Multi-walled carbon nanotubes (MWCNT) play a synergistic role with conducting polymer in practical applications such as biological sensing. In this paper, multi-walled carbon nanotube and polypyrrole (PPy) composites were prepared on a fiber surface for the first time, and their morphology and electrical properties were characterized. Compared with PPy-coated fiber, the presence of carbon nanotubes induced the growth of large areas of PPy nanowires. In addition, fiber organic electrochemical transistors (FECTs) based on PPy and MWCNT were assembled, showing a higher on/off ratio, better stability, and greater flexibility. The lactate biosensor based on FECTs exhibits high sensitivity, with a correlation coefficient of R = 0.9889, quick response time of 0.6-0.8 s, a wide linear response range of 1 nM-1 mM, and excellent selectivity for lactate. Furthermore, the lactate concentration in human sweat was successfully detected by a FECT-based sensor. The hybrid fibers can be easily woven and placed on fabric simply by stitching. This favorable performance of the FECT-based sensor makes it suitable for noninvasive sensing of lactate. Therefore, it provides a promising platform for future use in healthcare and detection applications. Graphical abstract.

中文翻译：

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基于多壁碳纳米管和聚吡咯复合材料的纤维有机电化学晶体管，用于无创乳酸检测。

在生物传感等实际应用中，多壁碳纳米管（MWCNT）与导电聚合物起着协同作用。本文首次在纤维表面制备了多壁碳纳米管和聚吡咯（PPy）复合材料，并对其形貌和电性能进行了表征。与包覆PPy的纤维相比，碳纳米管的存在诱导了大面积PPy纳米线的生长。此外，组装了基于PPy和MWCNT的纤维有机电化学晶体管（FECT），显示出更高的开/关比，更好的稳定性和更大的柔韧性。基于FECTs的乳酸生物传感器具有很高的灵敏度，相关系数为R = 0.9889，快速响应时间为0.6-0.8 s，线性响应范围很广，为1 nM-1 mM，并且对乳酸具有出色的选择性。此外，通过基于FECT的传感器可以成功检测出人类汗液中的乳酸浓度。杂化纤维可以很容易地编织，只需缝合就可以放在织物上。基于FECT的传感器的这种良好性能使其适用于乳酸的非侵入式传感。因此，它为将来在医疗保健和检测应用中使用提供了一个有前途的平台。图形概要。