 IL-6 具有选择性，对其他常见细胞因子（包括 IL-1β 和 TNF-α）具有较高的选择性。与商业分光光度 ELISA 试剂盒（LOD 为 20 pg/mL，RSD%为 15%）相比，IL-6 免疫传感器的性能比较表明，所提出的无标记器件具有更好的灵敏度和重现性，检测时间更短（30 分钟，而 ELISA 测试则超过 3 小时）。此外，该免疫传感器成功应用于血液样本（仅在 PBS 中稀释 1:100 v/v，无需额外处理），具有良好的灵敏度（LOD 为 14.3 pg/mL）和重现性（RSD%<11%），为其作为替代常规使用的 IL-6 检测技术（ELISA 和 Western Blot）的可行的诊断和治疗即时检测工具铺平了道路。
