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Updated: Dec 25, 2025
Preparation of Silicon Nanowire Field-effect Transistor for Chemical and Biosensing Applications
Published on: April 21, 2016
Facile preparation of FITC-modified silicon nanodots for ratiometric pH sensing and imaging
Yanan Zhang1, Dajun Hou2, Xueli Yu1
1Hubei Key Laboratory for Processing and Application of Catalytic Materials, College of Chemistry and Chemical Engineering, Huanggang Normal University, Huanggang 438000, China.
Abstract:
A ratiometric fluorescent pH sensor was facilely constructed by covalent modification of amino-terminated silicon nanodots (SiND) with pH-sensitive fluorescein isothiocyanate (FITC). After optimization, the SiND-FITC(40:1) material with a SiND:FITC initial mass ratio of 40:1 was selected for the sensing of hydrogen ions. It was observed that the material inherits the unique features of SiND and FITC, and there is significant improvement of SiND acid-base stability, which is a favorable factor in terms of providing fluorescence reference signal. The SiND-FITC(40:1) material displays not only high pH sensitivity, but also good stability and anti-interference ability, and the response process is highly reversible. Deploying the SiND-FITC(40:1) material, we have made available a simple, sensitive, and precise approach for pH sensing. In aqueous solutions, the I517/I466 fluorescence intensity ratio of SiND-FITC(40:1) increases linearly in the pH range of 5.40-7.76. This dual emission nanosensor was successfully applied for pH sensing and cellular fluorescence imaging.
