α lactose

Avermectin B₂ technical material (TC, 95%, w/w), EC (5%, w/w), emulsion in water (EW, 2.5%, w/w) and water dispersible granule (WDG, 3.5%, w/w) were provided by Hebei Xingbai Agricultural Technology Co., Ltd. (Hebei, China). Sodium benzoate, α-lactose, glucose and sucrose were purchased from Sinopharm Chemical Reagent Co., Ltd. (Shanghai, China). Styryl phenol polyoxyethylene ether (emulsifier 600) and alkylphenol formaldehyde resin polyoxyethylene ether (emulsifier 700) were provided by Cangzhou Hongyuan Agrochemical Co., Ltd. (Hebei, China). Ethyl acetate, chromatographic grade methanol and acetonitrile were bought from J&K Scientific Ltd. (Beijing, China). Parafilm was purchased from Sigma-Aldrich Shanghai Trading Co., Ltd. (Shanghai, China). All the chemicals were used as received. Milli-Q water (18.2 MΩ.cm, TOC ≤ 4 ppb) was used in all analytical experiments.

TMB, β-lactose, ascorbic acid and uric acid were purchased from Aladdin Reagent Co. Ltd. (China). Glucose, sucrose and galactose were purchased from Sigma-Aldrich Chemical Co. (USA). GOx was purchased from J & K Chemical Ltd. (China). All other reagents were of analytical grade and obtained from Sinopharm Chemical Reagent co. Ltd. (China), such as KMnO₄, α-lactose and H₂O₂. Ultrapure water used in this experiment was obtained from a Millipore water purification system (Milli-Q). The absorption signals in this experiment were measured by microplate reader (Spectra Max M5, Molecular Devices).