Chitosan and gum arabic nanoparticles for heavy metal adsorption

Abreu, Flávia Oliveira Monteiro da Silva; Silva, Nilvan Alves da; Sipauba, Mateus de Sousa; Pires, Tamara Fernandes Marques; Bomfim, Tatiana Araújo; Monteiro, Oyrton Azevedo de Castro; Forte, Maria Madalena de Camargo

doi:10.1590/0104-1428.02317

Cited by 26 publications

(21 citation statements)

References 40 publications

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“…Therefore, the band at 1645 cm −1 , indicative of the C=N functional groups, allowed the confirmation of the reaction between the carbonyl groups of vanillin (C=O) and the amino groups (–NH 2 ) of CH [ 52 ]. Additionally, in the 1590–1610 cm −1 interval, no bands related to the bending vibrations of the CH or the typical vibratory stretching of the symmetric band of the –COO − functional group of the GA were observed, as reported by other authors [ 27 , 46 , 50 ]. This suggests that the electrostatic interaction of the –NH 2 and –COO − functional groups was carried out and, therefore, the formation of the CCs was achieved.…”

Section: Resultssupporting

confidence: 81%

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Microencapsulation of Vanilla Oleoresin (V. planifolia Andrews) by Complex Coacervation and Spray Drying: Physicochemical and Microstructural Characterization

Hernández-Fernández

García-Pinilla

Ocampo-Salinas

et al. 2020

Foods

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Vanilla is one of the most popular species in the world. Its main compound, vanillin, is responsible for its characteristic aroma and flavor and its antioxidant and biological properties. Vanillin is very unstable in the presence of oxygen, light, and humidity, which complicates its use and preservation. Therefore, to solve this problem, this study aimed to develop vanilla oleoresin microcapsules. Vanilla oleoresin was obtained with supercritical carbon dioxide and microencapsulated by complex coacervation and subsequent spray drying (100 °C/60 °C inlet/outlet temperature). The optimal conditions for the complex coacervation process were 0.34% chitosan, 1.7% gum Arabic, 5.29 pH, and an oleoresin:wall material ratio of 1:2.5. Fourier Transform Infrared Spectroscopy (FT-IR) analysis of the coacervates before and after spray drying revealed the presence of the functional group C=N (associated with carbonyl groups of vanillin and amino groups of chitosan), indicating that microencapsulation by complex coacervation-spray drying was successful. The retention and encapsulation efficiencies were 84.89 ± 1.94% and 69.20 ± 1.79%. The microcapsules obtained from vanilla oleoresin had high vanillin concentration and the presence of other volatile compounds and essential fatty acids. All this improves the aroma and flavor of the product, increasing its consumption and application in various food matrices.

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Section: Resultssupporting

confidence: 81%

“…The band of the C–H groups was observed at 2926 cm −1 and corresponds to galactose, arabinose, and rhamnose found in CH, as well as in vanillin. This band indicated the C–H stretching vibrations of the methyl and methylene groups [ 50 ].…”

Section: Resultsmentioning

confidence: 99%

Microencapsulation of Vanilla Oleoresin (V. planifolia Andrews) by Complex Coacervation and Spray Drying: Physicochemical and Microstructural Characterization

Hernández-Fernández

García-Pinilla

Ocampo-Salinas

et al. 2020

Foods

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“…For the FT-IR spectra of the GA shown in Figure -(4-b), characteristic absorption bands were found at (1616 cm -1 ) as a broad peak and at (1420 cm -1 ) as narrower symmetrical peak, which can be attributed to the C-O-O bond stretching and carboxylic ion axial stretching, respectively. A broader absorption band is seen near 1030 cm -1 , which could be attributed to the bond (COH stretching) [29]. The broadband at 3410 cm -1 represents the characteristic peak of the -OH groups stretch of polysaccharide [7].…”

Section: Resultsmentioning

confidence: 96%

“…The broad absorption band at 3433 cm -1 indicates the existence of surface hydroxyl groups (O-H stretch)[7].For the FT-IR spectra of the GA shown in Figure-(4-b), characteristic absorption bands were found at (1616 cm -1 ) as a broad peak and at (1420 cm -1 ) as narrower symmetrical peak, which can be attributed to the C-O-O bond stretching and carboxylic ion axial stretching, respectively. A broader absorption band is seen near 1030 cm -1 , which could be attributed to the bond (COH stretching)[29]. The broadband at 3410 cm -1 represents the characteristic peak of the -OH groups stretch of polysaccharide[7].It was observed that, following coating with GA (Figure4-c), the characteristic absorption bands which appeared in (GA) spectrum (Figure4-b) were noticed in the spectrum of GA-magnetite NPs (Figure-4-c), confirming the fact that GA had successfully coated the surface of the synthesized magnetite NPs.…”

mentioning

confidence: 99%

Effects of Gum Arabic-Coated Magnetite Nanoparticles on the Removal of Pb Ions from Aqueous Solutions

Mustafa

Al‐Saadi

2021

eijs

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To study the removal of lead (Pb) ions from aqueous solutions, novel magnetite nanoparticles (NPs) of Ni0.31Mg0.15Ag0.04Fe2.5O4 were synthesized by coprecipitation synthesis using metal sulfates, and then coated with Gum Arabic (GA). The prepared NPs were analyzed using various spectroscopic and analytical methods, such as X-Ray diffraction analysis (XRD), Field Emission Scanning Electron Microscopy (FE-SEM), Energy Dispersive X-ray spectroscopy (EDX), Fourier Transform Infra-Red spectroscopy (FT-IR), and Atomic Absorption Spectrophotometer (AAS). By using XRD analysis, the cubic inverse spinel structure of the prepared NPs was proven, showing average values of crystallite size, lattice constant, and density of 28.57nm, 8.32582Å, and 5.2890 g/cm3, respectively. FE-SEM analysis revealed the sphere-like shape of the nanoparticles with a measured crystallite size of 25.93nm. The existence of constituent elements was evidenced by EDX. FT-IR test proved the success of the coating process of magnetite NPs by the presence of the main characteristic absorption bands of GA in the FT-IR spectrum of GA-magnetite NPs. The adsorption of Pb ions by GA- magnetite NPs was shown by AAS analysis, where the concentration of Pb ions decreased from 25ppm to 6.6ppm, reaching 1.1ppm at the time of 25min. The porosity of the NPs and the carboxyl groups in GA played an important role in the process.

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“…Para a remoção de tais metais, têm sido proposto bioadsorventes a base de polímeros naturais. O mecanismo de remoção por adsorção pode se constituir em um método mais atrativo, pois pode se apresentar como uma estratégia de menor custo, desde que se encontrem materiais adsorventes alternativos que sejam eficazes (ABREU et al,2018) A quitosana (QT) é o segundo biopolímero com a maior abundância através da desacetilação parcial da quitina que é derivada do exoesqueleto de crustáceos. (SHAH et al, 2016) É utilizada em diversas áreas, que vão desde a indústria alimentícia, farmacêutica, agroindústria e na área ambiental.…”

Section: Introductionunclassified