Water-In-oil Emulsion Liquid Membrane Transport of L-Cysteine
Water-In-oil Emulsion Liquid Membrane Transport of L-Cysteine
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DOI：
10.1080/01496395.2012.675001
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发表时间：
2013-01
影响因子：
2.8
通讯作者：
S. Fathi;M. Yaftian;A. Kargari
中科院分区：
文献类型：
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作者：
S. Fathi;M. Yaftian;A. Kargari
研究了氯化钾溶液中 L-半胱氨酸 (L-cys) 通过含有二环己基-18-冠-6 (CE) 的乳液液膜的转运。传输机制基于 (K·CE)+ 复合物和 L-cys- 之间的离子对形成。考察并讨论了影响该过程的参数，即外相pH、载体浓度、接收相浓度、乳化和搅拌速度的影响。通过将进料相的离子强度调整为 0.01 M 和 pH 10（KCl/KOH 混合物），实现了 L-半胱氨酸（1 × 10−4 M）运输的最高性能。该膜是通过冠醚 (6 × 10−4 M)、4% 乳化剂 (ECA-4360) 和液体石蜡的混合物乳化（11000 rpm）制备的。乳液球的最佳有机物与水的体积比和处理比分别为1:3和0.1。使用盐酸溶液(2M)作为反萃相。 30分钟后提取步骤完成。通过搅拌各相（700 rpm）。该过程对 L-半胱氨酸对 L-色氨酸、L-酪氨酸、L-亮氨酸、L-蛋氨酸、L-精氨酸、L-天冬酰胺、L-天冬氨酸、L-甘氨酸、L-丝氨酸和 L-苏氨酸表现出优异的选择性。紫外可见分光光度计。采用光谱法和薄层色谱法，以茚三酮为指示剂，进行氨基酸分析。
Transport of L-cysteine (L-cys) from potassium chloride solutions through emulsion liquid membranes containing dicyclohexyl-18-crown-6 (CE) has been investigated. The mechanism of transport is based on ion-pair formation between (K · CE)+ complex and L-cys-. The effect of parameters influencing the process, that is, pH of the external phase, carrier concentration, receiving phase concentration, emulsification, and stirring speed were examined and discussed. The highest performance for transport of L-cysteine (1 × 10−4 M) was achieved by adjusting the ionic strength of the feed phase at 0.01 M and pH 10 (KCl/KOH mixture). The membrane was prepared by emulsification (at 11000 rpm) of the mixture of crown ether (6 × 10−4 M), 4% emulsifier (ECA-4360) and liquid paraffin. The optimized organic to aqueous volume ratio of the emulsion globules and treat ratio was found to be 1:3 and 0.1, respectively. Hydrochloric acid solution (2 M) was used as stripping phase. The extraction step was completed after 30 min. by stirring the phases (700 rpm). The process shows an excellent selectivity towards L-cysteine with respect to amino acids L-tryptophan, L-tyrosine, L-leucine, L-methionine, L-arginine, L-asparagine, L-aspartic acid, L-glycine, L-serine, and L-threonine. UV-Vis. Spectroscopy and TLC method using ninhydrin, as indicator, were used for amino acids analysis.