1. DA-a macromolecular cross-linker with functional degree 2-was prepared through the structural modification of PF127 with acryloyl chloride at the end group (Fig. S3a). The Fourier transform infrared (FTIR) spectrum of PF127-DA exhibited a new infrared absorption peak at 1724 cm -1 after the functional modification of PF127, which corresponded to the stretching vibration of the C=O acrylate structure (Fig. S3b and S3c). Furthermore, the proton nuclear magnetic resonance ( 1 H NMR) spectra exhibited characteristic peaks of acrylate double bonds with chemical shifts of 6.47 and 5.87 ppm, which confirmed the successful synthesis of PF127-DA. Micelle formation was also detected;Hyaluronic acid is abundant in reactive groups
2. Conductivities of epidermis, dermis, and subcutaneous tissue at intermediate frequencies;K Wake;Physics in medicine and biology,2016