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Dielectrophoresis is a force applied to microparticles in non-uniform electric field. The presented study discusses the fabrication of the glassy carbon interdigitated microelectrode arrays using lithography process based on lithographic patterning and subsequent pyrolysis of negative SU-8 photoresist. Resulting high resistance electrodes would have the regions of high electric field at the ends of microarray as demonstrated by simulation. The study demonstrates that combining the AC applied bias with the DC offset allows the user to separate sub-populations of microparticulates and control the propulsion of microparticles to the high field areas such as the ends of the electrode array. The direction of the movement of the particles can be switched by changing the offset. The demonstrated novel integrated DEP separation and propulsion can be applied to various fields including in-vitro diagnostics as well as to microassembly technologies.
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Non‐Uniform Electric Field Manipulation of Chromogenic Peptide Amphiphile Assemblies
Abstract This work investigates the influence of dielectrophoretic forces on the structural features and the resulting aggregates of a chromogenic model system, peptide‐diacetylene (D3GV‐DA) amphiphiles. Here, we systematically investigate how non‐uniform electric fields impact the (i) peptide‐directed supramolecular assembly stage and (ii) topochemical photopolymerization stage of polydiacetylenes (PDAs) in a quadrupole‐based dielectrophoresis (DEP) device, as well as the (iii) manipulation of D3GV‐DA aggregates in a light‐induced DEP (LiDEP) platform. The conformation‐dependent chromatic phases of peptide‐PDAs are utilized to probe the chain‐level effect of DEP exposure after the supramolecular assembly or after the topochemical photopolymerization stage. Steady‐state spectroscopic and microscopy analyses show that structural features such as the chirality and morphologies of peptidic 1‐D nanostructures are mostly conserved upon DEP exposure, but applying mild, non‐uniform fields at the self‐assembly stage is sufficient for fine‐tuning the chromatic phase ratio in peptide‐PDAs and manipulating their aggregates via LiDEP. Overall, this work provides insights into how non‐uniform electric fields offer a controllable approach to fine‐tune or preserve the molecularly preset assembly order of DEP‐responsive supramolecular or biopolymeric assemblies, as well as manipulate their aggregates using light projections, which have future implications for the precision fabrication of macromolecular systems with hierarchical structure‐dependent function.
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- PAR ID:
- 10554881
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- ChemSystemsChem
- Volume:
- 7
- Issue:
- 3
- ISSN:
- 2570-4206
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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