Onion‐like Multifunctional Microtrap Vehicles for Attraction–Trapping–Destruction of Biological Threats

Abstract

A multifunctional motile microtrap is developed that is capable of autonomously attracting, trapping, and destroying pathogens by controlled chemoattractant and therapeutic agent release. The onion‐inspired multi‐layer structure contains a magnesium engine core and inner chemoattractant and therapeutic layers. Upon chemical propulsion, the magnesium core is depleted, resulting in a hollow structure that exposes the inner layers and serves as structural trap. The sequential dissolution and autonomous release of the chemoattractant and killing agents result in long‐range chemotactic attraction, trapping, and destruction of motile pathogens. The dissolved chemoattractant (l‐serine) significantly increases the accumulation and capture of motile pathogens (E. coli) within the microtrap structure, while the internal release of silver ions (Ag+) leads to lysis of the pathogen accumulated within the microtrap cavity.

Medical Micro/Nanorobots in Precision Medicine

“…The microrobot released a chemoattractant which permitted the dynamic approx-imation of motile pathogens to the microrobot, and the subsequent release of silver which destroyed the motile pathogen. [253] Although scientists have made great demonstrations of micro/nanomotor in targeted delivery, more work on the design aspects toward improving the selectivity and specificity, navigation in biologically relevant environments, controlled cargo release, real-time-tracking, and feedback should be conducted for successful in vivo application. All these platforms will foresee a great potential because they could come as a valuable tool for cancer therapy, regenerative medicine, and life extension therapy.…”

“…The microrobot released a chemoattractant which permitted the dynamic approximation of motile pathogens to the microrobot, and the subsequent release of silver which destroyed the motile pathogen. [ 253 ]…”

“…Moreover, the inner layer released a chemoattractant (serine) that served to attract nearby motile microorganisms and capture E. coli within the microtrap structure (Figure 8c). [ 253 ] These examples demonstrate the potential of microrobotic devices for biopsy and sample collection. However, the main challenge that these applications face is the ability to preserve the specimen and avoid contamination.…”

Dual‐Propelled Lanbiotic Based Janus Micromotors for Selective Inactivation of Bacterial Biofilms

“…[12] In am ore sophisticated configuration, Wangsg roup encapsulated serine as chemoattractant into Mg/Ag coated micromotors.A fter the Mg core dissolution, Escherichia Coli bacteria was attracted into the micromotor shell for enhanced contact with the Ag ions and accelerated killing. [13] Besides silver,T iO 2 have been coated in Mg spheres for lighttriggered ROS generation for Bacillus Globigii spores deactivation. [14] While effective,t he short lifetime of Mg and Ag layers in the above mentioned configurations hampers the prolonged use of such micromotors as well as the removal after treatment.…”

Dual‐Propelled Lanbiotic Based Janus Micromotors for Selective Inactivation of Bacterial Biofilms

“…In a more sophisticated configuration, Wang's group encapsulated serine as chemoattractant into Mg/Ag coated micromotors. After the Mg core dissolution, Escherichia Coli bacteria was attracted into the micromotor shell for enhanced contact with the Ag ions and accelerated killing [13] . Besides silver, TiO 2 have been coated in Mg spheres for light‐triggered ROS generation for Bacillus Globigii spores deactivation [14] .…”