基于单螺旋微流控芯片的细菌气溶胶的高效富集

Highly Efficient Enrichment of Bacteria Aerosol Based on a Single Spiral Microfluidic Chip

设计了一种单螺旋通道的聚二甲基硅氧烷（Poly（dimethylsiloxane）,PDMS）微流控芯片,用于副溶血性弧菌气溶胶的快速有效富集。该芯片的特征在于其通道呈螺旋分布,且通道内部含有均匀分布的鱼骨形结构。结果表明,在不同富集时间段内,采用该芯片方法捕获的细菌总数均远高于传统落板法。对于传统落板法无法有效捕获的低浓度样本（10~4CFU/mL）的缺陷,该方法的优势在于：芯片内部的螺旋通道可增大对气溶胶中微生物的离心力;鱼骨形结构的设计增加了待测样品与芯片内壁间的接触几率。此外,以无鱼骨形的螺旋芯片作为对照,验证了鱼骨形结构对于高效富集的意义。此芯片设计巧妙、易于制备、高效便携、富集效果较好,在气溶胶污染严重的水产加工等场所具有较大的应用前景。

Highly efficient enrichment is the key for rapid analysis and detection of microbiological aerosol. Herein,a poly（ dimethylsiloxane）（ PDMS） microfluidic chip which has a single spiral channel was developed,and the chip was used for Vibrio parahaemolyticus enrichment. The characteristic of this chip is that it has a single spiral channel which contains a herringbone structure with uniform distribution. During different enrichment times,the number of captured bacteria by microfluidic chip is far bigger than that by the traditional sediment method. Moreover,the chip shows more enrichment advantages when capturing microbiological aerosol in low concentration. This excellent enrichment ability,on one hand,benefits from the unique spiral channel design which can put greater centrifugal force to the microbiological aerosol. On the other hand,the herringbone structures design endows the chip larger surface specific area increasing the contact probability between microbiological aerosol and chip. In addition, a similar spiral microfluidic chip without herringbone structures was also designed. The results validated the contribution of herringbone structures to the enrichment efficiency.With the advantages of delicate design and fabrication,portability and high enrichment capacity,this microfluidic chip shows a great application potential in field like aquatic products processing industry.