Iron 3 chloride

Glucose oxidase (GOx, from Aspergillus niger), chitosan, single-walled carbon nanotubes, iron(III) chloride, potassium ferricyanide(III), and 5% Nafion solution were purchased from Macklin. Acetic acid (2%), potassium chloride, and PBS (pH 7.2) were purchased from Aladdin, and 100 μm thick PI film was purchased from McMaster-Carr. All reagents were used as received.

Enzymatic hydrolysis lignin (EHL) was acquired from Hong Kong Laihe Biotechnology Co., Ltd. (Hong Kong, China) The hydroxyl content, the number-average molecular mass, and polydispersity of EHL are 2.67 mmol/g, 1430 g/mol, and 1.22, respectively. Doxorubicin hydrochloride was purchased from Shanghai Macklin Biochemical Co., Ltd. (Shanghai, China) Purity is higher than 98%. Tetrahydrofuran (THF) of analytical-grade purity was provided by Beijing Chemical Reagent Company (Beijing, China). Folic acid was supplied by Chembase Co., Ltd. (Shanghai, China) Iron (II) chloride tetrahydrate and Iron (III) chloride and albumin from bovine serum were purchased from Shanghai Macklin Biochemical Co., Ltd. (Shanghai, China) Poly (dimethyl diallyl ammonium chloride) solution (PDAC, Mw < 100,000, 35 wt.% in water, 100–200 CP (25 °C)) was provided by Shanghai Aladdin Bio-Chem Technology Co., Ltd. (Shanghai, China).

Hyaluronic acid (HA) with a molecular weight of 400 kDa was purchased from Tianjin Xiensaopude Technology Co., Ltd (Tianjin, China). Sodium ascorbate was purchased from Shanghai Meryer Chemical Technology Co., Ltd. (Shanghai, China). N-Hydroxysuccinimide (NHS) was purchased from Shanghai Yuanye Bio-Technology Co., Ltd. (Shanghai, China). 1-Ethyl-(3-dimethylaminopropyl) carbodiimide hydrochloride (EDC) was purchased from Shanghai Bide Pharmaceutical Technology Co., Ltd. (Shanghai, China). Manganese chloride anhydrous was purchased from Energy Chemical (Anqing, China). Zinc chloride, iron(III) chloride, and dopamine hydrochloride were purchased from Macklin (Shanghai, China). TRIS was purchased from Solarbio (Beijing, China). Phosphate-buffered saline (PBS) was purchased from Gibco (Grand Island, NY, USA). C-FOS antibody was purchased from Abcam (Cambridge, UK). Fluorescein isothiocyanate (FITC)-labeled secondary antibody and calcium ion fluorescence probe Fluo-4 AM were purchased from Biyuntian Biotechnology Co., Ltd. (Shanghai, China). Rat pheochromocytoma cell line (PC12) was purchased from KeyGen BioTECH (Nanjing, China). The indium tin oxide-coated polyethylene terephthalate (ITO-PET) film was purchased from South China Xiangcheng Technology Co., Ltd. (Yiyang, China). The polyimide film was purchased from Shenzhen Zhenpai Adhesive Co., Ltd. (Shenzhen, China).