Living Magnetotactic Microrobots Based on Bacteria with a Surface-Displayed CRISPR/Cas12a System for Penaeus Viruses Detection

Abstract

Bacterial microrobots are an emerging living material in the field of diagnostics. However, it is an important challenge to make bacterial microrobots with both controlled motility and specific functions. Herein, magnetically driven diagnostic bacterial microrobots are prepared by standardized and modular synthetic biology methods. To ensure mobility, the Mms6 protein is displayed on the surface of bacteria and is exploited for magnetic biomineralization. This gives the bacterial microrobot the ability to cruise flexibly and rapidly with a magnetization intensity up to about 18.65 emu g–1. To achieve the diagnostic function, the Cas12a protein is displayed on the bacterial surface and is used for aquatic pathogen nucleic acid detection. This allows the bacterial microrobot to achieve sensitive, rapid, and accurate on-site nucleic acid detection, with detection limits of 8 copies μL–1 for decapod iridescent virus 1 (DIV1) and 7 copies μL–1 for white spot syndrome virus (WSSV). In particular, the diagnostic results based on the bacterial microrobots remained consistent with the gold standard test results when tested on shrimp tissue. This approach is a flexible and customizable strategy for building bacterial microrobots, providing a reliable and versatile solution for the design of bacterial microrobots.

A Nanorobotics-Based Approach of Breast Cancer in the Nanotechnology Era

“…Cell-based microrobots, such as erythrocytes, sperm cells [100], leukocytes and other motile cells driven microrobots, are considered effective for targeted drug delivery, due to their escape mechanisms and biocompatibility [98]. Magnetic bacteria-based bio-hybrid microrobots are a widely used living material in the field of magnetically driven diagnostics [101] as well as for targeted cancer therapy [102]. Microalgae, due to their high biocompatibility, low costs, large active surface area, strong anti-cancer drug and NPs absorption capability, phototaxis, oxygen production and high-speed of propulsion, can be successfully used as oxygenators, micro-or nanoswimmers and ideal carriers for efficient drug loading and precise targeted DDS [99,103].…”

Bio-Hybrid Magnetic Robots: From Bioengineering to Targeted Therapy

“…Additionally, microbial surface display technologies can be employed to exhibit other proteins for diverse functions. For instance, the Mms6 protein is displayed on the bacterial surface to facilitate magnetite bio-mineralization [108]. This approach presents a flexible and customizable strategy for constructing bacteria-based robots, offering a reliable and versatile solution for their design.…”

Roadmap for Clinical Translation of Mobile Microrobotics

“…[22] As a preventive healthcare tool, they could help clinicians as vaccination carrier agents, [23] early diagnostic tools for preventable diseases by continuous monitoring of health parameters, [24] and rapid point-of-care cellular marker screening devices. [21,25] In incurable medical conditions, including retinal blindness and neurodegenerative diseases, the microrobots could be functional to carry nano-or micro-scale stimulators to the targeted tissues. [26,27] These microrobots can deliver electrical or chemical stimuli to specific areas of the nervous system, including the retina, nuclei of the brain, or spinal cord, to modulate neural activity and promote functional recovery.…”