An Overview of Micronanoswarms for Biomedical Applications

Abstract

Micronanoswarms have attracted extensive attention worldwide due to their great promise in biomedical applications. The collective behaviors among thousands, or even millions, of tiny active agents indicate immense potential for benefiting the progress of clinical therapeutic and diagnostic methods. In recent years, with the development of smart materials, remote actuation modalities, and automatic control strategies, the motion dexterity, environmental adaptability, and functionality versatility of micronanoswarms are improved. Swarms can thus be designed as dexterous platforms inside living bodies to perform a multitude of tasks related to healthcare. Existing surveys summarize the design, functionalization, and biomedical applications of micronanorobots and the actuation and motion control strategies of micronanoswarms. This review presents the recent progress of micronanoswarms, aiming for biomedical applications. The recent advances on structural design of artificial, living, and hybrid micronanoswarms are summarized, and the biomedical applications that could be tackled using micronanoswarms are introduced, such as targeted drug delivery, hyperthermia, imaging and sensing, and thrombolysis. Moreover, potential challenges and promising trends of future developments are discussed. It is envisioned that the future success of these promising tools will have a significant impact on clinical treatment.

Magnetic Microrobotic Swarms in Fluid Suspensions

“…Although swarms have been navigated in vivo with vision feedback [23,55], the current imaging modalities, such as fluorescence imaging, photoacoustic imaging, MRI, US, and X-ray fluoroscopy, still have limitations. Specifically, the fluorescence imaging and photoacoustic imaging can only be used for swarm localization in shallow [3]. When using MRI, image artifacts caused by magnetic materials have negative impacts on the accurate position tracking of swarms [56].…”

“…The swarms are formed by thousands or even millions of small individual agents [2]. Tasks that are challenging for single agent can be accomplished by swarms collectively, such as targeted delivery and hyperthermia [3]. The imaging contrast is enhanced by using the swarms, benefiting the image-guided navigation and manipulation [4].…”

“…With effective automatic control methods, the swarms can be propelled to move following desired trajectories [13]. Different imaging modalities, such as magnetic resonance imaging (MRI) [14], fluorescence imaging [15], and ultrasound imaging (US) [16], allow the swarms to be detected in vivo, and biomedical applications can be accomplished [3].…”

A Flexible, Mechanically Strong, and Anti‐Corrosion Electromagnetic Wave Absorption Composite Film with Periodic Electroconductive Patterns

“…The ACP film had a certain degree of transparency with a transmittance of 3.5% at 595 nm, which was better than other reported EMW response films (Figure 1d). [41,42] The fluorine-containing groups in the framework (4,4′-(hexafluoroisopropylidene) diphthalic anhydride [6FDA] and 4,4′-oxydianiline [ODA] systems), as well as the removal of the CM hard template, were responsible for the improved transparency (Figure S10, Supporting Information). [43]…”

Magnetic Microswarm and Fluoroscopy‐Guided Platform for Biofilm Eradication in Biliary Stents

“…[18][19][20] Various external fields such as magnetic, [21][22][23][24][25] light, [26][27][28] electric, [29,30] and ultrasonic fields [31,32] can be employed to trigger and control the formation and locomotion of microrobotic swarms, among which magnetic field-driven microrobotic swarms are more attractive due to their untethered and precise control and harmlessness to humans. [33][34][35][36][37] In recent years, the multimodal modulation, controlled micromanipulation, and adaptive motion properties of magnetically driven microrobot swarms have been extensively studied, [21,[38][39][40] and show the value in practical applications such as thrombus removal, [41][42][43] environmental remediation, [44,45] etc. ; however, magnetically driven microrobotic swarms for bacterial biofilm eradication have not been fully investigated.…”