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Abstract Precise manipulation of nanomaterials has shown great potential in facilitating the fabrication of functional hydrogel nanocomposites in applications such as soft robotics, biomedicine, structural health monitoring, and wearable sensing. Surface acoustic wave (SAW)-based acoustofluidics offers a contactless approach for nanoparticle manipulation. Meanwhile, digital light processing (DLP) has been extensively utilized in the hydrogel printing process due to its high-resolution fabrication capabilities. This study presents an innovative SAW acoustofluidics-assisted DLP system, enabling the patterning of nanoparticles embedded in matrix materials while facilitating programmed light exposure for the controllable photopolymerization of customized hydrogel nanocomposites. Instead of utilizing the acoustic potential field generated by SAWs, we leverage the accompanying electric field due to the piezoelectric effect of the lithium niobate (LiNbO3) substrate to generate electric field, enabling the electric field-driven patterning of multi-walled carbon nanotubes (MWCNTs) Laser Doppler vibrometry confirms the SAW-generated acoustic intensity fields. The analytical simulation together with the scanned data predicted the co-current electric field predicted the distribution of MWCNTs. By applying a programmed light pattern, we successfully fabricated hydrogel nanocomposites in the shape of a VT logo and produced hydrogel nanocomposite sensors. The capabilities of printed hydrogel nanocomposite sensors were demonstrated through beam vibration sensing, proving its potential application in structural health monitoring. The fabricated sensors demonstrated the capability to track finger movements, indicating their potential for wearable sensing applications. In summary, this study offers a unique approach for nanocomposites fabricating multi-material integration and material anisotropy control, thereby facilitating advanced smart material development. Future work will focus on exploring the fabrication of hydrogels containing other types of nanomaterials to enhance material conductivity and achieve other functions, aiming with the goal of developing nanocomposite sensors for applications in soft robotics, biomedicine, structural health monitoring, and wearable sensing.
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Light‐Gated Manipulation of Micro/Nanoparticles in Electric Fields
The rapid development of micro/nanomanipulation technologies has opened unprecedented opportunities for the sorting, assembly, and actuation of biological and inorganic entities for applications ranging from live‐cell separation, drug screening, biosensing to micro/nanomachines and nanorobots. To this end, remarkable progress has been made in the development of efficient, precise, and versatile nanomanipulation techniques based on individual or combined chemical and physical fields. Among them, techniques that fuse light stimuli with electric (E) fields, have achieved impressive performance in the versatility, reconfigurability, and throughput in the manipulation of both biological and inorganic micro/nanoscale objects compared to those of many other manipulation techniques, by leveraging the strong optoelectric coupling effect of semiconductor materials. This work provides a review of various types of light‐gated electric manipulation systems – the working principles, experimental setups, limitations, applications, and future perspectives.
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- PAR ID:
- 10151353
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Advanced Intelligent Systems
- Volume:
- 2
- Issue:
- 7
- ISSN:
- 2640-4567
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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