Synthesis of triethylene tetramine-modified water-insoluble corn flour caged in magnetic chitosan resin and its adsorption application for removal of patulin from apple juice

In this study, triethylene tetramine-modified water-insoluble corn flour caged in magnetic chitosan resin (TETA-WICF/MCR) was firstly prepared, which indicates novel aspects for immobilization and chemically modification of mycotoxin adsorbents. The TETA-WICF/MCR was characterized using zoom stereo microscope, scanning electron microscopy (SEM), Fourier transform infrared (FTIR) spectroscopy, X-ray diffractometer (XRD), and magnetic separation performance analysis. Experimental results confirmed successful layer by layer modification of chitosan, biosorbent water-insoluble corn flour (WICF), TETA onto the surface of magnetic beads. The mean diameter of the TETA-WICF/MCR was 2.63 mm with good magnetic-responsive ability. Subsequently, the adsorption performance of the TETA-WICF/MCR obtained toward patulin was assessed in batch adsorption system and the results demonstrated that the adsorption process was strongly depended on adsorbent dosage, contact time, temperature, and initial patulin concentration. The results of SEM images and FTIR analysis showed obvious changes in the porous structure of TETA-WICF/MCR after adsorbing patulin, and -NH2 and -OH groups were predominantly involved in the adsorption of patulin. Furthermore, the adsorption kinetics followed the mechanism of pseudo-second-order model, and equilibrium data were well fitted in the Freundlich isotherm model. It was also found that the TETA-WICF/MCR had good reusability without any adverse changes in apple juice. Practical Application Patulin is a regulated toxin biosynthesized by certain fungi that contaminate agricultural commodities, such as fruits, juices, and other beverages. Several approaches have been studied to reduce patulin levels in apple juice and other aqueous systems. There is need for more low-cost and eco-friendly adsorbent capable of detoxifying patulin contaminated. In this sense, triethylene tetramine-modified water-insoluble corn flour caged in magnetic chitosan resin (TETA-WICF/MCR) was first prepared and exhibits easy solid-liquid separation and high adsorption capacity for removing patulin from contaminated apple juice.