顯微鏡細胞培養系統的渦流溫控平台

An Eddy-current-based thermal control platform for microscope cell culture system

王俊仁(Jun-Ren Wang)

指導教授 ： 婁世亮

中原大學/工學院/醫學工程研究所/碩士(2007年)

https://doi.org/10.6840/cycu200700558

摘要

生物醫學界仰賴顯微鏡活細胞培養系統之程度與日俱增，優化臻善之工作因之更為重要，尤其在該系統培養細胞之溫度、濕度與二氧化碳濃度控制為最。
本研究課題針對顯微鏡活細胞培養系統中之溫度控制系統進行改良，著重於培養皿內培養液中心位置溫度偏低之克服。所使用的方法是依據射頻電磁波可在鐵、鈷和鎳金屬上誘發渦電流並在其上產生溫升，以及射頻可使液體產生熱效應。
主要實驗設置含有一具射頻發射器和一座加熱平台。該平台仿自倒立式顯微鏡之培養皿置放機構，其特點在於該加熱平台具有加熱線圈置入及擺設不銹鋼環狀圓盤(內徑2.5 cm；外徑7 cm)的設計。實驗證實射頻對液體與不銹鋼片均產生熱效應，並顯示15 V的驅動電壓所操作的133.2 KHz之射頻電波進行液體與不銹鋼片的加溫，可獲得最均勻的溫度分佈及較快的加溫速率。藉此適用參數進行溫控測試，培養液溫度由32 ℃到37 ℃所需時間為18分鐘，在溫度分佈方面，本系統證實可將培養皿外圍與中心的溫度差異下降至1 ℃以內。
將所研發之加熱系統整合濕度與熱風控制系統作用於0.84 升之培養空間為實驗組，以市售培養箱為對照組，進行神經細胞(Neuro-2a)培養以驗證實驗組系統之實用性。經過七小時細胞培養，以MTT細胞存活率測試，結果顯示實驗組之細胞存活率為87 %。
本研究課題所研發之加熱系統具有改善培養液溫度分佈問題之能力；後續再整合二氧化碳供給系統成為完整之細胞培養裝置，應可達到更高之細胞存活率。

關鍵字

顯微鏡活細胞培養系統 ； 射頻電波 ； 加熱平台 ； 渦電流

並列摘要

Microscope incubation systems (MIS) are important for live cell studies. Cell grow in a media filled dish requires supplies and controls of temperature (37 oC), humidity (95%), and carbon dioxide concentration (5%). This course aims on improving the temperature control uniformly over the entire culture dish. The approach used to overcome this issue was based upon radio frequency (RF) technology and thermal effects it induces.
In this study a rectangle polyvinyl chloride microscope stager was fabricated where allows a stainless steel holder in a shape of donut shape be placed at the middle of the stager. The central hole of the holder was in a diameter of 2.5 cm for holding a cell culture dish and for light passing to the object lens. In addition, the holder incorporated with an antenna coil driven by a class-D power amplifier. This device produces RF and induces the Eddy current in the holder. This is the main heat source of the media around the culture dish. The control of the media temperature in the central dish was converted from the RF absorption by the media. With this setup, experimental results showed the power amplifier driven by a voltage of 15 V and inducing a radio frequency of 133.2 KHz is most suitable for this application.
By these parameters the median temperature arose from 32 to 37 oC in less than 18 minutes and the variance was less then 1 oC. The designed setup was also through a cell culture study of a Neural-2a cell line in a cubic chamber of 14 x 10 x 6 cm3 (0.84 liter). The study was evaluated by an MTT cell survival test which indicates our RF heater design can preserve 87% of the cells in contrast to those cells cultured in the standard CO2 incubator.
In conclusion, the RF heater is capable of controlling media temperature evenly over an entire cell culture dish. We have faith that this RF heater can improve the performance of MIS once the heater is integrated with the control systems of humidity and CO2.

並列關鍵字

stager ； microscope incubation systems ； Eddy current ； radio frequency

參考文獻

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