Chemical Sensing Sensitivity of Long-Period Grating Sensor Enhanced by Colloidal Gold Nanoparticles

Sensors

Jaw-Luen Tang¹ 

[1] Department of Physics, National Chung Cheng University, 168 University Road, Chia-Yi 621, Taiwan; Tel.: [phone]; Fax [phone]; E-mail:

关键词: Spectral sensitivity;    refractive index;    long-period grating;    colloidal gold nanoparticles;    localized surface plasmon resonance;   

DOI  :  10.3390/s8010171

来源: mdpi

【 摘 要 】

A simple and effective method is proposed to improve spectral sensitivity and detection limit of long period gratings for refractive index or chemical sensing, where the grating surface is modified by a monolayer of colloidal gold nanoparticles. The transmission spectra and optical properties of gold nanospheres vary with the different refractive index of the environment near the surface of gold nanospheres. The sensor response of gold colloids increases linearly with solvents of increasing refractive index. The results for the measurement of sucrose and sodium chloride solutions are reported, which show that this type of sensor can provide a limiting resolution of ∼10^-3 to ∼10^-4 for refractive indices in the range of 1.34 to 1.39 and a noticeable increase in detection limit of refractive index to external medium.

【 授权许可】

Unknown   
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