title: Marangoni self-propelled capsules in a maze: pollutants 'sense and act' in complex channel environments.
abstract: Environmental remediation is a highly pressing issue in society. Here we demonstrate that autonomous self-propelled millimeter sized capsules can sense the presence of pollutants, mark sites for visible identification and remove the contamination, while navigating in a complex environment of interconnected channels, the maze. Such long-range self-powered capsules propelled by the Marangoni effect are capable of releasing chemicals to alter the pH and induce aggregation during pollutant flocculation at a faster rate than convection or diffusion. These devices are foreseen to have real-world environmental applications in the near future.
authors.affiliation: Division of Chemistry & Biological Chemistry, School of Physical and Mathematical Sciences Nanyang Technological University, 21 Nanyang Link, Singapore 637371, Singapore. pumera@ntu.edu.sg.
authors.forename: Guanjia
authors.initials: G
authors.lastname: Zhao
authors.forename: Martin
authors.initials: M
authors.lastname: Pumera
mesh_terms: D002214:Capsules; D011232:Chemical Precipitation; D004126:Dimethylformamide / Q000737:chemistry; D004735:Energy Transfer; D004784:Environmental Monitoring / Q000295:instrumentation*; D052918:Environmental Restoration and Remediation / Q000295:instrumentation*; D004867:Equipment Design; D005427:Flocculation; D006863:Hydrogen-Ion Concentration; D007093:Imidazoles / Q000737:chemistry; D008422:Materials Testing; D053768:Metal Nanoparticles / Q000737:chemistry; D046210:Microfluidic Analytical Techniques / Q000295:instrumentation*; D053769:Nanocapsules / Q000737:chemistry; D011108:Polymers / Q000737:chemistry; D066330:Printing, Three-Dimensional; D012967:Sodium Dodecyl Sulfate / Q000032:analysis* / Q000737:chemistry; D013450:Sulfones / Q000737:chemistry; D013501:Surface-Active Agents / Q000032:analysis* / Q000737:chemistry; D014741:Video Recording; D014873:Water Pollutants / Q000032:analysis* / Q000037:antagonists & inhibitors / Q000737:chemistry
chemical_list: D002214:Capsules; D007093:Imidazoles; D053769:Nanocapsules; D011108:Polymers; D013450:Sulfones; D013501:Surface-Active Agents; D014873:Water Pollutants; C017662:polysulfone P 1700; D012967:Sodium Dodecyl Sulfate; C029899:imidazole; D004126:Dimethylformamide