Biocompatible propulsion for biomedical micro/nano robotics

Abstract

Micro/Nano robots have shown enormous potential for diverse biomedical applications, such as targeted delivery, in vivo biosensing, minimally invasive surgery and cell manipulation through extending their area of operation to various previously inaccessible locations. The motion of these small-scale robots can be either self-propelled or remotely controlled by some external power sources. However, in order to use them for biomedical applications, optimization of biocompatible propulsion and precise controllability are highly desirable. In this article, the recent progresses about the biocompatible propulsion (e.g. self-propulsion, external stimuli based propulsion and bio-hybrid propulsion) techniques for these micro/nano robotic devices are summarized along with their applications, with a special focus on the advantages and disadvantages of different propulsion techniques. The current challenges and future perspectives of these small-scale devices are discussed in the final section. Highlights This review paper discusses: • The enormous potential of micro/nano robotics for advancing biomedical applications. • The latest development of the biocompatible propulsion techniques. • The future research needed to prompt the widespread adoption of micro/nano robotics in the biomedical sector.

Light‐Powered Microrobots: Challenges and Opportunities for Hard and Soft Responsive Microswimmers

“…Although light is generally considered to be an actuator suitable for biological applications, [ 184 ] a thorough biocompatibility study is necessary for each individual optical control configuration, as specific combinations of wavelength and power can have different effects on cells, tissues, or bodily fluids. Typically, nIR light is considered safe for biological entities, provided that the power used is not too high, as it is the case for optical trapping setups.…”

“…A recent study showed that to reduce potential inflammatory responses, the microrobot design should minimize any physical interactions with the cells of the immune system while improving the locomotion performance of the microrobots. [183] Although light is generally considered to be an actuator suitable for biological applications, [184] a thorough biocompatibility study is necessary for each individual optical control configuration, as specific combinations of wavelength and power can have different effects on cells, tissues, or bodily fluids. Typically, nIR light is considered safe for biological entities, provided that the power used is not too high, as it is the case for optical trapping setups.…”

Engineering Intelligent Nanosystems for Enhanced Medical Imaging

“…Similarly, bubble‐mediated propulsion of nano‐ and micromotors, as discussed in the previous section, may be advantageous in tissue deconstruction as well. [ 187–189 ] Kagan et al demonstrated PFC‐loaded microbullets capable of tissue penetration, as well as inducing tissue expansion and splicing under acoustic droplet vaporization (Figure 9C). [ 187 ] The incorporation of photothermal agents in PFC droplets allows for optical droplet vaporization by laser light, which could be advantageous for photoacoustic imaging.…”

Enzyme catalysis powered micro/nanomotors for biomedical applications

“…The mimicking of natural motility behaviour using synthetic soft materials has been discussed by Samuel Sanchez et al 26 The biocompatibility of propulsion techniques has been discussed by Halder and Sun. 27 Several reviews towards biomedical applications have also been published. In 2018, Guan et al discussed the use of micro/nanorobots for active drug delivery.…”