Femtoliter high-performance liquid chromatography using extended-nano channels

Abstract

A high-performance liquid chromatography system with 35 fL sample volume was developed using extended-nano (10-1000 nm) fluidic channels. For many years, miniaturization and enhancement of separation performance have been important issues in separation science. Recently, we have reported an ultimate miniaturization of chromatography using extended-nano channels with extremely high separation efficiency of 7 × 10 plates per m. However, the real theoretical plate number was limited to 10 due to the short nanochannel length. In this paper, the theoretical plate number was dramatically increased by developing a new high-pressure system with a very long nanochannel. A separation experiment of two fluorescent dyes demonstrated that the theoretical plate number could be improved to 1.4 × 10, which is much higher than that with conventional HPLC. The theoretical plate number is also comparable to those of capillary monolithic columns. The extremely small sample volume of extended-nano chromatography could support innovative analytical techniques capable of analyzing a single living cell in the near future.

Accelerated protein digestion and separation with picoliter volume utilizing nanofluidics

“…According to previous studies of nanofluidic liquid chromatography, as the channel length increases, the theoretical plate number becomes higher. 40 To achieve a high theoretical plate number, the separation channel was designed to be w: 5 μm, d: 1 μm, and L: 30 mm. The surface of the separation channel was made hydrophobic following modification with octadecylsilane (ODS).…”

Nano liquid chromatography columns

“…Advantages of extended-nanoLC are the use of extremely small sample volumes, the speed and the high separation efficiencies (plate numbers of up to 1.4 x 10 4 ) 119 . In their review paper from 2017 118 , fundamentals of the extended-nano chromatography technique are summarized, as is the instrumentations used to realize attoliter sample injections and sensitive detection methods.…”

Metal-Free Fabrication of Fused Silica Extended Nanofluidic Channel to Remove Artifacts in Chemical Analysis

“…For example, the biotin–streptavidin reaction [ 21 , 22 ], hybridization of microRNA [ 23 ], enzymatic reactions [ 24 ], and electrochemical reactions [ 25 , 26 ] have been performed at solid/liquid interfaces in nanochannels. In our group, a picoliter enzymatic reactor [ 27 ] using an enzyme-immobilized nanochannel, and femtoliter chromatography devices [ 28 , 29 ] using silica surfaces or C 18 -modified surfaces have been developed, and their superior performance over conventional bulk methods has been verified. A femtoliter enzyme-linked immunosorbent assay (ELISA) [ 30 ] using antibody-immobilized nanochannels enabled protein quantification at the single–molecule level.…”