Rhodamine b

Curcumin, lecithin, PBS (pH 7.4), Dulbecco's modified Eagle's medium (DMEM), 0.25% trypsin-EDTA, heat-inactivated FBS, and Dimethyl sulfoxide (DMSO) were purchased from Solarbio Life Sciences (Beijing, China). Chitosan (CS), perfluorohexane (PFH), Tween 20, Sephadex G-50, and dialysis membranes (MWCO: 12,000) were purchased from Muke Biotech (Zhejiang, China). Rhodamine B waspurchased from Sangon Biotech (Shanghai, China). Arg-Gly-Asp-l-Phe-Lys (RGDfk), N-hydroxysulfosuccinimide (sulfo-NHS), N-(3-dimethylaminopropyl)-N′-ethylcarbodiimide hydrochloride (EDC-HCl), and 3-(4,5)-dimethylthiahiazo (-z-y1)-3,5-di-phenytetrazolium-romide (MTT) were from Sigma-Aldrich (MO, USA). Other chemicals and solvents were obtained commercially of high-performance liquid chromatography (HPLC) or analytical grade. MDA-MB-231 breast cancer cells were from the Cell Bank of the Chinese Academy of Sciences in Shanghai.

We directly dissolved L012 (Wako Pure Chemical Industries, Ltd., Osaka, Japan) and 1,10-phenanthroline (Sinopharm Co., Shanghai, China) in ultrapure water to prepare a 4 mM stock solution. Luminol (Sigma-Aldrich) and ABEI (TCI, Tokyo, Japan) were respectively dissolved in NaOH (pH 12) solution to prepare 4 mM stock solutions. Next, 2-imidazolidinetione, 2-methyl-3-thiosemicarbazide, and pyrogallic acid were purchased from Shanghai Acmec Biochemical Co., Ltd. (Shanghai, China). Catechin was purchased from Solarbio (Beijing, China). Dopamine was purchased from J&K Scientific (Beijing, China); DMPO was purchased from Dojindo Molecular Technologies, Inc. (Kumamoto, Japan); and fluorescein and rhodamine B were purchased from Sangon Biotech (Shanghai, China). H₂O₂ was prepared fresh daily from 30% (vol/vol) H₂O₂ (Xinke Electrochemical Reagent Factory, Bengbu, China). All other reagents were obtained from Sinopharm Co. (Shanghai, China), of analytical grade. Ultrapure water was prepared by a Milli-Q system (Millipore, France) and used throughout.

Sulfamethazine-specific aptamer, SMZ1S (5′-CGTTAGACG-3′), was screened in our laboratory.23 (link) HAuCl₄·4H₂O, SMZ, sulfadimethoxine, sulfameter and nitrofurantoin were obtained from Sigma-Aldrich (St. Louis, MO, USA). Sulfapyridine, ofloxacin, chlortetracycline, doxycycline and chloramphenicol were purchased from Aladdin Biotechnology Inc. (Shanghai, China). Rhodamine B was obtained from Sangon Biotechnology Inc (Shanghai, China). Unless otherwise mentioned, all other reagents were of analytical grade. Ultrapure water was used for all experiments and obtained using a Millipore Milli-Q system (Millipore, Bedford, MA, USA).