Ultra-fast and selective extraction of phenolic acids by multifunctional and magnetic nanomaterials in honeysuckle

Novel multifunctional magnetic nanomaterials were developed for ultra-fast and selective extraction of phenolic acids across a wide pH range. The magnetic core was firstly coated with SiO₂, followed by surface modification with 4-vinylphenylboronic acid (VPBA), 1-vinylimidazole (VI) and methacrylamido propyl trimethyl ammonium chloride (MAPTAC) as functional monomers. The characterization, repeatability, adsorption kinetics, and adsorption isotherms were investigated, and five different phenolic acids were used to demonstrate its selectivity. A maximum adsorption capacity of 86.58 mg/g was determined by the Langmuir adsorption model. The limits of detection and quantification of the method were 0.01 μg/mL and 0.04 μg/mL, respectively. The experimental results exhibited that the resultant multifunctional nanomaterials had satisfactory magnetic property, fast kinetics, favorable adsorption capacity, excellent specificity and higher repeatability. The Fe₃O₄@MPS-SPE exhibited ultra-fast kinetics with a complete adsorption of 2 s and a wide pH range of 3∼8. The multifunctional magnetic nanomaterials were successfully used as sorbents for selective extraction of phenolic acids in honeysuckle.