Norfloxacin

Water-compatible commercial molecularly imprinted polymers (MIPs) material, named SupelMIP^TM SPE-Fluoroquinolones, was purchased from Sigma–Aldrich (St.Louis, MO, USA). Fe₃O₄ magnetite nanocomposites (MNPs) were prepared according to previous studies^{46 (link),66 (link)} (detailed in Supplementary). Fluoroquinolones (norfloxacin, enoxacin, and fleroxacin, purity 98%) were purchased from J&K Scientific Ltd. (Shanghai, China). The individual stock solutions of norfloxacin, enoxacin, and fleroxacin were prepared in methanol at a concentration of 0.1 mg mL⁻¹ and stored at 4 °C before use. Both Methanol and acetonitrile were HPLC grade and purchased from Merck KGaA (Darmstadt, Germany). Ammonium hydroxide solution (suitability for use in UPLC/LC-MS, NH₃, w/w 20%) was bought from CNW Technologies GmbH (Düsseldorf, Germany). Ethylene glycol, ethylene diamine, ferric trichloride hexahydrate (FeCl₃·6H₂O), and sodium acetate (NaAc) were purchased from Sinopharm Chemical Reagent Co. Ltd. (Shanghai, China). Ultrapure water obtained from a Millipore water purification system (Milli-Q, Millipore; Bedford, MA, USA).

A Nafion-117 cation exchange membrane for separating catholyte and anolyte was manufactured by Du Pont de Nemours & Co., Ltd. (Wilmington, DE, USA). A potentiostat providing direct current (DC) power was purchased from Shanghai Chenhua Science Technology Corp., Ltd., Shanghai, China. Unless otherwise specified, all chemical reagents were acquired from commercial suppliers and utilized without further purification. Sodium persulfate (PS, ≥99.5%), carbamazepine, norfloxacin, atrazine, phonel, methanol (99%), bisphenol A (BPA), sodium hydroxide (NaOH), atrazine, sulfuric acid (H₂SO₄), sodium sulfate (Na₂SO₄, ≥99.0%), Diammonium 2,2′-azino-bis (3-ethylbenzothiazoline-6-sulfonate) (ABTS), potassium titanium (IV) oxalate, tert-butanol (TBA, 99%), and boron-doped diamond electrode (BDD) electrodes (800 ppm boron, bipolar, 1 mm coating thickness) were obtained from J&K Chemical (Beijing, China). Activated carbon fiber (ACF) electrodes and platinum-plated titanium electrodes (25 mm × 50 mm × 1 mm) were obtained from Shanxi Kaida Chemical Ltd., Lvliang, China. DC power supply was obtained from Zhejiang Sako Electrical Group Co., Ltd., Leqing, China.

Norfloxacin was purchased from J&K chemical, Beijing, China. All other reagents were of reagent grade and were used without further purification. [^99mTc]NaTcO₄ was obtained from a ⁹⁹Mo/^99mTc generator purchased from Atomic High Tech Co. Ltd., Beijing, China. NMR spectra were recorded on a 400 MHz and 600 MHz JNM-ECS spectrophotometer (JEOL, Tokyo, Japan). ESI-MS spectra were recorded on an LC–MS Shimadzu 2010 series. HPLC analysis was performed on a Waters 2489 UV system and a Gabi raytest radioactivity detector using an analytical column (C-18, Kromasil, 100–5 μm, 250 × 4.6 mm). The centrifuge model was 800-1 (Ronghua, Jintan, China). The radioactivity was measured by WIZARD2 2480 Automatic Gamma Counter (PerkinElmer, Waltham, MA, USA), an HRS-2000 technetium analyzer (Huaruisen, Beijing, China), and RW-905A radioactivity meter (Hechang, Beijing, China). SPECT/CT imaging was performed on micro SPECT/CT equipment with 930 collimator (Trifoil, Chatswort, CA, USA). The SPECT technical parameters were as follows: native resolution ≤ 1.6 mm; detection area ≥ 128 mm × 128 mm; and sensitivity ≥ 4800 cps/MBq. Animal studies were performed in accordance with the Regulations on Laboratory Animals of Beijing Municipality and the guidelines of the Ethics Committee of Beijing Normal University (permit no. CLS-EAW-2018-001, June 2018).