Parallel multiphase nanofluidics utilizing nanochannels with partial hydrophobic surface modification and application to femtoliter solvent extraction
Parallel multiphase nanofluidics utilizing nanochannels with partial hydrophobic surface modification and application to femtoliter solvent extraction
复制标题
DOI：
10.1039/c9lc00793h
复制
发表时间：
2019-11-21
期刊：
影响因子：
6.1
通讯作者：
Kitamori, Takehiko
中科院分区：
文献类型：
--
作者：
Kazoe, Yutaka;Ugajin, Takuya;Kitamori, Takehiko
在微流体领域，利用沿着微通道具有不混溶的液/液或气/液界面的平行多相流已经实现了用于分析和合成的各种化学过程的集成。最近，我们的团队开发了利用100 nm纳米通道实现超小（aL到fL规模）和高效化学操作的纳米流体。新的应用，如单分子分析和单细胞组学的预期。然而，在纳米通道中形成平行多相流仍然具有挑战性。为此，在这里，我们开发了一种新的方法，利用聚焦离子束的纳米通道的纳米级部分疏水表面改性。即使在60 nm的玻璃纳米通道中，疏水和亲水区域也可以彼此相邻地图案化。由于这种图案化基于润湿性的差异维持了纳米通道中的液/液界面，因此首次实现了40 fL纳米通道中的稳定的水/有机平行两相流。利用该流程，整合了涉及相汇合、提取和相分离的纳米级单元操作，以根据Bligh-Dyer方法证明脂质的溶剂提取，Bligh-Dyer方法是脂质组学中广泛使用的预处理过程。我们完成了在4 fL的样品体积（比单个细胞的pL体积小250倍）中的脂质和氨基酸的分离，处理时间为1 ms（比在微通道中快10000倍）。因此，这项研究提供了一个技术突破，推进了纳米流体领域，使多相化学处理在fL体积。
In the field of microfluidics, utilizing parallel multiphase flows with immiscible liquid/liquid or gas/liquid interfaces along a microchannel has achieved the integration of various chemical processes for analyses and syntheses. Recently, our group has developed nanofluidics that exploits 100 nm nanochannels to realize ultra-small (aL to fL scale) and highly efficient chemical operations. Novel applications such as single-molecule analyses and single-cell omics are anticipated. However, the formation of parallel multiphase flows in a nanochannel remains challenging. To this end, here we developed a novel method for nanoscale partial hydrophobic surface modification of a nanochannel utilizing a focused ion beam. Hydrophobic and hydrophilic areas could be patterned beside one another even in a 60 nm glass nanochannel. Because this patterning maintained the liquid/liquid interface in the nanochannel based on the difference in wettability, stable aqueous/organic parallel two-phase flow in a 40 fL nanochannel was realized for the first time. Utilizing this flow, nanoscale unit operations involving phase confluence, extraction and phase separation were integrated to demonstrate solvent extraction of a lipid according to the Bligh-Dyer method, which is a broadly used pretreatment process in lipidomics. We accomplished the separation of a lipid and an amino acid in a sample volume of 4 fL (250 times smaller than the pL volume of a single cell) with a processing time of 1 ms (10 000 times faster than that in a microchannel). This study therefore provides a technological breakthrough that advances the field of nanofluidics to allow multiphase chemical processing at fL volumes.