Abstract
Owing to their high surface area, stability, and functional groups on the surface, iron oxide hydroxide nanoparticles have attracted attention as enzymatic support. In this work, a chemometric approach was performed, aiming at the optimization of the horseradish peroxidase (HRP) immobilization process on Δ-FeOOH nanoparticles (NPs). The enzyme/NPs ratio (X1), pH (X2), temperature (X3), and time (X4) were the independent variables analyzed, and immobilized enzyme activity was the response variable (Y). The effects of the factors were studied using a factorial design at two levels (−1 and 1). The biocatalyst obtained was evaluated for the ferulic acid (FA) removal, a pollutant model. The materials were characterized by X-ray powder diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), and scanning electron microscopy (SEM). The SEM images indicated changes in material morphology. The independent variables X1 (−0.57), X2 (0.71), and X4 (0.42) presented the significance effects estimate. The variable combinations resulted in two significance effects estimates, X1*X2 (−0.57) and X2*X4 (0.39). The immobilized HRP by optimized conditions (X1 = 1/63 (enzyme/NPs ratio, X2 = pH 8, X4 = 60 °C, and 30 min) showed high efficiency for FA oxidation (82%).
Highlights
Chemistry can be considered a fundamental science for sustainable development, possible processes that lead to the production of less waste, reducing the generation of toxic effluents
The X-ray diffraction (XRD) results indicated that the particles of ∆-FeOOH were synthesized as a dominant phase
The iron oxides mixed may occur as a result of the similar crystallization profile, and the octahedron hexagonal rings of Fe+3 possibly replace the isoforms during the formation of crystals, resulting different phases of FeOOH [26]
Summary
Chemistry can be considered a fundamental science for sustainable development, possible processes that lead to the production of less waste, reducing the generation of toxic effluents. Horseradish peroxidase has a versatile application, and it is highlighted in the wastewater remediation, containing dyes, amines, and phenolic compounds [5,6,7,8,9]. This enzyme catalyzes the conversion of organic compounds in the presence of hydrogen peroxide, producing phenoxy radicals. These radicals react with each other, forming water-insoluble polymers, possible to separate by sedimentation [5,10]. Thereby, the facilitated separation of enzymes becomes an issue indispensable for advantageous processes, what can be reached by the enzymatic immobilization
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
