基于石墨烯偏振吸收光学传感的心血管疾病标志物的定量检测

Quantitative Detection of Cardiovascular Disease Markers Based on Graphene Polarization Absorption Optical Sensing

利用石墨烯在全反射下对不同偏振光吸收的不同,引入锁相放大系统,发展了一种基于石墨烯偏振吸收性质的新型光学传感技术。该传感技术的灵敏度和折射率分辨率分别达到了2.14×10^(7) mV/RIU和4.67×10^(-9)。通过在石墨烯表面修饰抗体,并检测抗原抗体特异性结合时引起的折射率变化,该传感技术实现了对心血管疾病标志物超敏C反应蛋白(hs-CRP)和血清淀粉样蛋白(SAA)的高灵敏度、免标记的定量检测,检测限分别为0.020μg/mL和0.023μg/mL,均远低于两者的临床检测标准10μg/mL。基于石墨烯偏振吸收的光学传感技术具有免标记、高灵敏度以及微体积检测的优点,为心血管疾病标志物的定量检测提供了新的思路。

In this study,using the difference in the absorption of different polarized light by graphene under total internal reflection,and introducing a lock-in amplifier,a new optical sensing technology was developed based on the polarization absorption properties of graphene.The sensitivity and refractive index resolution of the sensing technology were 2.1×10^(7) mV/RIU and 4.7×10^(-9),respectively.By inoculating antibodies on the surface of graphene and detecting the change in refractive index caused by the specific binding of antigen and antibody,this technology realizes high-sensitivity,label-free quantitative detection of the cardiovascular disease markers hs-CRP and SAA.The limits of detection are 0.020μg/mL and 0.023μg/mL,respectively,far lower than the clinical detection standard of 10μg/mL.The optical sensing technology based on graphene polarization absorption has the advantages of label-free,high sensitivity and micro-volume detection,which provides a new idea for the quantitative detection of cardiovascular disease markers.