Acetonitrile

Acetone, n-hexane, ethyl acetate, concentrated sulfuric acid, sodium hydroxide, phosphoric acid, acetonitrile, ascorbic acid, methanol, formic acid, sodium acetate, acetic acid, hydrochloric acid, iron(III) chloride hexahydrate solution, ammonium acetate, were purchased from Guangzhou Chemical Reagent Factory (Guangzhou, China). phenolic compound standards [rutin (Rut), quercetin (Que), quercitrin (Quer), isoquercitrin (Iso), chlorogenic acid (ChA), syringic acid (SyA), ferulic acid (FeA), caffeic acid (CaA), resveratrol (Res), epicatechin (Epi), astragalin (Ast), scopoletin (Sco), galangal (Gal), catechuic acid (CatA), vanillic acid (VaA), benzoic acid (BeA), gallic acid (GaA), and protocatechuic acid (PrA)] were purchased from the National Institutes for Food and Drug Control (Beijing, China). 2,4,6-tris(2-pyridyl)-S-triazine (TPTZ), 1,1-diphenyl-2-picrylhydrazyl (DPPH), 2,2ʹ-Azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) diammonium salt (ABTS), and 6-hydroxy-2,5,7,8-tetramethylchroman-2-carboxylic acid (trolox) were purchased from Sigma-Aldrich (St. Louis, MO, USA).

The fluopyram standard was purchased from the Environmental Protection Monitoring Institute of the Ministry of Agriculture of China at a concentration of 1000 mg/L. Analytical grade acetonitrile, acetone, dichloromethane, and sodium chloride were purchased from the Guangzhou Chemical Reagent Factory. Chromatographic grade Methanol and n-hexane were available from Thermo Fisher Scientific. Purified water was prepared using a Milli-Q reverse osmosis system (Millipore, Milford, MA, USA). Strata Florisil (FL-PR) 500 mg/6 mL SPE manufactured by Strata™ (5.0 mL n-hexane–acetone (9:1, V/V) solution pre-rinsing cartridge).
A standard solution of 1000 μg/mL fluopyram was diluted in n-hexane, and the matrix extract of the blank sample was obtained by the extraction method. The matrix standard solutions of 0.025, 0.05, 0.10, 0.15 and 0.50 μg/mL were obtained by the step dilution. All prepared solutions were stored at temperature of 4 °C until further use.

Mycoplasma gallisepticum strain S6 was obtained from the Chinese Veterinary Microorganism Culture Collection Center (Beijing, China). Culture media consisted of M. gallisepticum artificial medium base (Qingdao Hope Biological Technology) containing nicotinamide adenine dinucleotide and cysteine and swine serum (Guangzhou Ruite Biological) as previously described (3 (link)). Tilmicosin phosphate was a kind gift of Eastern Along Pharmaceuticals (Guangdong, China). Acetonitrile, formic acid, methanol (high-performance liquid chromatography grade), and remaining analytical grade reagents were purchased from Guangzhou Chemical Reagent.