Δ-FeOOH as Support for Immobilization Peroxidase: Optimization via a Chemometric Approach

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%).

A Non‐enzymatic Ag/δ‐FeOOH Sensor for Hydrogen Peroxide Determination using Disposable Carbon‐based Electrochemical Cells

“…The sharp peak at 497 cm À 1 was assigned to the AgÀ Ag framework deposited on FeOOH. The infrared bands observed in FeOOH and Ag/FeOOH were in good agreement with the literature [20]. The SEM micrograph of δ-FeOOH (Figure 1c) A) shows a nonhomogeneous plate nanoarchitecture of 100-160 nm width.…”

Theoretical Studies Aimed at Finding FLT3 Inhibitors and a Promising Compound and Molecular Pattern with Dual Aurora B/FLT3 Activity

“…ii) Other compounds also interacted with Asp829 residue through different groups: N-imidazolidinone (37, 41); amidic carbonyl (9,20); NH between pyridinone and indolinone groups (26, 29); and amidic carbonyl located next to the terminal benzene (12, 18, 27) 12, 18, 23, 27 and 33 interacted with Glu661 through the -NH group located between two acyclic carbonyls.…”

“…A population of individuals is exposed to competitive selection that weeds out poor solutions. Recombination and mutation are used to create new solutions [15][16][17][18][19][20][21][22].…”

Immobilization of Low-Cost Alternative Vegetable Peroxidase (Raphanus sativus L. peroxidase): Choice of Support/Technique and Characterization

“…Calcium alginate microspheres also were used as organic support for enzyme immobilization due to be material of easy synthesis, inexpensive and non-toxic [42][43][44]. Inorganic supports of distinct chemical natures have been applied for enzymes immobilization, such as iron hydroxyl oxide [45] and silica [31]. Among inorganic supports the materials silica-based are the most usual choices [31] due to large pore volume, high surface area, high thermal stability and mechanical resistance [28,46].…”