基于薄膜电极的细胞电融合芯片

Thin Film Electrode Based Cell Electrofusion Chip

构建了一种薄膜电极阵列结构的细胞电融合芯片,通过多聚物微通道底/顶层凸齿状的微电极,以及多聚物微通道侧壁上溅射形成的一层离散式金属薄膜电极,共同形成离散式"三明治"微电极结构.该微电极结构可在微通道内部形成与传统凸齿状电极相似的非均匀分布的梯度电场,通过介电电泳效应进行细胞控制及排队.利用多聚物在芯片上填充了传统凸齿状电极的凹陷区,克服了细胞在凹陷区无法有效排队与融合的缺点.在芯片上利用K562细胞开展了基于介电电泳效应的细胞排队实验及基于可逆性电穿孔效应的电融合实验,结果表明该芯片能够较好地实现细胞排队及融合,融合所需控制电压低至10 V左右.细胞排队率达99%以上,几乎无细胞在绝缘物填充区(传统凸齿电极芯片的凹陷区)滞留,细胞两两排队高于60%,细胞融合效率约为40%,比传统的细胞电融合方法和凸齿电极芯片有较大提高.

A microfluidic chip based on thin film microelectrode structure was developed for high efficiency cell electrofusion. The top/bottom thin film microelectrode array and the discrete thin film microelectrodes sputtered on the sidewalls of the polymer（ Durimide 7510） microchannel constructed the discrete ＂sandwich＂ microelectrode structure. As the traditional protruding microelectrodes, this structure could generate nonuniform electric field for dieleetrophoresis-based cell alignment/pairing between the mierochannel. The cavity between two adjacent microeledctrodes was also filled using the Durimide 7510. It could overcome the shortcoming in the traditional protruding cell-electrofusion chip where many ceils could not be aligned and fused in the unfilled cavity. Experimental investigation of cell alignment based on dielectrophoresis and cell electrofusion based on reversible electroporation were conducted using K562 cells and good results were achieved. Low voltage pulses （ca. 10 V） series could produce a strong enough electric field for reversible electroporation. Most cells（ca. 99% ） were trapped on the surface of the thin film microelectrodes and almost no cells were docked between two adjacent electrodes on the same sidewall. More than 60% cells were aligned as cell-cell twins and about 40% cells were fused. Thus, compared with traditional cell electrofusion method and protruding microelectrode structures, higher alignment and fusion efficiency were achieved.