The use of solid sorbents for direct accumulation of organic compounds from water matrices–a review of solid‐phase extraction techniques

Abstract

The main principles of solid‐phase extraction techniques are reviewed in this paper. Various solid sorbents can be used as a suitable trap for direct accumulation of organic compounds from aqueous solutions. The trapped analytes can be desorbed by elution with suitably chosen liquid phases. These preconcentration procedures can be considered as low performance liquid chromatography and the efficiency of the procedure can thus be related to the retention characteristics of the preconcentration column. The main sorbents used for trace enrichment purposes are also reviewed. Besides, the concise methodology, sample storage, and automation are discussed. The advantages of solid phase extraction as compared to liquid‐liquid extraction are given as well as some drawbacks of this method.

Analyte isolation by solid phase extraction (SPE) on silica-bonded phases: Classification and recommended practices (Technical Report)

“…The silica-bonded phases used in solid phase extraction are similar to those used in liquid chromatography (LC), except that the mean particle sizes of the silicas are different: for SPE irregularly particles with a particle diameter ranging between 30 and 60 pm is used [5], whereas the silica for HPLC usually has a particle diameter of 3 to 10 pm and can be irregular or spherical in shape.…”

“…For the extraction of pesticides from water matrices on 100 mg C18 sorbent, developed by Junk and Richard [36], flow rates as high as 250 mumin could be employed in the adsorption step, without any effect on the recoveries : they stated that the small particle size and the high surface area of the C18 phase ensured a good contact between the analytes and the octadecyl functional group, even at high flow rates. On the contrary, other authors claim that the flow rate can have an influence on the recoveries, because both the adsorption and elution steps involve an equilibrium process between the solid phase and the analyte [1, 5,11]. At higher flow rates, nonequilibrium conditions may exist, which ultimately result in lower recoveries, lower breakthrough volumes and larger elution volumes.…”

“…The capacity depends on the type of solid phase wed and the bed volume and is related with the analyte's retention, which in turn is dependent on the solvents or matrix the analyte is dissolved in [5,6]. Estimates of the column capacity of silica bonded phases lie in the mg/g range.…”

“…[10,22]. As the concentration of analytes extracted from pharmaceutical, biomedical, environmental or food material usually lie in the ng/mL or pg/mL range, the capacities of the available sorbent quantities should be sufficient for most applications, even with all matrix interferences that can, together with the analyte, be adsorbed [5,6,10,37]. Choosing a larger sorbent mass (1 g instead of 100 mg for instance) can be of interest if large volumes need to be extracted (e.g., measurement of organic compounds in waste water) or to compensate for a weak affaty of a solid phase for the analyte [4].…”

Avaliação Da Presença De Pesticidas N-Metilcarbamatos E Seus Produtos De Degradação Nas Águas Da Região De Pará De Minas (Mg) Brasil

“…A técnica de extração em fase sólida (SPE) tem sido empregada para concentrar diferentes pesticidas presentes em amostras de água (20,(22)(23)(24).…”