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Abstract Using a spatially varying light pattern with light activated semi‐conductor based magnetic micromotors, we study the difference in micromotor flux between illuminated and non‐illuminated regions in the presence and absence of an applied magnetic field. We find that the magnetic field enhances the flux of the motors which we attribute to a straightening of the micromotor trajectories which decreases the time they spend in the illuminated region. We also demonstrate spatially patterned light‐induced aggregation of the micromotors and study its time evolution at various micromotor concentrations. Although light induced aggregation has been observed previously, spatial patterning of aggregation demonstrates a further means of control which could be relevant to swarm control or self‐assembly applications. Overall, these results draw attention to the effect of trajectory shape on the flux of active colloids as well as the concentration dependence of aggregation and its time dependence within a spatially patterned region, which is not only pertinent to self‐assembly and swarm control, but also provides insight into the behavior of active matter systems with spatially varying activity levels.
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Biomembrane‐Functionalized Micromotors: Biocompatible Active Devices for Diverse Biomedical Applications
Abstract There has been considerable interest in developing synthetic micromotors with biofunctional, versatile, and adaptive capabilities for biomedical applications. In this perspective, cell membrane‐functionalized micromotors emerge as an attractive platform. This new class of micromotors demonstrates enhanced propulsion and compelling performance in complex biological environments, making them suitable for various in vivo applications, including drug delivery, detoxification, immune modulation, and phototherapy. This article reviews various proof‐of‐concept studies based on different micromotor designs and cell membrane coatings in these areas. The review focuses on the motor structure and performance relationship and highlights how cell membrane functionalization overcomes the obstacles faced by traditional synthetic micromotors while imparting them with unique capabilities. Overall, the cell membrane‐functionalized micromotors are expected to advance micromotor research and facilitate its translation towards practical uses.
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- Award ID(s):
- 1904702
- PAR ID:
- 10362385
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Advanced Materials
- Volume:
- 34
- Issue:
- 5
- ISSN:
- 0935-9648
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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