Sensing system based on highly-functional cells on environmentally controlled microchips

该项目旨在在微机械芯片上培养高功能细胞，如肥大细胞和神经元细胞，并测量它们对化学刺激的反应。我们对表面改性进行了优化。芯片结构和培养环境，以便在有限的空间内培养和维持健康细胞。(1)利用PDMS（聚二甲基硅氧烷）微流控通道中的动物细胞制备了一种基于RBL-2H3肥大细胞的过敏传感器。PDMS表面在氧等离子体下长期（超过一周）培养成亲水性。用醌类荧光染料成功地测定了肥大细胞的过敏反应；这证明了我们对过敏传感器的概念。(2)用微阵列神经元芯片筛选药物阵列反应器由1248个500 × 500 × 200立方微米大小的微室组成。用不同的多肽x-x-x-x （x: Ile, Leu, Met, Phe, Val）附着在每个室的头上培养鸡胚的原代培养神经元细胞。某些类型的肽诱导轴突生长的方式与NGF（神经元生长因子）相似。细胞外信号调节激酶也被激活。这表明使用细胞培养芯片进行药物筛选是可行的。(3)微通道中神经元细胞的培养制备了方形微通道晶格。在神经元细胞（原代培养细胞和PC19细胞）放置和培养的通道交叉处排列64个电极阵列。它们沿着通道生长轴突，并根据通道连接形成网络。在四周的时间里，通过电极检测到一些神经元信号。(4)单个细胞处理芯片通过在芯片上打小孔，将许多细胞抽吸成规则的阵列。每个细胞的电穿孔是通过一对与每个孔对齐的电极进行的。成功率为5 ~ 10%。

This project aimed to culture highly-functional cells, such as mast cells and neuron cells, on micromachined chips and to measure their response against chemical stimulus. We have optimized the surface modification. chip structures and cultural environment in order to culture and sustain healthy cells in a confined space.(1) Allergy sensor using animal cells in PDMS microfluidic channel An allergy sensor based on RBL-2H3 mast cells cultured in a PDMS (polydimethylsiloxane) microfluidic channel was developed. The PDMS surface was rendered to hydrophilic under oxygen plasma for long-term (over a week) culture. Alergic, response of mast cells using quinacrine fluorescent dye was successfully measured ; this proved our concept of the allergy sensor.(2) Drug screening with microarrayed neuron chip The arrayed reactor was composed of 1248 micro chambers of 500x500x200 cubic micrometers in size. Primary culture neuron cells from a chicken embryo were cultured with variety of peptides x-x-x-x-x (x : Ile, Leu, Met, Phe, Val) attached to a bead in each chamber. Certain types of peptides induced axon growth in the similar manner to the NGF (neuron growth factor). Extracellular signal-regulated kinase was also activated. This suggests the feasibility of using a cell culture chip for drug screening.(3) Culture of neuron cells in micro channels A square lattice of microchannels were fabricated. An array of 64 electrodes was aligned with the intersection of channels where neuron cells (primary culture cells and PC19 cells) were placed and cultured. They grew axons along the channel and formed networks according to the channel connection. Some neuron signals were detected from electrodes over four weeks.(4) Individual cell handing chip Many cells were placed in a regular array by aspiration through small holes made in a chip. Electroporation to each cell was conducted by a pair of electrodes aligned to each hole. Success rate of 5-10 % was obtained.