Fiber coating based on a green metal-organic framework to determine phthalates in bottled waters by direct-immersion micro solid-phase extraction

The metal-organic framework CIM-80(Al) is proposed as sorbent coating for solid-phase microextraction fibers. The novel CIM-80(Al)-based microextraction fibers (SPME) with a thickness of only 3.5 µm were used to isolate and determine 14 phthalate esters in bottled water with potential results. To compare the extraction efficiency of this novel green material with commercially available SPME fibers, several parameters of the overall procedure were setup. Different parameters such as pH, stirring speed, adsorption and desorption time, salting effect, and percentage of organic solvents were optimized. The results obtained with the CIM-80(Al) based-SPME fibers are promising and comparable to commercial coatings. It demonstrates similar results in a total of 16 bottled water samples subjected to determination. The detection and quantification were performed using ultra-high performance liquid chromatography-tandem mass spectrometer (UHPLC-MS/MS). The effectiveness of the proposed method was corroborated by its analytical characteristics such as limits of detection, which ranged from 0.01 to 0.5 µg L−1 while the linear range was 0.04 to 1 000 µg L−1. In terms of recoveries, CIM-80(Al)-SPME fiber provided results from 70 to 107 %, while the precision of the method in terms of relative standard deviation varied from 1.8 to 18.8 %.