Nanoslit membrane-integrated fluidic chip for protein detection based on size-dependent particle trapping

Abstract

This paper describes the fabrication of a nanoslit membrane-integrated fluidic chip (Nanoslit-Chip) used for trapping and concentrating micro-/nano-particles of desired size and its application in detecting biological molecules based on target-induced particle aggregation. To trap particles of a specific size, a large scale uniform sized nanoslit fluid channel array is fabricated on a silicon dioxide membrane. A small number of fluorescence labeled particles in a large volume of solution are concentrated into a monolayer of particles in a small nanoslit membrane, which enables us to effectively quantify them via fluorescence intensity. In addition, the particles of desired size (1.8 μm) are readily separated from the mixture of particles with a different size (450 nm) in Nanoslit-Chip size, and then quantified via fluorescence measurements. Finally, the Nanoslit-Chip is successfully applied to the sensitive detection of proteins by target-induced particle aggregation, trapping, and quantification. This shows its potential as a biological and clinical device for quantitative and sensitive detection of biological molecules.

Nanoslit-concentration-chip integrated microbead-based protein assay system for sensitive and quantitative detection

“…Previously, we have developed a nanoslit membrane structure for size-dependent particle trapping, 19 which enabled particle separation, concentration, and quantication. Herein, we demonstrate a new assay strategy based on the nanoslitconcentration-chip (NC-chip) integrated microbead assay system for the sensitive and quantitative detection of target biomolecules.…”

Mixed-scale channel networks including Kingfisher-beak-shaped 3D microfunnels for efficient single particle entrapment

“…The unique features of nanochannels with a characteristic size smaller than 100 nm include ion concentration polarization (ICP), 1,2 electrical double layer (EDL) overlap, 3,4 ion rectification, 5 and nanocapillarity. 6 These features enable their application in areas such as DNA manipulation, [7][8][9] seawater desalination, 10 nanofiltration, 11 nanofluidic transistors, 12,13 biosensors, 14 nanofluidic diodes, 15 protein preconcentration 16,17 and detection, 18 and nanoelectroporation (NEP). [19][20][21][22] NEP is emerging as a precise tool for a single cell study that is more efficient than bulk electroporation (BEP) or microfluidics-based electroporation (MEP) in cell transfection, because of its low cell damage and deformation, very short electroporation duration, high efficiency, and precise dose control.…”

Buried centimeter-long micro- and nanochannel arrays in porous silicon and glass

“…The DIPS process (direct imprinting of porous substrates) uses porous silicon as an imprintable material for use in plasmonics, holography, and sensing. 23,24 Micro-and nanofluidics [25][26][27] rely on the ability to fabricate small grooves and hollow channels as the basic building blocks of structures and devices, acting as connectors between valves and pumps, sensors, 28 separation columns for chromatography, 29,30 waveguides 31 or heat exchangers. 32,33 Polymers such as PDMS are widely used but have limitations when the channel diameter is reduced as they suffer from swelling which reduces the channel area or even completely closes it.…”