title: Monitoring change in refractive index of cytosol of animal cells on affinity surface under osmotic stimulus for label-free measurement of viability.
abstract: We demonstrated that a metal-clad waveguide (MCW)-based biosensor can be applied to label-free measurements of viability of adherent animal cells with osmotic stimulation in real time. After Chinese hamster ovary (CHO) and human embryonic kidney cell 293 (HEK293) cells were attached to a Concanavalin A (Con A)-modified sensor surface, the magnitudes of cell responses to non-isotonic stimulation were compared between live and dead cells. The live cells exhibited a change in the refractive index (RI) of the cytosol caused by a redistribution of water through the cell membrane, which was induced by the osmotic stimulus, but the dead cells did not. Moreover, the normalized change in the RI measured via the MCW sensor was linearly proportional to the viability of attached cells and the resolution in monitoring cell viability was about 0.079%. Therefore, the viability of attached animal cells can be measured without labels by observing the relative differences in the RI of cytosol in isotonic and non-isotonic buffers.
authors.affiliation: Nanobiotechnology Major, Korea University of Science and Technology, 52 Eoeun-Dong, Yuseong-Gu, Daejeon 305-333, Republic of Korea; Korea Research Institute of Bioscience and Biotechnology, 52 Eoeun-Dong, Yuseong-Gu, Daejeon 305-333, Republic of Korea.
authors.forename: Jina
authors.initials: J
authors.lastname: Park
authors.affiliation: Department of Bio & Nano Chemistry, Kookmin University, Seoul 136-702, Republic of Korea.
authors.forename: Sung Il
authors.initials: SI
authors.lastname: Jin
authors.affiliation: Department of Bio & Nano Chemistry, Kookmin University, Seoul 136-702, Republic of Korea.
authors.forename: Hyung Min
authors.initials: HM
authors.lastname: Kim
authors.affiliation: Department of Nano Manufacturing Technology, Nano Convergence Mechanical Systems Research Division, Korea Institute of Machinery and Materials, Daejeon 305-343, Republic of Korea.
authors.forename: Junhyoung
authors.initials: J
authors.lastname: Ahn
authors.affiliation: Biotechnology Process Engineering Center, Korea Research Institute of Bioscience and Biotechnology, 52 Eoeun-Dong, Yuseong-Gu, Daejeon 305-333, Republic of Korea.
authors.forename: Yeon-Gu
authors.initials: YG
authors.lastname: Kim
authors.affiliation: Biotechnology Process Engineering Center, Korea Research Institute of Bioscience and Biotechnology, 52 Eoeun-Dong, Yuseong-Gu, Daejeon 305-333, Republic of Korea.
authors.forename: Eun Gyo
authors.initials: EG
authors.lastname: Lee
authors.affiliation: Department of Chemistry, Gwangju Institute of Science and Technology (GIST), Gwangju 500-712, Republic of Korea.
authors.forename: Min-Gon
authors.initials: MG
authors.lastname: Kim
authors.affiliation: Nanobiotechnology Major, Korea University of Science and Technology, 52 Eoeun-Dong, Yuseong-Gu, Daejeon 305-333, Republic of Korea; Korea Research Institute of Bioscience and Biotechnology, 52 Eoeun-Dong, Yuseong-Gu, Daejeon 305-333, Republic of Korea. Electronic address: ybshin@kribb.re.kr.
authors.forename: Yong-Beom
authors.initials: YB
authors.lastname: Shin
mesh_terms: D000818:Animals; D016466:CHO Cells; D002470:Cell Survival / Q000502:physiology*; D003412:Cricetulus; D004867:Equipment Design; D019544:Equipment Failure Analysis; D057809:HEK293 Cells; D006801:Humans; D009997:Osmotic Pressure / Q000502:physiology*; D012031:Refractometry / Q000295:instrumentation*; D020349:Surface Plasmon Resonance / Q000295:instrumentation*
keywords: Biosensor; Cell viability; Label-free measurement; Metal clad waveguide; Refractometry