Department of Electrical and Bioengineering, Fairfield University, Fairfield, CT 06824, USA.
Department of Biomedical Engineering, University of Bridgeport, Bridgeport, CT 06604, USA.
Biosensors (Basel). 2020 Jun 24;10(6):72. doi: 10.3390/bios10060072.
It is known that different diseases have characteristic biomarkers that are secreted very early on, even before the symptoms have developed. Before any kind of therapeutic approach can be used, it is necessary that such biomarkers be detected at a minimum concentration in the bodily fluids. Here, we report the fabrication of an interdigitated sensing device integrated with polyvinyl alcohol (PVA) nanofibers and carbon nanotubes (CNT) for the detection of an inflammatory biomarker, C-reactive protein (CRP). The limit of detection (LOD) was achieved in a range of 100 ng mL and 1 fg mL in both phosphate buffered saline (PBS) and human serum (hs). Furthermore, a significant change in the electrochemical impedance from 45% to 70% (hs) and 38% to 60% (PBS) over the loading range of CRP was achieved. The finite element analysis indicates that a non-redox charge transduction at the solid/liquid interface on the electrode surface is responsible for the enhanced sensitivity. Furthermore, the fabricated biosensor consists of a large electro-active surface area, along with better charge transfer characteristics that enabled improved specific binding with CRP. This was determined both experimentally and from the simulated electrochemical impedance of the PVA nanofiber patterned gold electrode.
已知不同的疾病具有特征性的生物标志物，这些标志物很早就会分泌出来，甚至在症状出现之前就已经分泌出来了。在使用任何治疗方法之前，有必要在体液中以最低浓度检测到这些生物标志物。在这里，我们报告了一种带有聚 乙烯醇（PVA）纳米纤维和碳纳米管（CNT）的叉指式感测器件的制造，用于检测炎症生物标志物 C-反应蛋白（CRP）。在磷酸盐缓冲盐水（PBS）和人血清（hs）中，检测限（LOD）在 100ng/mL 和 1fg/mL 的范围内达到。此外，在 CRP 的加载范围内，电化学阻抗从 45%到 70%（hs）和 38%到 60%（PBS）有显著的变化。有限元分析表明，电极表面固/液界面上的非氧化还原电荷传递是提高灵敏度的原因。此外，所制造的生物传感器具有较大的电活性表面积和更好的电荷转移特性，这使其能够与 CRP 更好地结合。这是通过实验和模拟 PVA 纳米纤维图案化金电极的电化学阻抗来确定的。
