Fantastic Voyage of Nanomotors into the Cell

Abstract

Richard Feynman’s 1959 vision of controlling devices at small scales and swallowing the surgeon has inspired the science-fiction Fantastic Voyage film and has played a crucial role in the rapid development of the microrobotics field. Sixty years later, we are currently witnessing a dramatic progress in this field, with artificial micro- and nanoscale robots moving within confined spaces, down to the cellular level, and performing a wide range of biomedical applications within the cellular interior while addressing the limitations of common passive nanosystems. In this review article, we discuss key recent advances in the field of micro/nanomotors toward important cellular applications. Specifically, we outline the distinct capabilities of nanoscale motors for such cellular applications and illustrate how the active movement of nanomotors leads to distinct advantages of rapid cell penetration, accelerated intracellular sensing, and effective intracellular delivery toward enhanced therapeutic efficiencies. We finalize by discussing the future prospects and key challenges that such micromotor technology face toward implementing practical intracellular applications. By increasing our knowledge of nanomotors’ cell entry and of their behavior within the intracellular space, and by successfully addressing key challenges, we expect that next-generation nanomotors will lead to exciting advances toward cell-based diagnostics and therapy.

Medical Micro/Nanorobots in Precision Medicine

“…[283][284][285][286] The external spatiotemporal control and active manipulation of micro/nanorobots inside living cells have permitted to unprecedented access to the biophysical fundamentals going from gene expression or dynamic mechanical mapping of the intracellular environment to drug delivery and sensing. [287] Ultrasound powered microrobots have demonstrated the ability to internalize and propel inside individual living cells. This capability has been used to deliver genetic material inside cells.…”

Nanomotors Sense Local Physicochemical Heterogeneities in Tumor Microenvironments**

“…While previous work has been done to study the interaction between 3D cell culture-nanomotor while the motors penetrated the cells [50] or 3D spheroids using chemi-Angewandte cally powered nanomotors [51][52][53][54][55][56] and acoustically propelled microdrills, [57,58] here we look at the interaction of the nanomotors with the cancer modified microenvironment. We consider the molecular mechanism by which the nanomotors adhere to the cancer microenvironment is through electrostatic,t hat is,c harge-based interactions.T he cancer microenvironment is abundant in sugar-conjugated molecules,which are present both on cell surfaces (and form their brushes) and in the ECM.…”

A Journey of Nanomotors for Targeted Cancer Therapy: Principles, Challenges, and a Critical Review of the State‐of‐the‐Art

“…To close this section, and to direct readers to sources of information beyond this current review, we list the following excellent review articles on nanomotors for biomedical applications, on the topics of 1) overall overviews, [36,[72][73][74][75] 2) drug delivery/cargo transportation, [32,34,38,40,[76][77][78][79][80][81] 3) diagnosis, [82] 4) sensing, [77][78][79]83] 5) in vivo applications, [34,[84][85][86] 6) surface coating, [87] 7) cancer therapy, [33,37,88,89] 8) biocompatibility, [66] 9) biological barriers/complex environment/entering a cell [39,[90][91][92] and 10) imaging, [90,93,94] as well as on particular types of nanomotors for biomedical application, such as those made of hydrogel [95] or those powered by magnetic fields. [96] This list of review articles-a total of 35 and counting-is by no means comprehensive, and only covers the period of 2013-2020 (see the book by Prof. Joseph Wang [7] for pre-2013 reviews).…”