Abstract
Spatiotemporal particle patterning in evaporating droplets lacks a common design framework. Here, we demonstrate autonomous control of particle distribution in evaporating droplets through the imposition of a salt-induced self-generated electric field as a generalized patterning strategy. Through modeling, a new dimensionless number, termed "capillary-phoresis" (CP) number, arises, which determines the relative contributions of electrokinetic and convective transport to pattern formation, enabling one to accurately predict the mode of particle assembly by controlling the spontaneous electric field and surface potentials. Modulation of the CP number allows the particles to be focused in a specific region in space or distributed evenly. Moreover, starting with a mixture of two different particle types, their relative placement in the ensuing pattern can be controlled, allowing coassemblies of multiple, distinct particle populations. By this approach, hypermethylated DNA, prevalent in cancerous cells, can be qualitatively distinguished from normal DNA of comparable molecular weights. In other examples, we show uniform dispersion of several particle types (polymeric colloids, multiwalled carbon nanotubes, and molecular dyes) on different substrates (metallic Cu, metal oxide, and flexible polymer), as dictated by the CP number. Depending on the particle, the highly uniform distribution leads to surfaces with a lower sheet resistance, as well as superior dye-printed displays.
| Original language | English (US) |
|---|---|
| Pages (from-to) | 43352-43362 |
| Number of pages | 11 |
| Journal | ACS Applied Materials and Interfaces |
| Volume | 9 |
| Issue number | 49 |
| DOIs | |
| State | Published - Dec 13 2017 |
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All Science Journal Classification (ASJC) codes
- Materials Science(all)
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Modulation of Spatiotemporal Particle Patterning in Evaporating Droplets : Applications to Diagnostics and Materials Science. / Guha, Rajarshi; Mohajerani, Farzad; Mukhopadhyay, Ahana; Collins, Matthew D.; Sen, Ayusman; Velegol, Darrell.
In: ACS Applied Materials and Interfaces, Vol. 9, No. 49, 13.12.2017, p. 43352-43362.Research output: Contribution to journal › Article
TY - JOUR
T1 - Modulation of Spatiotemporal Particle Patterning in Evaporating Droplets
T2 - Applications to Diagnostics and Materials Science
AU - Guha, Rajarshi
AU - Mohajerani, Farzad
AU - Mukhopadhyay, Ahana
AU - Collins, Matthew D.
AU - Sen, Ayusman
AU - Velegol, Darrell
PY - 2017/12/13
Y1 - 2017/12/13
N2 - Spatiotemporal particle patterning in evaporating droplets lacks a common design framework. Here, we demonstrate autonomous control of particle distribution in evaporating droplets through the imposition of a salt-induced self-generated electric field as a generalized patterning strategy. Through modeling, a new dimensionless number, termed "capillary-phoresis" (CP) number, arises, which determines the relative contributions of electrokinetic and convective transport to pattern formation, enabling one to accurately predict the mode of particle assembly by controlling the spontaneous electric field and surface potentials. Modulation of the CP number allows the particles to be focused in a specific region in space or distributed evenly. Moreover, starting with a mixture of two different particle types, their relative placement in the ensuing pattern can be controlled, allowing coassemblies of multiple, distinct particle populations. By this approach, hypermethylated DNA, prevalent in cancerous cells, can be qualitatively distinguished from normal DNA of comparable molecular weights. In other examples, we show uniform dispersion of several particle types (polymeric colloids, multiwalled carbon nanotubes, and molecular dyes) on different substrates (metallic Cu, metal oxide, and flexible polymer), as dictated by the CP number. Depending on the particle, the highly uniform distribution leads to surfaces with a lower sheet resistance, as well as superior dye-printed displays.
AB - Spatiotemporal particle patterning in evaporating droplets lacks a common design framework. Here, we demonstrate autonomous control of particle distribution in evaporating droplets through the imposition of a salt-induced self-generated electric field as a generalized patterning strategy. Through modeling, a new dimensionless number, termed "capillary-phoresis" (CP) number, arises, which determines the relative contributions of electrokinetic and convective transport to pattern formation, enabling one to accurately predict the mode of particle assembly by controlling the spontaneous electric field and surface potentials. Modulation of the CP number allows the particles to be focused in a specific region in space or distributed evenly. Moreover, starting with a mixture of two different particle types, their relative placement in the ensuing pattern can be controlled, allowing coassemblies of multiple, distinct particle populations. By this approach, hypermethylated DNA, prevalent in cancerous cells, can be qualitatively distinguished from normal DNA of comparable molecular weights. In other examples, we show uniform dispersion of several particle types (polymeric colloids, multiwalled carbon nanotubes, and molecular dyes) on different substrates (metallic Cu, metal oxide, and flexible polymer), as dictated by the CP number. Depending on the particle, the highly uniform distribution leads to surfaces with a lower sheet resistance, as well as superior dye-printed displays.
UR - http://www.scopus.com/inward/record.url?scp=85038216169&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=85038216169&partnerID=8YFLogxK
U2 - 10.1021/acsami.7b13675
DO - 10.1021/acsami.7b13675
M3 - Article
C2 - 29143530
AN - SCOPUS:85038216169
VL - 9
SP - 43352
EP - 43362
JO - ACS applied materials & interfaces
JF - ACS applied materials & interfaces
SN - 1944-8244
IS - 49
ER -