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Title: Size-Selective Sub-micrometer-Particle Confinement Utilizing Ionic Entropy-Directed Trapping in Inscribed Nanovoid Patterns
We have developed a single-step, high-throughput methodology to selectively confine submicron particles of a specific size into sequentially inscribed nanovoid patterns by utilizing electrostatic and entropic particle-void interactions in an ionic solution. The nanovoid patterns can be rendered positively charged by coating with an aluminum oxide layer, which can then localize negatively charged particles of a specific size into ordered arrays defined by the nanovoid topography. Based on the Poisson-Boltzmann model, the size-selective localization of particles in the voids is directed by the interplay between particle-nanovoid geometry, electrostatic interactions, and ionic entropy change induced by charge regulation in the electrical double layer overlapping region. The underlying principle and developed method could potentially be extended to size-selective trapping, separation, and patterning of many other objects including biological structures.  more » « less
Award ID(s):
1727918
NSF-PAR ID:
10292262
Author(s) / Creator(s):
; ; ; ; ; ;
Date Published:
Journal Name:
ACS Nano
ISSN:
1936-0851
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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