[KSCI] Korea Science Citation Index Service

http://dx.doi.org/10.5369/JSST.2011.20.4.234

Micro pH Sensor Using Patterned Hydrogel with pH Indicators

Jang, Ji-Sung (School of Electrical Engineering, Seoul National Unversity)
Kwon, Sung-Hoon (School of Electrical Engineering, Seoul National Unversity)

Publication Information

Journal of Sensor Science and Technology / v.20, no.4, 2011 , pp. 234-237 More about this Journal

Abstract

This paper presents a study into pH Indicator-Embedded hydrogel micro-particles which are encoded various shapes according to the captured indicator. We incorporate various pH indicators into a photo-curable hydrogel, PEG-DA(Poly(ethylene glycol) diacrylate). Using the latest fluidic lithography techniques, we can easily fabricate variously patterned hydrogel particles based on in-situ photopolymerization of the PEG-DA in a micro-fluidic channel. The shape of the particle is related to the pH indicator inside the particle. We demonstrate that the micro pH sensors change their colors according to the pH levels. The micro pH sensors have various characteristics that are related to the curing time, particle size, etc. By changing these conditions, we can adjust the long term stability and reaction time of the hybrid micro pH sensors.

Keywords

pH sensor; Micro-Particle; Shape Code; Hydrogel;

Citations & Related Records

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