The apparent increase in hormone-induced cancers and disorders of the reproductive tract has led to a growing demand for new technologies capable of detecting endocrine disruptors. However, a long-lasting challenge unaddressed is how to achieve ultrahigh sensitive, continuous, and in situ measurement with a portable device for in-field and remote environmental monitoring. Here we demonstrate a simple-to-implement plasmonic optical fiber biosensing platform to achieve an improved light–matter interaction and advanced surface chemistry for ultrasensitive detection of endocrine disruptors. Our platform is based on a gold-coated highly tilted fiber Bragg grating that excites high-density narrow cladding mode spectral combs that overlap with the broad absorption of the surface plasmon for high accuracy interrogation, hence enabling the ultrasensitive monitoring of refractive index changes at the fiber surface. Through the use of estrogen receptors as the model, we design an estradiol–streptavidin conjugate with the assistance of molecular dynamics, converting the specific recognition of environmental estrogens (EEs) by estrogen receptor into surface-based affinity bioassay for protein. The ultrasensitive platform with conjugate-induced amplification biosensing approach enables the subsequent detection for EEs down to 1.5 × 10⁻³ ng ml⁻¹ estradiol equivalent concentration level, which is one order lower than the defined maximal E₂ level in drinking water set by the Japanese government. The capability to detect EEs down to nanogram per liter level is the lowest limit of detection for any estrogen receptor-based detection reported thus far. Its compact size, flexible shape, and remote operation capability open the way for detecting other endocrine disruptors with ultrahigh sensitivity and in various hard-to-reach spaces, thereby having the potential to revolutionize environment and health monitoring.

激素诱发的癌症和生殖道疾病的明显增加导致对能够检测内分泌干扰物的新技术的需求不断增长。然而，一个长期未解决的挑战是如何使用用于现场和远程环境监测的便携式设备实现超高灵敏度、连续和原位测量。在这里，我们展示了一个易于实施的等离子体光纤生物传感平台，以实现改进的光物质相互作用和先进的表面化学，以超灵敏地检测内分泌干扰物。我们的平台基于镀金高度倾斜的光纤布拉格光栅，可激发高密度窄包层模式光谱梳，与表面等离子体的广泛吸收重叠，以实现高精度询问，因此能够超灵敏地监测光纤表面的折射率变化。通过使用雌激素受体作为模型，我们在分子动力学的帮助下设计了一种雌二醇-链霉亲和素偶联物，将雌激素受体对环境雌激素（EEs）的特异性识别转化为基于表面的蛋白质亲和力生物测定。具有偶联物诱导扩增生物传感方法的超灵敏平台可实现低至 1.5 × 10 的 EE 后续检测^-3  ng ml ^-1雌二醇当量浓度水平，比日本政府规定的饮用水中规定的最大E _{2水平低一个数量级。}检测低至每升纳克水平的 EE 的能力是迄今为止报告的任何基于雌激素受体的检测的最低检测限。其紧凑的尺寸、灵活的形状和远程操作能力为以超高灵敏度和各种难以到达的空间检测其他内分泌干扰物开辟了道路，从而有可能彻底改变环境和健康监测。