Micro/nanoparticle separation via curved nano-gap device with enhanced size resolution.
Micro/nanoparticles are widely found in industry and biological field to play important roles and particle size distribution is an important factor to evaluate these particles. Nano-gap device has advantages in size determination for particles in diverse size and/or shape, but it has difficulty in practical use due to severe requirement on instrumental alignment to reproduce the gap profile and non-quantitative sample injection based on capillary action. To solve these problems, curved nano-gap device (CGD) was fabricated from two flat glass plates via a simple microfabrication process to gain enhanced size resolution, and pressure-driven liquid delivery system was coupled to CGD. The gap was precisely controlled by wet etching with hydrofluoric acid on a glass plate to obtain the depth of 35.5±15.0nm on average. CGD utilized glass deflection with 18.1nm elevation/μm lateral distance that achieved practical size resolutions of 14.5nm, which was 15.7% smaller than that of conventional linear nano-gap device. Using CGD, particles from 0.5 to 10μm diameter were trapped and separated. The estimated sizes of the trapped particles matched the suggested values well. Cell sizes were also measured by CGD and the measured values matched with the values found by microscope observation. CGD acquired reproducible instrumental setup that resulted in robust analysis on size of micro/nanoparticles.
Quantitative Biology Center, RIKEN, 1-3 Yamadaoka, Suita, Osaka 565-0871, Japan. Electronic address: nobutoshi.ota@riken.jp.
Nobutoshi
N
Ota
Quantitative Biology Center, RIKEN, 1-3 Yamadaoka, Suita, Osaka 565-0871, Japan.
Yuri
Y
Owa
Quantitative Biology Center, RIKEN, 1-3 Yamadaoka, Suita, Osaka 565-0871, Japan; Japan Science and Technology Agency, PRESTO, 4-1-8 Honmachi, Kawaguchi, Saitama 332-0012, Japan.
Takayuki
T
Kawai
Quantitative Biology Center, RIKEN, 1-3 Yamadaoka, Suita, Osaka 565-0871, Japan; Graduate School of Frontier Biosciences, Osaka University, 1-3 Yamadaoka, Suita, Osaka 565-0871, Japan.
Yo
Y
Tanaka
D053595:Embryonic Stem Cells / Q000166:cytology; D005898:Glass / Q000737:chemistry; D006801:Humans; D006858:Hydrofluoric Acid / Q000737:chemistry; D019169:Jurkat Cells; D008856:Microscopy, Fluorescence; D053758:Nanoparticles / Q000737:chemistry*; D036103:Nanotechnology / Q000295:instrumentation / Q000379:methods; D010316:Particle Size; D011137:Polystyrenes / Q000737:chemistry / Q000302:isolation & purification; D011312:Pressure
D011137:Polystyrenes; D006858:Hydrofluoric Acid
Glass etching; Microchip; Microfabrication; Nanogap; Nanoparticle