Department of Energy and Resources Engineering, Lab of Heat and Mass Transport at Micro-Nano Scale, College of Engineering, Peking University, Beijing 100871, China.
Biomicrofluidics. 2010 Mar 25;4(1):14111. doi: 10.1063/1.3324869.
Cryotherapy is a prospective green method for malignant tumor treatment. At low temperature, the cell viability relates with the cooling rate, temperature threshold, freezing interface, as well as ice formation. In clinical applications, the growth of ice ball must reach a suitable size as cells could not be all killed at the ice periphery. The cell death ratio at the ice periphery is important for the control of the freezing destruction. The mechanisms of cryoinjury around the ice periphery need thorough understanding. In this paper, a primary freeze-thaw control was carried out in a cell culture microchip. A series of directional freezing processes and cell responses was tested and discussed. The temperature in the microchip was manipulated by a thermoelectric cooler. The necrotic and apoptotic cells under different cryotreatment (duration of the freezing process, freeze-thaw cycle, postculture, etc.) were stained and distinguished by propidium iodide and fluorescein isothiocyanate (FITC)-Annexin V. The location of the ice front was recorded and a cell death boundary which was different from the ice front was observed. By controlling the cooling process in a microfluidic channel, it is possible to recreate a sketch of biological effect during the process of simulated cryosurgery.
冷冻疗法是一种治疗恶性肿瘤的有前景的绿色方法。在低温下，细胞活力与冷却速率、温度阈值、冷冻界面以及冰晶形成有关。在临床应用中，冰球的生长必须达到合适的大小，因为不能在冰缘杀死所有的细胞。冰缘处的细胞死亡率对于控制冷冻破坏很重要。需要深入了解冰缘周围的冷冻损伤机制。在本文中，在细胞培养微芯片中进行了初步的冻融控制。测试并讨论了一系列定向冷冻过程和细胞反应。微芯片中的温度由热电冷却器控制。通过碘化丙啶和异硫氰酸荧光素（FITC）-膜联蛋白 V 对不同冷冻处理（冷冻过程持续时间、冻融循环、培养后等）下的坏死和凋亡细胞进行染色和区分。记录冰前沿的位置，并观察到不同于冰前沿的细胞死亡边界。通过控制微流道中的冷却过程，可以在模拟冷冻手术过程中重现生物效应的草图。
