Browsing by Author "Horade, Mitsuhiro"

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3D pH MEASUREMENT FOR CELL CULTURE USING CT SCAN
(2017-01-01)
Higashino, Nobuya
;
Takayama, Toshio
;
Ito, Hiroaki
;
Horade, Mitsuhiro
;
Tsai, Chia-Hung Dylan
In cell culture, the pH of culture liquid is one of the most important conditions. However, culture liquid may have pH-gradient due to the activity of cells and change of the environment. In order to confirm the existence of pH-gradient, we propose a method for 3D pH measurement using the color change of phenol red. Using the principle of CT scan, we can measure pH-gradient without contacting culture liquid, and thus, decrease the possibility of contamination. In this paper, we consider the influence of light refraction by a cylindrical vessel, and show that we can measure local pH of culture liquid by light absorbance.
3D pH MEASUREMENT FOR CELL CULTURE USING CT SCAN
(2017-01-01)
Higashino, Nobuya
;
Takayama, Toshio
;
Ito, Hiroaki
;
Horade, Mitsuhiro
;
Tsai, Chia-Hung Dylan
LED-CT Scan for pH Distribution on a Cross-Section of Cell Culture Medium
(2018-01-01)
Higashino, Nobuya
;
Takayama, Toshio
;
Ito, Hiroaki
;
Horade, Mitsuhiro
;
Yamaguchi, Yasutaka
In cell culture, the pH of the culture medium is one of the most important conditions. However, the culture medium may have non-uniform pH distribution due to activities of cells and changes in the environment. Although it is possible to measure the pH distribution with an existing pH meter using distributed electrodes, the method involves direct contact with the medium and would greatly increase the risk of contamination. Here in this paper, we propose a computed tomography (CT) scan for measuring pH distribution using the color change of phenol red with a light-emitting diode (LED) light source. Using the principle of CT scan, we can measure pH distribution without contacting culture medium, and thus, decrease the risk of contamination. We have developed the device with a LED, an array of photo receivers and a rotation mechanism. The system is firstly calibrated with different shapes of wooden objects that do not pass light, we succeeded in obtaining their 3D topographies. The system was also used for measuring a culture medium with two different pH values, it was possible to obtain a pH distribution that clearly shows the boundary.
On-Chip Cell Incubator for Simultaneous Observation of Culture with and without Periodic Hydrostatic Pressure
(2019-02-01)
Horade, Mitsuhiro
;
Tsai, Chia-Hung Dylan
;
Kaneko, Makoto
;
機械工程學系
;
Department of Mechanical Engineering
This paper proposes a microfluidic device which can perform simultaneous observation on cell growth with and without applying periodic hydrostatic pressure (Yokoyama et al. Sci. Rep. 2017, 7, 427). The device is called on-chip cell incubator. It is known that culture with periodic hydrostatic pressure benefits the elasticity of a cultured cell sheet based on the results in previous studies, but how the cells respond to such a stimulus during the culture is not yet clear. In this work, we focused on cell behavior under periodic hydrostatic pressure from the moment of cell seeding. The key advantage of the proposed device is that we can compare the results with and without periodic hydrostatic pressure while all other conditions were kept the same. According to the results, we found that cell sizes under periodic hydrostatic pressure increase faster than those under atmospheric pressure, and furthermore, a frequency-dependent fluctuation of cell size was found using Fourier analysis.
Simultaneous observation of cell behavior on multiple substrates with different heights
(2017-01-01)
Taniguchi, Tsukasa
;
Horade, Mitsuhiro
;
Ito, Hiroaki
;
Takayama, Toshio
;
Tsai, Chia-Hung Dylan
We propose a microscopic system that can perform simultaneous time-lapse recordings for studying cell behavior on different substrates. The microscopic objective lens is controlled up and down so that the focal plane is matched with different heights of each surface. The captured video includes two types of images with a given time interval. Later, the focused image corresponding to each substrate is rearranged every time segment. To confirm the working principle, we show the experimental results for smooth muscle cells (SMCs) by using two different substrates.
Simultaneous observation of cell behavior on multiple substrates with different heights
(2017-01-01)
Taniguchi, Tsukasa
;
Horade, Mitsuhiro
;
Ito, Hiroaki
;
Takayama, Toshio
;
Tsai, Chia-Hung Dylan