Abstract The electrodialysis of pure rac-ibuprofen and the products of the enzymatic kinetic resolution of the profen were investigated in order to establish the best conditions for the separation of the ibuprofen from the ethyl esters. The enzymatic esterification of rac-ibuprofen with ethanol (used as solvent and acyl-aceptor) was catalyzed with Novozym®435 at the optimum conditions investigated previously. The reaction product mixtures possess about 60% of ibuprofen (enriched in the S-enantiomer) and 40% of the racemic esters. An electrodialysis cell composed by four compartments separated by cation-, anion- and cation-exchange membranes was developed allowing the selective migration of ibuprofen avoiding its decomposition on the electrodes. In fact, the stainless steel electrodes submerged in ammonium formate solutions were separated from the compartments containing the profen (∼200 ppm in ethanol, pH 6.81–6.34) with cation-exchange membranes. The best separation performance was reached after 6 h of operation at 60 V with an anion-exchange membrane that led up to 57% extraction of ibuprofen from the products of the enzymatic esterification in ethanol media. The membrane allowed the selective migration of both stereoisomers and a negligible quantity of the ethyl esters.

中文翻译：

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通过电渗析分离布洛芬对映体和外消旋酯

摘要 对纯外消旋布洛芬的电渗析及其酶动力学拆分产物进行了研究，以建立布洛芬与乙酯分离的最佳条件。在先前研究的最佳条件下，使用 Novozym®435 催化外消旋布洛芬与乙醇（用作溶剂和酰基受体）的酶促酯化。反应产物混合物含有约 60% 的布洛芬（富含 S-对映异构体）和 40% 的外消旋酯。开发了由阳离子交换膜、阴离子交换膜和阳离子交换膜分隔的四个隔室组成的电渗析池，允许布洛芬选择性迁移，避免其在电极上分解。实际上，浸没在甲酸铵溶液中的不锈钢电极与含有 profen（乙醇中约 200 ppm，pH 6.81-6.34）的隔室用阳离子交换膜隔开。使用阴离子交换膜在 60 V 下运行 6 小时后达到最佳分离性能，该膜可从乙醇介质中的酶促酯化产物中提取高达 57% 的布洛芬。该膜允许两种立体异构体和可忽略量的乙酯的选择性迁移。