氧化石墨烯集成腐蚀型81°倾斜光栅生物传感器

Biosensor Based on Cladding-etched 81° Tilted Fiber Grating Coated with Graphene Oxide

为了改善普通81°倾斜光纤光栅在生化检测中灵敏度低、检测极限不理想等问题,提出一种基于氧化石墨烯修饰腐蚀型81°倾斜光纤光栅的牛血清蛋白生物传感器,分析了该传感器的原理与传感特性.使用氢氟酸溶液腐蚀减小光栅直径,提高其对折射率的灵敏度,并用氧化石墨烯修饰光栅,然后将牛血清蛋白单克隆抗体固定于光栅表面,用于对牛血清蛋白的特异性检测.实验结果表明,氧化石墨烯集成腐蚀型81°倾斜光纤光栅生物传感器对牛血清蛋白的检测范围为0.15~15 nmol/L,检测极限为~0.165 nmol/L,其线性响应区域的灵敏度为~182 pm/(nmol·L^-1),传感器的检测范围较氧化石墨烯集成标准直径81°倾斜光纤光栅有所降低,但其灵敏度提高了5.3倍,且检测极限有较大的改善.

In order to improve the sensitivity and limit of detection of 81°tilted fiber grating,bovine serum albumin immunosensor based on graphene oxide modified cladding-etched 81°tilted fiber grating was proposed,the principle and sensing properties of the sensor were analyzed.Refractive index sensitivity of 81°tilted fiber grating was improved by etching with hydrofluoric acid.Then the etched 81°tilted fiber grating was coated with graphene oxide,and bovine serum albumin monoclonal antibody were modified on the surface of 81°tilted fiber grating for the specific detection of bovine serum albumin.Experimental results show that the detection range of the immunosensor is 0.15~15 nmol/L,limit of detection^0.165 nmol/L,and the sensitivity in its linear response region is^182 pm/(nmol·L^-1).Although the detection range decrease,the sensitivity is^5.3 times of that of the un-etched graphene oxide coated 81°tilted fiber grating,and the limit of detection is also improved.