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Abstract This paper describes the preparation, physical properties, and electric bending actuation of a new class of active materials—ionic liquid crystal elastomers (iLCEs). It is demonstrated that iLCEs can be actuated by low‐frequency AC or DC voltages of less than 1 V. The bending strains of the unoptimized first iLCEs are already comparable to the well‐developed ionic electroactive polymers. Additionally, iLCEs exhibit several novel and superior features, such as the alignment that increases the performance of actuation, the possibility of preprogrammed actuation patterns at the level of the cross‐linking process, and dual (thermal and electric) actuations in hybrid samples. Since liquid crystal elastomers are also sensitive to magnetic fields and can also be light sensitive, iLCEs have far‐reaching potentials toward multiresponsive actuations that may have so far unmatched properties in soft robotics, sensing, and biomedical applications.
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Manipulation of Single Cells Using a Ferromagnetic Nanorod Cluster Actuated by Weak AC Magnetic Fields
Abstract A unique noncontact single cell manipulation technique based on the actuation of magnetic nanorods (MNRs) or clusters (MCs) by nonuniform alternating magnetic fields (nuAMFs) is demonstrated. Compared to the actuation of MNRs/MCs by conventional magnetophoresis, the motion of MNRs/MCs actuated by nuAMFs can be tuned by additional parameters including the shape of MNRs/MCs and the frequency of the applied magnetic fields. The manipulation of a single cell by an actuated MNR/MC are divided into five stages, i.e., approaching, pushing, carrying, dragging, and releasing. The interactions between the MNR/MC and the cell in these stages are investigated in detail both experimentally and numerically. Other applications of cell manipulation, such as concentrating cells at target locations and accumulating MNRs/MCs onto a single cell, are also demonstrated. The single cell manipulation system is simple, low‐cost, and low‐power consumption, and helps advance the state‐of‐the‐art of single‐particle manipulation.
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- PAR ID:
- 10078136
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Advanced Biosystems
- Volume:
- 3
- Issue:
- 1
- ISSN:
- 2366-7478
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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