Hybrid biomembrane–functionalized nanorobots for concurrent removal of pathogenic bacteria and toxins

Abstract

With the rapid advancement of robotic research, it becomes increasingly interesting and important to develop biomimetic micro-or nanorobots that translate biological principles into robotic systems. We report the design, construction, and evaluation of a dual-cell membrane-functionalized nanorobot for multipurpose removal of biological threat agents, particularly concurrent targeting and neutralization of pathogenic bacteria and toxins. Specifically, we demonstrated ultrasound-propelled biomimetic nanorobots consisting of gold nanowires cloaked with a hybrid of red blood cell (RBC) membranes and platelet (PL) membranes. Such hybrid cell membranes have a variety of functional proteins associated with human RBCs and PLs, which give the nanorobots a number of attractive biological capabilities, including adhesion and binding to PL-adhering pathogens (e.g., Staphylococcus aureus bacteria) and neutralization of pore-forming toxins (e.g., -toxin). In addition, the biomimetic nanorobots displayed rapid and efficient prolonged acoustic propulsion in whole blood, with no apparent biofouling, and mimicked the movement of natural motile cells. This propulsion enhanced the binding and detoxification efficiency of the robots against pathogens and toxins. Overall, coupling these diverse biological functions of hybrid cell membranes with the fuel-free propulsion of the nanorobots resulted in a dynamic robotic system for efficient isolation and simultaneous removal of different biological threats, an important step toward the creation of a broad-spectrum detoxification robotic platform.

Micro/Nanomachines: from Functionalization to Sensing and Removal

“…It is exemplified that such nanomotors can effectively adsorb Shiga toxin and bind to platelet‐adhering pathogens (Figure o), which dramatically expand the scope of biomedical nanorobotic operations in physiological systems and offer new opportunities to nanomedicine. Consequently, the cell membrane–camouflaged biofunctionalization makes the micro/nanomachines more biocompatible and has highly complex functionalities necessary for effective biointerfacing, opening the door to the design and development of bioinspired micro/nanomotors with robust functionalities and diverse applications …”

“…During the past years, considerable advances on detoxification have been made by using micro/nanomachines coated with desired functional materials. Wang and co‐workers reported ultrasound‐propelled biomimetic nanorobots composed of gold nanowires cloaked with a hybrid of RBC membranes and PL membranes (Figure l) . Due to plenty of functional proteins associated with human RBCs and PLs, such functionalized nanorobots displayed a number of attractive biological capabilities, including adhesion and binding to PL‐adhering pathogens (e.g., Staphylococcus aureus bacteria) and neutralization of pore‐forming toxins (e.g., α‐toxin) (Figure m).…”

“…p) SEM image and microscopic images of a Staphylococcus aureus (MRSA) USA300 bacterium attached to an RBC–PL robot. Panels (l) to (p) reproduced with permission . Copyright 2018, American Association for the Advancement of Science.…”

Nano/Micromotors for Diagnosis and Therapy of Cancer and Infectious Diseases

“…SEM images showed the specific micromotor binding with MRSA USA300 bacteria. Micromotors were further explored for the selective binding with methicillin‐resistant Staphylococcus aureus …”

A Macrophage–Magnesium Hybrid Biomotor: Fabrication and Characterization

“…The development of artificial micromotors that can convert energy to movement and forces has recently become a fascinating research area . Improvements in the biocompatibility of the micromotor's materials have allowed them to perform some biomedical tasks, such as targeted drug delivery, precise surgery, biosensing, or toxin removal . Among the different types of biocompatible micromotors, Mg‐based Janus micromotors offer distinct advantages for in vivo applications owing to their autonomous propulsion in body fluids including gastric and intestinal fluids, cargo transport and release, and their transient biodegradability properties .…”