Oleic acid

ASD (95.23%, high-performance liquid chromatography purity) was a pilot product prepared by our laboratory. Its purity was calibrated by the standard substance purchased from the National Institutes for Food and Drug Control (Beijing, People’s Republic of China). Phospholipid (91.4% phosphatidylcholine) was purchased from Beijing Yuan Hua Mei Lecithin Sci-Tech Co., Ltd. (Beijing, People’s Republic of China). Labrafac Lipophile WL 1349, Labrafil M 1944 CS, Peceol (Glyceryl monooleate [type 40]), Maisine 35-1, Capryol 90, and Transcutol HP (Diethylene glycol monoethyl ether) were kindly supplied by Gattefossé (Saint-Priest Cedex, France). Olive oil, oleic acid, ethyl oleate, polyethylene glycol 400, and 1,2-propanediol were purchased from Nanjing Chemical Reagent Co., LTD. (Nanjing, People’s Republic of China). Polyoxyl 40 hydrogenated castor oil and Polyoxyl 35 castor oil were donated by BASF (Ludwigshafen, Germany). Diazepam (purity ≥98%) was purchased from Aladdin Industrial Corporation (Shanghai, People’s Republic of China). All the other chemicals were of analytical or chromatography grade.

NOR (purity >98%) was purchased from Chengdu Chroma Biotechnology Co., Ltd. (Chengdu, People's Republic of China). soybean phospholipid (95% phosphatidylcholine) was donated by Shanghai Avet Pharmaceutical Technology Co., Ltd. (Shanghai, People's Republic of China). Labrafac Lipophile WL1349, Labrafil M 1944 CS, Peceol, Capryol 90, Lauroylycol 90, Labrasol, and Transcutol HP (analytical purity) were kindly supplied by Gattefossé (Shanghai, People's Republic of China). Cremophor EL, Cremophor RH 40, and Solutol HS 15 (analytical purity) were donated by BASF (Shanghai, People's Republic of China). Oleic acid and tween 80 (analytical purity) were purchased from Nanjing Chemical Reagent Co., Ltd. (Nanjing, People's Republic of China). Ethyl oleate and MgCl₂ (analytical purity) were obtained from Sinopharm Chemical Reagent Co., Ltd. (Shanghai, People's Republic of China). UDPGA (purity >93%), D-Saccharic acid 1, 4-lactone (purity >98%), and alamethicin (purity >98%) were purchased from Sigma-Aldrich (St. Louis, MO, USA). BCA Protein Assay Kit was purchased from Nanjing Jiancheng Bioengineering Insitute (Nanjing, People's Republic of China). Sinomenine (purity >98%, internal standard) was purchased from Nanjing Jingzhu Bio-technology Co., Ltd. HPLC-grade acetonitrile was purchased from Merck (Darmstadt, German). All other chemicals and solvents were of analytical purity.