title: Rapid 3D Patterning of Poly(acrylic acid) Ionic Hydrogel for Miniature pH Sensors.
abstract: Poly(acrylic acid) (PAA), as a highly ionic conductive hydrogel, can reversibly swell/deswell according to the surrounding pH conditions. An optical maskless -stereolithography technology is presented to rapidly 3D pattern PAA for device fabrication. A highly sensitive miniature pH sensor is demonstrated by in situ printing of periodic PAA micropads on a tapered optical microfiber.
authors.affiliation: Photonics Research Center, Department of Electrical Engineering, The Hong Kong Polytechnic University, Kowloon, Hong Kong, SAR, China.
authors.forename: Ming-Jie
authors.initials: MJ
authors.lastname: Yin
authors.affiliation: Photonics Research Center, Department of Electrical Engineering, The Hong Kong Polytechnic University, Kowloon, Hong Kong, SAR, China.|Photonics Research Center, Department of Electronic and Information Engineering, The Hong Kong Polytechnic University, Kowloon, Hong Kong, SAR, China.
authors.forename: Mian
authors.initials: M
authors.lastname: Yao
authors.affiliation: Photonics Research Center, Department of Electrical Engineering, The Hong Kong Polytechnic University, Kowloon, Hong Kong, SAR, China.
authors.forename: Shaorui
authors.initials: S
authors.lastname: Gao
authors.affiliation: Photonics Research Center, Department of Electrical Engineering, The Hong Kong Polytechnic University, Kowloon, Hong Kong, SAR, China.
authors.forename: A Ping
authors.initials: AP
authors.lastname: Zhang
authors.affiliation: Photonics Research Center, Department of Electrical Engineering, The Hong Kong Polytechnic University, Kowloon, Hong Kong, SAR, China.
authors.forename: Hwa-Yaw
authors.initials: HY
authors.lastname: Tam
authors.affiliation: Photonics Research Center, Department of Electronic and Information Engineering, The Hong Kong Polytechnic University, Kowloon, Hong Kong, SAR, China.
authors.forename: Ping-Kong A
authors.initials: PK
authors.lastname: Wai
keywords: ionic hydrogels; optical biosensors; optical stereolithography; pH sensors; photopolymerization