Fabrication and application of a MIL-68(In)-NH₂ incorporated high internal phase emulsion polymeric monolith as a solid phase extraction adsorbent in triazine herbicide residue analysis

In this work, a metal-organic framework MIL-68(In)-NH₂ incorporated high internal phase emulsion polymeric monolith (MIL-68(In)-NH₂/polyHIPE) was prepared and applied as a solid phase extraction adsorbent for the extraction and detection of trace triazine herbicides in environmental water samples by coupling with HPLC-UV detection. The fabricated material showed good adsorption for simazine, prometryn, and prometon in water samples because of π-π interactions and hydrogen bonding interactions. Under optimal conditions, the maximum adsorption capacity of simazine, prometon and prometryn was 800 μg g^-1, 800 μg g^-1 and 6.01 mg g^-1, respectively. The linearities were 10-800 ng mL^-1 for simazine, prometon and prometryn. The limits of detection were 31-97 ng L^-1, and the recoveries were 85.6-118.2% at four spiked levels with relative standard deviations lower than 5.0%. The method has a high sensitivity for the determination of three triazine herbicides in environmental water samples.