In view of the many advantages of solid-phase extraction over traditional liquid extraction, this technology is being increasingly applied in various fields including environmental analysis, food, pharmaceuticals, clinical research, and industrial production. The US Environmental Protection Agency has also included this in the analysis methods of many environmental pollutants. In recent years, the application of automated solid-phase extraction equipment in environmental analysis has also increased, with involvement in the analysis of environmental samples such as water, air, soil, and sediments.
The solid-phase extraction spe technology is widely used for the enrichment of trace organic pollutants in environmental water samples. In the 1980s, solid-phase extraction technology was widely used in the water quality monitoring of rivers such as the Songhua River, Huangpu River, and Taihu Lake (for the determination of halogenated hydrocarbons, chlorinated pesticides, chlorobenzene, chlorophenol, aniline, nitro compounds, polychlorinated biphenyls, polycyclic aromatic hydrocarbons, and phthalate esters, etc.). To extract organic compounds from water samples, the washing capacity of water should be weak, therefore, reverse-phase extraction is generally adopted for environmental water sample treatment.
Volatile substances account for 90% of environmental air pollutants, with the rest being particulate matter, which can be captured by filter membranes. Automated solid-phase extraction is generally used for volatile and semi-volatile substances, absorbance in solution or low-temperature condensation enrichment sampling. Air passes through the solid-phase extraction column at room temperature or low temperature, and the target organic compounds are retained in the column, while the normal components in the air, such as nitrogen, oxygen, pass through the small column and flow out. This extracts the target compounds directly from the air, and then through thermal analysis desorption and into the gas chromatograph for separation and quantitative analysis. Sample collection, separation, and enrichment of pollutants in air can be achieved by solid-phase extraction, which is convenient and fast.
SPE solid-phase extraction technology is mainly used for purification and enrichment in solid samples. Usually, the solid samples are first dissolved and extracted, and the extracted solution is purified by solid-phase extraction columns to further remove interfering substances and enrich the target analyte.
Researchers have applied accelerated solvent extraction and solid-phase extraction purification gas chromatography to determine polycyclic aromatic hydrocarbons and organic chlorine in soil. This method shortens the preprocessing time, improves purification efficiency, and has high accuracy and sensitivity. The method is simple and suitable for the analysis of batch soil samples.