Date of download: 10/14/2017 Copyright © ASME. All rights reserved. From: Size-Dependent Nanoparticle Margination and Adhesion Propensity in a Microchannel J. Nanotechnol. Eng. Med. 2013;4(3):031002-031002-7. doi:10.1115/1.4025609 Figure Legend: (a) Cross-sectional scanning electron microscopy (SEM) image of 55 × 35 μm2 channel used in experiments. (b) Fluorescence images taken at the region of interest, designated by the yellow rectangle, on the top channel wall after 93 nm polystyrene spheres were flown in the channel for 20 s (left) and 360 s (right). (C) Time dependent intensity profiles across the top channel wall in the region of interest perpendicular to the flow direction. (D) Total number of particles adhered to the top channel wall in the region of interest at each 20 s intervals based on the measured intensity for a single experiment.

Date of download: 10/14/2017 Copyright © ASME. All rights reserved. From: Size-Dependent Nanoparticle Margination and Adhesion Propensity in a Microchannel J. Nanotechnol. Eng. Med. 2013;4(3):031002-031002-7. doi:10.1115/1.4025609 Figure Legend: Number of 390 nm particles adhered to the imaged surface for a single run based on the manual counting method and the intensity quantification method, respectively

Date of download: 10/14/2017 Copyright © ASME. All rights reserved. From: Size-Dependent Nanoparticle Margination and Adhesion Propensity in a Microchannel J. Nanotechnol. Eng. Med. 2013;4(3):031002-031002-7. doi:10.1115/1.4025609 Figure Legend: (a) Representative fluorescence images of the top channel wall after 360 s of continuous particle flow in 55-μm-wide channels for each nanoparticle size tested at a shear stress of 7.5 Pa. (b) The number of adhered particles (ΔNsat) normalized by the number of particles in the margination volume as a function of time for a constant particle number concentration of n = (1.0 ± 0.2) × 109 ml−1. (c) The volume of adhered particles (ΔVsat) normalized by the volume of particles in the margination volume as a function of time for a constant particle volume concentration of ϕ = 3.1 ± 0.6 vol. %. (d) Percentage of particles adhered as a function of diameter for constant n = (1.0 ± 0.2) × 109 ml−1 (filled symbols) or constant ϕ = 3.1 ± 0.6 vol. % (unfilled symbols). The data for constant n = (1.0 ± 0.2) × 109 ml−1 can be fitted with a relation of Na/Nmar = 7 × 109 d−3 (line). (e) The volume of particles adhered to the 55 × 120 μm2 imaged section of the top wall as a function of diameter for constant n = (1.0 ± 0.2) × 109 ml−1 and constant ϕ = 3.1 ± 0.6 vol. %. For all plots, the error bars indicate the random uncertainty with a confidence interval of 95%.

Date of download: 10/14/2017 Copyright © ASME. All rights reserved. From: Size-Dependent Nanoparticle Margination and Adhesion Propensity in a Microchannel J. Nanotechnol. Eng. Med. 2013;4(3):031002-031002-7. doi:10.1115/1.4025609 Figure Legend: (a) Total particle adhesion for the top and bottom walls after 360 s of continuous flow. The bars above “T” are the data for the top wall while those above “B” are the data for the bottom wall. (b) Total particle adhesion of different sized nanoparticles to the top wall of the microchannel at different flow rates maintaining constant particle concentration of 1 × 109 particles/ml.

Date of download: 10/14/2017 Copyright © ASME. All rights reserved. From: Size-Dependent Nanoparticle Margination and Adhesion Propensity in a Microchannel J. Nanotechnol. Eng. Med. 2013;4(3):031002-031002-7. doi:10.1115/1.4025609 Figure Legend: (a) The hydrodynamic, Brownian, gravitational, van der Waals, and electrostatic forces as a function of diameter for submicron polystyrene spheres in DI water at a shear rate of 500 s−1 at a constant particle number concentration of 1 × 109 particles/ml. The electrostatic force shown is that between adjacent particles in the flow. (b) Electrostatic repulsive force between a marginating particle in the fluid and the adhered particles on the wall when the volume of the adhered particles is taken to be 3.46 × 10−4 m3 adhered per m2 channel wall area and zeta potential is taken to be −42 mV.

Date of download: 10/14/2017 Copyright © ASME. All rights reserved. From: Size-Dependent Nanoparticle Margination and Adhesion Propensity in a Microchannel J. Nanotechnol. Eng. Med. 2013;4(3):031002-031002-7. doi:10.1115/1.4025609 Figure Legend: Schematic of a particle approaching the channel wall saturated with adhered particles arranged in a square lattice. The nearest neighbor distance of the adhered particles is L. The smallest distance between the marginating particle and the channel wall is h. The distance between the marginating particle and an adhered particle is r.