The sensitivity of fiber optic biosensors to detect trace biochemical molecules is highly challenging. Two-dimensional (2D) MXene is recently found to have strong sensitivity enhancement on biosensing, gas sensing, and humidity sensing because of its characteristics of metallic conductivity, hydrophilic surface, large specific surface, and wide band optical absorption. Here, for the first time, the experimental evidence supports the mechanism that the characteristics of 2D MXene Ti₃C₂T_x can enhance sensitivities of fiber optic biosensors and two kinds of fiber optic biosensors are demonstrated to compare the sensitivity enhancement between those with and without MXene decoration. Refractive index (RI) detection can be used to quantitatively reflect the detection ability of biosensors. In this paper, we use RI detection to quantify the performance improvement of our sensors. A high-performance fiber optic surface plasmon resonance sensor with a ∼30% sensitivity boost is demonstrated, and a fiber optic RI sensor exhibits an outstanding sensitivity enhancement of more than 8 times, which can be applied to the detection of most trace biochemical molecules. Additionally, the former can also tune its operation window to adapt to different detection conditions, while the latter can work in a wide spectrum with the same high quality performance. Our findings may advance the future development of MXene-based optical sensing technology.

中文翻译：

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基于Ti ₃ C ₂ T _x MXene纤维的折射率传感器

光纤生物传感器检测痕量生化分子的灵敏度非常具有挑战性。二维（2D）MXene由于具有金属导电性，亲水性表面，较大的比表面积和宽带光吸收特性，因此在生物传感，气体传感和湿度传感方面具有很强的灵敏度增强。在这里，实验证据首次支持了2D MXene Ti ₃ C ₂ T _x的特性的机理。可以提高光纤生物传感器的灵敏度，并演示了两种光纤生物传感器来比较具有和不具有MXene装饰的传感器之间的灵敏度增强。折射率（RI）检测可用于定量反映生物传感器的检测能力。在本文中，我们使用RI检测来量化传感器性能的提高。展示了一种高性能光纤表面等离子体激元共振传感器，其灵敏度提高了约30％，而光纤RI传感器的灵敏度则提高了8倍以上，可用于检测大多数痕量生化分子。此外，前者还可以调整其操作窗口以适应不同的检测条件，后者可以以相同的高质量性能在广泛的范围内工作。我们的发现可能会推动基于MXene的光学传感技术的未来发展。