L valine

SCAAs (Cys, CySS, GSH, and HCys), 1,4-benzoquinone (pBQ), 3-mercaptopropionic acid (3-MPA), PR, BPR, PV, and other amino acids [L–alanine (Ala), L–arginine (Arg), L–aspartic acid (Asp), L–glutamine (Gln), L–glutamic acid (Gln), glycine (Gly), L–histidine (His), L–isoleucine (Ile), L–leucine (Leu), L–lysine (Lys), L–methionine (Met), L–phenylalanine (Phe), L–proline (Pro), L–serine (Ser), L–threonine (Thr), L–tryptophan (Trp), L–tyrosine (Tyr), and L–valine (Val)] were purchased from Tokyo Chemical Industries Co. Inc. (Tokyo, Japan). Additionally, ARS, sodium chloride, methanol, and zinc nitrate hexahydrate were purchased from FUJIFILM Wako Pure Chemical Co. Inc. (Osaka, Japan). N-(2-hydroxyethyl)-1-piperazineethanesulfonic acid (HEPES) was purchased from Dojindo Laboratories (Kumamoto, Japan). All chemicals were used without further purification. All aqueous samples were prepared with Milli-Q water (18.2 MΩcm) (Millipore, Bedford, MA, United States).

DL-leucine and decyl alcohol were obtained from Acros Organics (98+% Fair Lawn, NJ, USA). L-methionine, L-lysine, and D-aspartic acid were obtained from Sigma Chemical Co. (St. Louis, MO, USA). DL-tryptophan, L-arginine, and DL-serine were obtained from Eastman Organic Chemicals (New York, NY, USA). L-phenylalanine was obtained from Sigma-Aldrich (St. Louis, MO, USA). DL-alanine, L-glutamic acid, hydrochloric acid, chloroform, acetonitrile, and L-tyrosine were obtained from Fisher Scientific Company (Fair Lawn, NJ, USA). L-proline and L-valine were obtained from Tokyo Chemical Industry (Oregon, USA). L-cysteine was obtained from Alfa Aesar (Heysham, England). L-histidine, ethanol, and methanol were obtained from Aldrich Chemical Co. (Milwaukee, WI, USA).