-Label-free electrochemical aptasensors for cancer biomarker detection can be a promising means for early detection of cancer due to their high sensitivity, selectivity, and stability, and low cost. In this study, a highly sensitive and selective label-free electrochemical aptasensor based on carbon microelectromechanical systems (C-MEMS) was developed for the detection of platelet-derived growth factor-BB (PDGF-BB). The active electrodes of the aptasensors were synthesized via carbonization of SU-8 derived electrodes at high temperatures in an oxygen-free furnace. An oxygen-plasma oxidation treatment was used to functionalize the C-MEMS electrodes, which provided efficient covalent immobilization of amino terminated affinity aptamers. The turn-off and turn-on detection strategies–based on capacitance and resistance measurement, respectively—were employed. The capacitance detection strategies exhibited a wide linear response range of 0.01–50 nM, with a high sensitivity of 3.33 mF cm-2 Logc-1 (unit of c, nM) and a low limit of detection of 7 pM (S/N = 3). The resistance detection strategies exhibited an even wider linear response range of 0.005–50 nM, and a lower limit of detection of 1.9 pM (S/N = 3), with a high sensitivity of 1.65 × 103 Ω Logc^-1 (unit of c, nM). Both detection strategies provided high selectivity for PDGF-BB and high stability of 90.34% after 10 days. This research demonstrates that the developed label-free electrochemical C-MEMS based PDGF-BB aptasensor is highly sensitive, selective, and robust. This aptasensor is a promising prospect for the highly demanding task of early detection of cancer biomarkers.

-用于癌症生物标志物检测的无标签电化学适体传感器，由于其高灵敏度，选择性，稳定性和低成本，可以成为癌症早期检测的有前途的手段。在这项研究中，开发了一种基于碳微机电系统（C-MEMS）的高灵敏度和选择性的无标记电化学适体传感器，用于检测血小板衍生的生长因子-BB（PDGF-BB）。适体传感器的活性电极是通过SU-8衍生的电极在无氧炉中在高温下碳化而合成的。氧等离子体氧化处理用于功能化C-MEMS电极，可有效地共价固定氨基末端亲和适体。关断和导通检测策略–基于电容和电阻测量，分别被雇用。电容检测策略表现出0.01–50 nM的宽线性响应范围，具有3.33 mF cm-2 Logc-1（c，nM的单位）的高灵敏度和7 pM的低检测限（S / N = 3）。电阻检测策略的线性响应范围更广，为0.005–50 nM，检测下限为1.9 pM（S / N = 3），灵敏度为1.65×103ΩLogc^-1（c的单位，nM）。两种检测策略在10天后对PDGF-BB的选择性都很高，稳定性高达90.34％。这项研究表明，基于PDGF-BB的无标记电化学C-MEMS电化学传感器具有很高的灵敏度，选择性和鲁棒性。该适体传感器对于癌症生物标志物的早期检测的高要求任务是有希望的前景。