Multi-fluorescent micro-sensor for accurate measurement of pH and temperature variations in micro-environments

SENSORS AND ACTUATORS B-CHEMICAL

卷:203

Article

Liu, Hengjun¹  Maruyama, Hisataka¹  Masuda, Taisuke¹  Honda, Ayae²  Arai, Fumihito¹ 

[1] Nagoya Univ, Dept Micronano Syst Engn, Nagoya, Aichi 4648603, Japan

[2] Hosei Univ, Dept Frontier Biosci, Tokyo 1920982, Japan

关键词: Fluorescein isothiocyanate (FITC);    Rhodamine B;    A mino-polystyrene microbeads (Ps);    pH sensitivity;    Temperature compensation;   

DOI  :  10.1016/j.snb.2014.06.079

来源: Elsevier

【 摘 要 】

In this study, a novel multi-fluorescent micro-sensor that can respond to both pH and temperature was designed and synthesized. It is based on amino-polystyrene microbeads, and two different fluorescent indicators (Rhodamine B and Fluorescein isothiocyanate) were used simultaneously to synthesize the fluorescent micro-sensor. Rhodamine B was embedded inside the amino-polystyrene microbeads, whereas Fluorescein isothiocyanate (FITC) was used to modify the surface of the beads. Because of the different fluorescence wavelengths and measurement positions of FITC and Rhodamine B, interference from eachfluorescent indicator should be avoided. The fluorescence responses of FITC and Rhodamine B to pH and temperature, respectively, were detected. Rhodamine B demonstrates an excellent linear relationship between relative fluorescence intensity and temperature, while the relative fluorescence intensity was found to be independent of the pH. The calibrated sensitivity of Rhodamine B is -3.4%/degrees C, with a temperature accuracy of 0.1 degrees C. Therefore, changes in the temperature information can be calibrated based on the relative fluorescence intensity changes in Rhodamine B. On the other hand, FITC is sensitive to both pH and temperature. We propose a temperature compensation method for pH calibration. After temperature compensation, the pH accuracy calibrated based on the pH sensitivity of FITC improves from 1.5 to 0.2. (C) 2014 Elsevier B. V. All rights reserved.

【 授权许可】

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