Fig. 4: Characterization of the buoyancy drive unit in the BDS-gel.
From: A self-regulating shuttle for autonomous seek and destroy of microplastics from wastewater
a Overview of the preparation procedure for the buoyancy drive unit of the BDS-gels. b Mode of operation of the buoyancy drive during the ascending process (left) and the descending process (right). When T < LCST of pNIPAM, the BDS-gel swells and absorbs glucose into its pores. The drive unit within the pores then converts the glucose into oxygen, which is stored in the NOPs. When T > LCST of pNIPAM, the BDS-gel collapses, and the polymer chains become more hydrophobic. This, combined with the expansion of the gas due to increased temperatures, facilitates the expulsion of the gas bubbles, thereby deactivating the buoyancy. c TEM micrograph of the Pt-NP/GOx functionalized NOPs (scale bar = 50 nm). This is part of a tomography shown in Supplementary Fig. S3c. d UV-Vis study of the enzymatic activity of GOx functionalized NOPs at different temperatures. e Photographs of the ascending process of the shuttle gel at different time intervals (hh:mm:ss:ms). f Comparison of the ascent time and speed of various shuttle gels in relation to the platinum concentration (determined from Supplementary Movie S1).
