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Fernando Lima de Menezes

Bio: Fernando Lima de Menezes is an academic researcher from Federal University of Ceará. The author has contributed to research in topics: Nanoparticle & Lipase. The author has an hindex of 3, co-authored 8 publications receiving 52 citations.

Papers
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Journal ArticleDOI
TL;DR: The production of fatty acid ethyl ester (FAAE) from the free fatty acids of babassu oil catalyzed by lipase from Rhizomucor miehei immobilized on magnetic nanoparticles (MNP) coated with 3-aminopropyltriethoxysilane (APTES), Fe3O4@ APTES-RML or RML-MNP for short was evaluated.
Abstract: In this communication, it was evaluated the production of fatty acid ethyl ester (FAAE) from the free fatty acids of babassu oil catalyzed by lipase from Rhizomucor miehei (RML) immobilized on magnetic nanoparticles (MNP) coated with 3-aminopropyltriethoxysilane (APTES), Fe3O4@APTES-RML or RML-MNP for short. MNPs were prepared by co-precipitation coated with 3-aminopropyltriethoxysilane and used as a support to immobilize RML (immobilization yield: 94.7 ± 1.0%; biocatalyst activity: 341.3 ± 1.2 U p-NPB/g), which were also activated with glutaraldehyde and then used to immobilize RML (immobilization yield: 91.9 ± 0.2%; biocatalyst activity: 199.6 ± 3.5 U p-NPB/g). RML-MNP was characterized by X-Ray Powder Diffraction (XRPD), Fourier Transform-Infrared (FTIR) spectroscopy and Scanning Electron Microscope (SEM), proving the incorporation and immobilization of RML on the APTES matrix. In addition, the immobilized biocatalyst presented at 60°C a half-life 16-19 times greater than that of the soluble lipase in the pH range 5-10. RML and RML-MNP showed higher activity at pH 7; the immobilized enzyme was more active than the free enzyme in the pH range (5-10) analyzed. For the production of fatty acid ethyl ester, under optimal conditions [40°C, 6 h, 1:1 (FFAs/alcohol)] determined by the Taguchi method, it was possible to obtain conversion of 81.7 ± 0.7% using 5% of RML-MNP.

73 citations

Journal ArticleDOI
TL;DR: The use of a commercially available amino-phosphonate compound, diethylenetriaminepenta (methylene phosphonic acid, DTPMP), to functionalize Fe3O4 NPs to be potentially applied as MRI contrast agent presents a novel and excellent alternative magnetic material for biological and technological application.

21 citations

Journal ArticleDOI
TL;DR: In this article , the Taguchi method was used to obtain an IY of 97.1 ± 0.10% with a mass activity (AtD) of 83.81 ± 0 0.50 U/g for the hydrolysis of p -nitrophenyl butyrate.

19 citations

Journal ArticleDOI
24 Sep 2020
TL;DR: In this paper, a superparamagnetic polymer-based films using the biopolymeric matrices chitosan (Ch), cellulose (BC) and collagen (Col) was developed for microstrip antennas substrates.
Abstract: Magneto-dielectric composites are interesting advanced materials principally due to their potential applications in electronic fields, such as in microstrip antennas substrates. In this work, we developed superparamagnetic polymer-based films using the biopolymeric matrices chitosan (Ch), cellulose (BC) and collagen (Col). For this proposal, we synthesized superparamagnetic iron oxide nanoparticles (SPIONs) functionalized with polyethyleneimine with a cheap method using sonochemistry. Further, the SPIONs were dispersed into polymer matrices and the composites were evaluated regarding morphology, thermal, dielectric and magnetic properties and their application as microstrip antennas substrates. Microscopically, all tested films presented a uniform dispersion profile, principally due to polyethyleneimine coating. Under an operating frequency (fo) of 4.45 GHz, Ch, BC and Col-based SPION substrates showed moderate dielectric constant (e′) values in the range of 5.2–8.3, 6.7–8.4 and 5.9–9.1, respectively. Furthermore, the prepared films showed no hysteresis loop, thereby providing evidence of superparamagnetism. The microstrip antennas showed considerable bandwidths (3.37–6.34%) and a return loss lower than −10 dB. Besides, the fo were modulated according to the addition of SPIONs, varying in the range of 4.69–5.55, 4.63–5.18 and 4.93–5.44 GHz, for Ch, BC and Col-based substrates, respectively. Moreover, considering best modulation of e′ and fo, the Ch-based SPION film showed the most suitable profile as a microstrip antenna substrate.

9 citations


Cited by
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Journal ArticleDOI
TL;DR: It can be predicated that hybrid support materials, directed immobilization methods, site-directed mutagenesis, recombinant fusion protein technology and green nanomaterials and trailor-made supports will be used increasingly to produce more efficient immobilized industrial enzymes in near future.

85 citations

Journal ArticleDOI
TL;DR: This paper has focused on making suitable carriers for the immobilization of α-amylase from Bacillus subtilis and lipase from Candida rugosa via adsorption on modified Na-sepiolite (SEP).

60 citations

Journal ArticleDOI
31 May 2022-ACS Nano
TL;DR: In this article , a highly antiwater Znx-diethylenetriaminepenta (methylene-phosphonic acid) interface layer with good zinc affinity and a special nanoscaled 3D granular structure is designed on Zn metal to address the problems.
Abstract: Aqueous Zn metal batteries suffer from rapid cycling deterioration due to the severe water corrosion and dendrite growth on Zn anodes. Herein, a highly antiwater Znx-diethylenetriaminepenta(methylene-phosphonic acid) interface layer with good zinc affinity and special nanoscaled 3D granular structure is designed on Zn metal to address these problems. Experimental results combined with theoretical analysis and COMSOL simulations reveal that the hydrophobic groups in such Zn-based organic complex are the decisive factor in preventing H2O from damaging Zn anode surface. The massive Zn2+ attractive sites formed by interaction of methylene-phosphonic acid groups and Zn cause ion channel for fast zinc-ion adsorption and migration. And the developed nano granular architecture on the surface induces redistributed Zn2+ ion flux to realize homogenization with smooth and compact surface deposition. Under the synergism, such modified anodes exhibit long cycling lifespan over 1300 h with a relatively low polarization voltage at 5 mA cm-2. Also, the assembled full cells (including Zn//V2O5 and Zn//MnO2 cell) based on this anode are also demonstrated. The work provides a simple, low cost, and efficient pathway by combining the two concepts of structural design and constructing protective layers on the surface to prepare high-performance Zn anodes toward prospering aqueous zinc-metal batteries.

59 citations

Journal ArticleDOI
TL;DR: In this article, a review discusses the trending studies and industrial applications of the materials and protocols for lipase immobilization, analyzing their advantages and disadvantages, and summarizes the current challenges and potential alternatives for lipases at the industrial level.
Abstract: The market for industrial enzymes has witnessed constant growth, which is currently around 7% a year, projected to reach $10.5 billion in 2024. Lipases are hydrolase enzymes naturally responsible for triglyceride hydrolysis. They are the most expansively used industrial biocatalysts, with wide application in a broad range of industries. However, these biocatalytic processes are usually limited by the low stability of the enzyme, the half-life time, and the processes required to solve these problems are complex and lack application feasibility at the industrial scale. Emerging technologies create new materials for enzyme carriers and sophisticate the well-known immobilization principles to produce more robust, eco-friendlier, and cheaper biocatalysts. Therefore, this review discusses the trending studies and industrial applications of the materials and protocols for lipase immobilization, analyzing their advantages and disadvantages. Finally, it summarizes the current challenges and potential alternatives for lipases at the industrial level.

56 citations