Prospects for analytical pervaporation

As shown above, pervaporation is a useful analytical tool that features simplicity, and automation and miniaturization capabilities [195-197]. The actual potential of this technique for the pretreatment of solid, liquid and slurry samples can readily be inferred from its intrinsic features and from available methods using a pervaporator. 

Consolidation of this technique as an effective, widespread analytical tool is bound to rely on future, sequential developments such as the following (a) the gathering of sufficient research experience to compile a cookbook of methods where potential users can search for solutions to specific problems and (b) the commercialization of inexpensive pervaporation modules meeting the requirements of a variety of samples and analytes. The development of such methods and theoretical studies should turn pervaporation into a useful tool for routine environmental, clinical, food and industrial analyses. 

Solid-phase extraction (SPE) is one of the most commonly used sorbent extraction techniques. The analytes are extracted together with interfering compounds with some similar characteristics by passing a usually aqueous sample through a plastic cartridge containing dispersed sorbent on a particulate support. A selective organic solvent is normally used to remove interferences and a different solvent is then employed to elute the retained analytes. This technique has a number of attractive features as compared with traditional solvent extraction. Thus, it is quite simple and inexpensive, can be automated and used in the field, and uses relatively small amounts of solvents. Particle-load 

Because SPME is a static extraction technique, the need for a large surface area is no longer as critical as in SPE. Smooth liquid coatings can be used that avoid plugging. Also, by sampling from headspace, SPME can extract analytes from highly complex matrices such as sludge. 

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