A review on preparation methods and applications of metal-organic framework-based solid-phase microextraction coatings

Metal-organic frameworks have drawn increasing attention in the field of solid-phase microextraction due to their unique porous structure. Solid-phase microextraction coatings based on metal-organic frameworks exhibit large surface area (up to 1458 m2/g), high selectivity, stability (up to 270 extraction/desorption cycles), and extraction efficiency. Although there have been numerous studies on the synthesis of such fibers, many are not commercially available. In situ deposition from solution, chemical vapor deposition, electrodeposition, adhesion, sol-gel, and chemical bonding techniques are discussed among the methods reported to prepare coatings based on a metal-organic framework. Applications of these coatings for the measurement of volatile organic compounds, polycyclic aromatic hydrocarbons, persistent organic pollutants, phenols, and polychlorinated biphenyls are reviewed and critically discussed. The concluding remarks outline technical challenges and future potential of metal-organic framework based solid-phase microextraction fibers.