Chemistry

Materials science

Electrochemistry

Electrode

Nanotechnology

Organic chemistry

Physical chemistry

ACS Nano

Self-propelled micro- and nanomachines are at the forefront of materials research, branching into applications in biomedical science and environmental remediation. Cationic frameworks enabling the collection and delivery of anionic species (A–) are highly required, due to the large variety of life-threatening pollutants, such as radioactive technetium and carcinogenic chromium, and medicines, such as dexamethasone derivatives with negative charges. However, such autonomous moving carriers for active transport of the anions have been barely discussed. A polymeric viologen (PV++)—consisting of electroactive bicationic subunits—is utilized in a tubular autonomous microswimmer to selectively deliver A– of different sizes and charge densities. The cargo loading is based on a facile anion exchange mechanism. The packed crystal structure of PV++ allows removal of an exceptionally high quantity of anions per one microswimmer (2.55 × 10–13 mol anions per microswimmer), a critical factor often neglected regarding the r...

Active Anion Delivery by Self-Propelled Microswimmers