Microextraction Techniques as a Sample Preparation Step for Metal Analysis

Recent Microextraction Techniques for Determination and Chemical Speciation of Selenium

“…To attain a high enrichment factor, the time to reach equilibrium should be short. It is also important to select a fi ber material of suitable polarity; the fi ber material that is the most eff ective for SPME and is readily available is polydimethylsiloxane (PDMS) [1]. Temperature is another important factor aff ecting SPME.…”

“…Longer extraction times are usually recommended in order to ensure complete extraction. After sample extraction is achieved for a certain analyte, then the extract is introduced to a suitable instrument for determination [1]. Therefore, the process of eluting the analyte from the fi ber and the time elution takes should be optimized.…”

“…The strength and time of sonication and magnetic stirring also should be optimized and considered. Lastly, the salt content that controls the ionic strength and hence analyte volatility also should be investigated [1].…”

“…Recently developed ME methods have been applied to a variety of purposes and are intended to produce high-quality results and high enrichment factors using simple, automated, and inexpensive methods. At the same time, they follow principles of green chemistry in that they use very small amounts (microliter volumes) of organic solvents [1]. Twenty-six years ago, microextraction techniques were established.…”

“…One form of ME, liquid phase microextraction (LPME), was introduced by Rezaee et al [2], and a second form, solid phase microextraction (SPME), was introduced by Arthur and Pawliszyn [3]. Within these two classifications of ME, there are many subclasses of techniques with different modes and equipment used for preconcentration and separation [1].…”