Absolute methanol

Here, 2-MIL (41.06 mg; MilliporeSigma, St. Louis, MO, USA) was dissolved in 10 mL of absolute methanol to form 2-MIL solution (50 mmol·L⁻¹). Then, 74.37 mg of Zn(NO₃)₂·6H₂O (MilliporeSigma) was dissolved in 10 mL of absolute methanol to form Zn(NO₃)₂ solution (25 mmol·L⁻¹). These two solutions were mixed together at room temperature, kept stationary for 1 h, and spun at 7 000 r.p.m. for 10 min. The white precipitation was ZIF-8 after supernatant was removed. ZIF-8 precipitation was washed with absolute methanol (Sinopharm, Shanghai, China) for three times, then dispersed in 4 mL of absolute methanol for further use.

Methyl laurate (99%), methyl myristate (98%), methyl palmitate (99.5%), methyl stearate (97%), triethylenetetramine (60%) and dimethyl carbonate (99.5%) were purchased from J&K Scientific Ltd. Toluene (99.5%), sodium hydroxide (85%), formic acid (98%), acetic acid (99.5%), lactic acid (85%), absolute ethanol (99.7%), absolute methanol (99.5%) and absolute ethyl ether (99.7%) were provided by Sinopharm Chemical Reagent Beijing Co., Ltd. Acetonitrile (99%) was obtained from an Beijing HWRK Chemical Reagent Co., Ltd. Nutrient broth was supplied by Beijing OBO Biotech Co., Ltd. Benzalkonium chloride solution (50 g l⁻¹) was purchased from Beijing Derun Pharmaceutical Co., Ltd. Pseudomonas aeruginosa, Escherichia coli, Staphylococcus aureus and Bacillus subtilis were obtained from an environmental professional laboratory. The high-purity water (ρ = 18.25 MΩ cm⁻¹) was supplied by an ultrapure laboratory water purification system. N,N,N′,N′-tetramethyl-N,N′-di(2-laurylamideethyl) ethylenediamine methyl carbonate, N,N,N′,N′-tetramethyl-N,N′-di(2-myristylamideethyl) ethylenediamine methyl carbonate and N,N,N′,N′-tetramethyl-N, N′-di(2-palmitylamideethyl) ethylenediamine methyl carbonate (purity greater than 98%) were prepared according to a green method reported in our previous paper [20 (link)].