Magnetic mesoporous polyimide composite for efficient extraction of Rhodamine B in food samples.

Area of Science:

• Materials Science
• Analytical Chemistry
• Nanotechnology

Background:

• Magnetic solid-phase extraction (MSPE) is a powerful technique for sample preparation.
• Developing novel magnetic sorbent materials with high efficiency and selectivity is crucial for MSPE.
• Polyimide-based composites offer unique properties for adsorption applications.

Purpose of the Study:

• To synthesize and characterize a core-shell structured magnetic polyimide composite.
• To evaluate its performance as a sorbent material for magnetic solid-phase extraction (MSPE) of rhodamine B.
• To optimize the MSPE method and apply it for the determination of rhodamine B in food samples.

Main Methods:

• Core-shell magnetic polyimide composite synthesis via covalent coating of mesoporous polyimide onto magnetite nanoparticles.
• Characterization using SEM, TEM, N2 adsorption-desorption, XRD, FTIR, and VSM.
• Optimization of MSPE parameters using response surface methodology (RSM).
• Determination of rhodamine B in food samples (hot pepper, red wine, chili powder).

Main Results:

• The synthesized composite exhibited a large surface area (306.45 m²/g), a specific pore size (2.15 nm), and strong magnetic properties (45.7 emu/g).
• Optimized MSPE method achieved high extraction efficiency for rhodamine B.
• Successful determination of rhodamine B in real food samples with recoveries ranging from 94.8% to 103.3% and relative standard deviations <5.5%.

Conclusions:

• The magnetic polyimide composite is a highly effective and promising sorbent for MSPE.
• The adsorption mechanism involves multiple interactions, including hydrophobic, π-π, and hydrogen bonding.
• The developed method provides a sensitive and reliable approach for detecting rhodamine B in food matrices.