title: Nonradiation Cellular Thermometry Based on Interfacial Thermally Induced Phase Transformation in Polymer Coating of Optical Microfiber.
abstract: A nonradiation approach based on thermoresponsive polymer coated silica microfibers has been developed. A highly thermoresponsive and biocompatible poly(N-isopropylacrylamide) (pNIPAM) was surface functionlized to conjugate to the tapered silica microfiber with waist diameter of 7.5 μm. The interfacial phase transtition of coating triggered by the lower critical solution temperature (LCST) causes a drastic molecular morphological change in the body temperature range of 35-42 °C. This surface morphological change strongly modulates optical path difference between the higher order and the fundamental mode propagating in the microfiber because of the evanescent-field interaction and, therefore, shifts the intermodal interference fringe. Owing to the nonradiation-based nature, the thermoresponsive polymer coated microfiber enables an improved thermal sensitivity of 18.74 nm/°C and, hence, a high-temperature resolution of millidegree. Furthermore, the micrometer-sized footprint enables its easy implantation in human organs for cellular thermometry and for the potential of in vivo applications.
authors.affiliation: Guangdong Provincial Key Laboratory of Optical Fiber Sensing and Communications, Institute of Photonics Technology, Jinan University , Guangzhou 510632, China.
authors.forename: Yunyun
authors.identifier: http://orcid.org/0000-0001-7528-1001
authors.initials: Y
authors.lastname: Huang
authors.affiliation: Guangdong Provincial Key Laboratory of Optical Fiber Sensing and Communications, Institute of Photonics Technology, Jinan University , Guangzhou 510632, China.
authors.forename: Tuan
authors.initials: T
authors.lastname: Guo
authors.affiliation: Guangdong Provincial Key Laboratory of Optical Fiber Sensing and Communications, Institute of Photonics Technology, Jinan University , Guangzhou 510632, China.
authors.forename: Zhuang
authors.initials: Z
authors.lastname: Tian
authors.affiliation: Guangdong Provincial Key Laboratory of Optical Fiber Sensing and Communications, Institute of Photonics Technology, Jinan University , Guangzhou 510632, China.
authors.forename: Bo
authors.initials: B
authors.lastname: Yu
authors.affiliation: Guangdong Provincial Key Laboratory of Optical Fiber Sensing and Communications, Institute of Photonics Technology, Jinan University , Guangzhou 510632, China.
authors.forename: Mingfei
authors.initials: M
authors.lastname: Ding
authors.affiliation: Guangdong Provincial Key Laboratory of Optical Fiber Sensing and Communications, Institute of Photonics Technology, Jinan University , Guangzhou 510632, China.
authors.forename: Xiangping
authors.initials: X
authors.lastname: Li
authors.affiliation: Guangdong Provincial Key Laboratory of Optical Fiber Sensing and Communications, Institute of Photonics Technology, Jinan University , Guangzhou 510632, China.
authors.forename: Bai-Ou
authors.initials: BO
authors.lastname: Guan
keywords: cellular thermometry; coating; interface; sensor; silica microfiber; thermoresponsive polymer