Polymeric membrane supports in electromembrane extraction: An overview of various options, methodologies, and modifications

Electromembrane extraction (EME) has emerged as a novel, versatile and efficient approach for sample preparation, widely applied across various scientific fields. Given the economic and industrial drive for maximum efficiency, the membrane in EME systems, a crucial part of the process, has been extensively studied. This has led to the development of multiple membrane formats, fabrication techniques, and modification approaches. The introduction and application of novel EME systems are particularly highlighted for complex analytes or samples, where maximum purification, recovery or elimination is desired. Additionally, EME offers significant advantages in reducing operation time and cost, making it particularly valuable in addressing environmental concerns. This review summarises the various membrane options, such as hollow fibers, flat sheets, polymer inclusions, and gel membranes, discussing their conventional fabrication methods with an emphasis on the advantages and general specifications of each. Furthermore, the review explores membrane modification approaches for improving EME performance, including solvent and polymeric support modifications, outlining specific applications, benefits, and future prospects. Challenges and limitations of these membrane options are also discussed.