基于金属橡胶和介电泳效应的微粒循环过滤实验研究

Experimental study on circulating filtration of micro particles based on metal rubber and dielectrophoretic effect

为改善金属橡胶板的过滤能力,将多孔金属橡胶板与介电泳力相结合,并利用液态金属在受限空间内的高效泵送功能,研究了金属橡胶板对5μm聚苯乙烯微球的过滤性能。实验中,将一对金属橡胶板平行嵌入至闭环微流体循环通道内,以实现介电泳力的交流电场梯度。结果表明:由于金属橡胶板内部孔径远大于聚苯乙烯微球直径,在未施加交流电信号的情况下,较难实现过滤功能;而对两个金属橡胶板适当通电,则电解液中的聚苯乙烯微球将被短距离的介电泳力收集于金属橡胶板周围,明显提高过滤效率。

In order to improve the filtration capacity of the metal rubber sheet,the porous metal rubber sheet is combined with the dielectrophoresis,and the high-efficiency pumping function of the liquid metal droplet in the confined space is utilized to research the filtration performance of the metal rubber sheet on the 5μm polystyrene microspheres.A pair of metal rubber sheets is parallelly embedded in the close-looped circulating microfluidics channel to achieve an AC field gradient for effective dielectrophoresis.The results show that it is difficult to realize the filtering function without applying an AC electric field as the aperture of the pores inside the metal rubber sheet is much larger than the diameter of latex beads.As long as the two pairs of electrodes are energized synergistically,the suspended colloids can be trapped by shortrange dielectrophoresis force near the metal rubber sheets,which can significantly improve the filtering quality.