A method for producing an amide compound from a nitrile compound using a biocatalyst by producing an amide compound aqueous solution having low foamability.

The present application discloses a method of delivering a protein drug into a cell, including utilization of a cationic lipid analog material. The cationic lipid analog material of the present application has an efficient intracellular delivery of a protein, and is effective for proteins of different molecular weights and charges. Moreover, the biological activity of the protein can still be maintained when the protein is delivered into the cell. At the same time, the ionizable cationic lipid analog material has low toxicity to cells and good biocompatibility, and can be used as delivery carriers for protein drugs.