In this study, a surface plasmon resonance sensor for detecting haemoglobin concentration based on a D-type optical fibre with a graphene-gold surface architecture is proposed. The graphene-gold surface architecture included a 50 nm thick gold film and monolayer graphene film, which were decorated on a 10 mm long D-type sensing region. The proposed sensor worked in wavelength interrogation mode, with the light wavelength ranging from 400 to 1100 nm. The authors realised the D-type optical fibre surface polishing process, the gold film vacuum coating process, and the chemical-vapour-deposited graphene's wet transfer process. Furthermore, the fabricated sensors were used to detect the refractive index (RI) of haemoglobin samples, which varied from 1.331 to 1.346. Experiment results show that the fitted RI sensitivity of the sensor decorated with gold and graphene reaches 1874.41 nm/RIU, 4.995% higher than that of the sensor decorated only with gold. The concentration sensitivity of the sensor coated with gold and graphene film is 4.96 nm/(g/dL), and the proposed sensor can provide a resolution of 20.2 mg/dL for haemoglobin concentration detection.

中文翻译：

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基于石墨烯-金表面结构的D型光纤的表面等离子体共振血红蛋白浓度传感器

在这项研究中，提出了一种基于具有石墨烯-金表面结构的D型光纤的用于检测血红蛋白浓度的表面等离子体共振传感器。石墨烯-金表面结构包括50 nm厚的金膜和单层石墨烯膜，它们装饰在10 mm长的D型传感区域上。所提出的传感器以波长询问模式工作，光波长范围为 400 至 1100 nm。作者实现了D型光纤表面抛光工艺、金膜真空镀膜工艺、化学气相沉积石墨烯湿法转移工艺。此外，所制造的传感器用于检测血红蛋白样本的折射率（RI），其范围从 1.331 到 1.346。实验结果表明，金和石墨烯修饰的传感器的拟合RI灵敏度达到1874.41 nm/RIU，比仅金修饰的传感器提高了4.995%。涂有金和石墨烯薄膜的传感器的浓度灵敏度为4.96 nm/(g/dL)，所提出的传感器可以为血红蛋白浓度检测提供20.2 mg/dL的分辨率。