表面等离子体共振(SPR)光学传感器能实现生物医学的快速、无标记、高精度检测,是生物化学分析的重要方法。研制了基于波长调制型的Kretschmann结构表面等离子体共振(SPR)生物传感系统,研究了在体溶液传感方式下的传感性能。利用不同浓度的乙醇和乙二醇溶液进行体溶液传感测试。实验结果表明,在折射率低时共振波长对折射率变化响应的灵敏度低,但响应的线性度高;随着折射率增大,共振波长对折射率的响应变化的灵敏度提高。在1.4070~1.430 RIU折射率范围内,灵敏度高达11487 nm · RIU -1。传感器的共振波长的稳定性为0.2138 nm ,可分辨最小折射率趋近10-6 RIU。所研制的波长调制型表面等离子共振传感器操作简单、灵敏度高、检测范围大,可实现浓度极低生物标记物的有效检测,在化学、生物传感领域有重要的应用。
Surface plasmon resonance (SPR) is a rapid ,label-free ,high-precision technique of biological sensing and analysis . The investigation on the characteristics of provides theoretical basis and instructions for the applications of SPR . A Kretschmann-structure surface plasmon resonance (SPR) biosensor based on wavelength modulation was developed ,and also its sensing performances in the bulk solution was investigated .Measurements with different concentrations of bulk ethanol and eth-ylene glycol solutions show that the resonant wavelength shows a low sensitivity ,but a higher linear response to the change in refractive index (RI) ,when RI is relatively smaller .With increasing refractive index ,the sensitivity of resonance wavelength to changes in the refractive index increases .In the refractive index range of 1 .407 0-1 .430 RIU ,sensitivity reaches to 11 487 nm · RIU -1 .The sensor resonance wavelength stability is 0 .213 8 nm ,and the minimum resolution of refractive index approaches to 10-6 RIU .The advantages of the surface plasmon resonance sensor developed here results in simple operation ,high sensitivi-ty ,wide detection range ,low resolution ,makes it an important candidate in chemical and biological sensing .