We have developed a sensing platform using a long-period fiber grating (LPFG) integrated black phosphorus (BP) thin film from the numerical simulation analysis and experimental process verification. Due to the high optical absorption of BP, the attenuated depth of the cladding mode in the BP coated LPFG (named BP-LPFG) sensor can be varied by the change of external environment. Benefited from the BP film, the sensing system shows a superior enhancement in the refractive index (RI) detection compared to the use of bare LPFG. The sensitivity can reach 122.1 dB/RIU, 139.5 dB/RIU, and 931.9 dB/RIU in the RI regions of 1.33–1.38, 1.39–1.44, and near 1.455, respectively. Moreover, this sensing system has been applied to implement the highly sensitive and label-free detection for the bovine hemoglobin (BHb) molecules, with a sensitivity of 5.6 dB/(mg/mL) and a detection limit of 0.05 mg/mL achieved. The detection limit is 2600 times lower than the hemoglobin threshold for the confirmation of men’s anemia illness, defined by the World Health Organization (WHO). This newly sensing platform is promising in the early clinical diagnose for anemia illness.

通过数值模拟分析和实验过程验证，我们开发了一种使用长周期光纤光栅 (LPFG) 集成黑磷 (BP) 薄膜的传感平台。由于 BP 的高光吸收性，BP 涂层 LPFG（称为 BP-LPFG）传感器中包层模式的衰减深度可以随外部环境的变化而变化。受益于 BP 薄膜，与使用裸 LPFG 相比，传感系统在折射率 (RI) 检测方面表现出卓越的增强。在1.33-1.38、1.39-1.44和1.455附近的RI区域，灵敏度分别达到122.1 dB/RIU、139.5 dB/RIU和931.9 dB/RIU。此外，该传感系统已应用于实现牛血红蛋白（BHb）分子的高灵敏度和无标记检测，灵敏度为5。6 dB/(mg/mL) 和检测限为 0.05 mg/mL。检测限比世界卫生组织 (WHO) 定义的用于确认男性贫血疾病的血红蛋白阈值低 2600 倍。这种新的传感平台在贫血疾病的早期临床诊断中很有前景。