%0 Journal Article
%T 2.5-Dimensional Parylene C micropore array with a large area and a high porosity for high-throughput particle and cell separation
%J -
%D 2018
%R https://doi.org/10.1038/s41378-018-0011-8
%X Large-area micropore arrays with a high porosity are in high demand because of their promising potential in liquid biopsy with a large volume of clinical sample. However, a micropore array with a large area and a high porosity faces a serious mechanical strength challenge. The filtration membrane may undergo large deformation at a high filtration throughput, which will decrease its size separation accuracy. In this work, a keyhole-free Parylene molding process has been developed to prepare a large (>20£¿mm£¿¡Á£¿20£¿mm) filtration membrane containing a 2.5-dimensional (2.5D) micropore array with an ultra-high porosity (up to 91.37% with designed pore diameter/space of 100£¿¦Ìm/4£¿¦Ìm). The notation 2.5D indicates that the large area and the relatively small thickness (approximately 10£¿¦Ìm) of the fabricated membranes represent 2D properties, while the large thickness-to-width ratio (10£¿¦Ìm/£¿<£¿4£¿¦Ìm) of the spaces between the adjacent pores corresponds to a local 3D feature. The large area and high porosity of the micropore array achieved filtration with a throughput up to 180£¿mL/min (PBS solution) simply driven by gravity. Meanwhile, the high mechanical strength, benefiting from the 2.5D structure of the micropore array, ensured a negligible pore size variation during the high-throughput filtration, thereby enabling high size resolution separation, which was proven by single-layer and multi-layer filtrations for particle separation. Furthermore, as a preliminary demonstration, the prepared 2.5-dimensional Parylene C micropore array was implemented as an efficient filter for rare cancer cell separation from a large volume, approximately 10 cells in 10£¿mL PBS and undiluted urine, with high recovery rates of 87£¿¡À£¿13% and 56£¿¡À£¿13%, respectively
%U https://www.nature.com/articles/s41378-018-0011-8