The using of layer-by-layer assembly polyelectrolyte (PE) films has been suggested as a new versatile technique for surface modification aimed at tissue engineering and cell-based chips. In this study, we investigated the surface morphology of the hyaluronic acid (HA)-based PE films deposited on the amino-functionalized glass slides using atomic force microscopy. These thin films (bilayer number <9) were measured to have nanoscale roughness ranging from 10 to 100 nm. Then the primary hippocampal and cortical neural cells were cultured on the PE films, respectively. After 5 days of culturing, the cytocompatibility to neural cells was evaluated by cellular morphology, neurite outgrowth, and microtubule-associated protein 2 expressions. From the present results, the HA-based PE films were found to be able to support neural cell adhesion and neurite development, especially for the polycation-ending films. It is suggested these HA-based multilayer PE films or similar build-ups could thus be used in the future as a way to modify surfaces for nerve scaffolds and neuron-based chips.

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Sonodynamic therapy (SDT) is a non‐invasive therapeutic modality with high tissue‐penetration depth to induce reactive oxygen species (ROS) generation for tumor treatment. However, the clinical translation of SDT is restricted seriously by the lack of high‐performance sonosensitizers. Herein, the distinct single atom iron (Fe)‐doped graphitic‐phase carbon nitride (C3N4) semiconductor nanosheets (Fe‐C3N4 NSs) are designed and engineered as chemoreactive sonosensitizers to effectively separate the electrons (e−) and holes (h+) pairs, achieving high yields of ROS generation against melanoma upon ultrasound (US) activation. Especially, the single atom Fe doping not only substantially elevates the separation efficiency of the e−‐h+ pairs involved in SDT, but also can serve as high‐performance peroxidase mimetic enzyme to catalyze the Fenton reaction for generating abundant hydroxyl radicals, therefore synergistically augmenting the curative effect mediated by SDT. As verified by density functional theory simulation, the doping of Fe atom significantly promotes the charge redistribution in the C3N4‐based NSs, which improves their synergistic SDT/chemodynamic activities. Both the in vitro and in vivo assays demonstrate that Fe‐C3N4 NSs feature an outstanding antitumor effect by aggrandizing the sono‐chemodynamic effect. This work illustrates a unique single‐atom doping strategy for ameliorating the sonosensitizers, and also effectively expands the innovative anticancer‐therapeutic applications of semiconductor‐based inorganic sonosensitizers.