G7x mark 2

At the end of the experiment, the Petri dish was photographed with a high-resolution camera (Canon G7X Mark II, Tokyo, Japan), and the above-ground part was harvested, weighed, and extracted with 5.0 mL of 80 percent acetone to measure chlorophyll-a (Chl-a), chlorophyll-b (Chl-b), and carotenoid concentrations [24 ]. ImageJ software was used to convert the photos to an 8-bit RGB format, which was then used by SmartRoot software to assess the total root length (TRL) [25 (link),26 (link)].

With the help of a homebuilt wire loop (diameter: ~28 mm), CYTOP nanosheets can be lifted out of water and supported in the air. The specimen was gently placed in the center of a coverslip with a diameter of 25 mm (0.13–0.16 mm thickness, AS ONE Co., Japan), and then wrapped with a nanosheet. To test the bearing capacity of a nanosheet, a round magnetic tape (diameter: 10 mm, thickness: 0.5 mm, KOKUYO Co., Ltd. Japan) was used as a model tissue and wrapped with a CYTOP nanosheet. A permanent magnet cylinder (diameter: 10 mm, thickness: 10 mm, remanence magnetic flux density: 480 mT) was approached from a distance of 10 mm with a speed of 2.0 mm min^–1 until the nanosheet ruptured. This process was performed on a horizontal universal testing machine and the force was recorded by a digital force gauge (FSA-0.5HK2 and ZTA-2N, IMADA Co., Ltd. Japan). The photos of the nanosheet wrapping process, the nanosheet wrapped agarose gel and brain slice were taken using a digital camera G7 X Mark II (Canon Inc., Japan). The photos of the mechanical test were captured using a portable microscopy (3R-MSUSB401, 3R SOLUTION Co., Japan).