André R. Fajardo
Universidade Federal de Pelotas
Composite numberSelf-healing hydrogelsNuclear chemistryAdsorptionFourier transform infrared spectroscopyCatalysisDesorptionNanotechnologyAqueous solutionChemistryPolymer chemistryMaterials scienceSwellingCelluloseChondroitin sulfateChitosanDrug deliveryAcrylic acidVinyl alcoholChemical engineeringPolymer
81Publications
29H-index
2,685Citations
Publications 78
Newest
#2Cátia S. NunesH-Index: 6
Last. André R. Fajardo (UFPEL: Universidade Federal de Pelotas)H-Index: 29
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Abstract Hydrogels based on biopolymers like Gum Arabic (GA) usually show low applicability due to weak mechanical properties. To overcome this issue, (nano)fillers are utilized as reinforcing agents. Here, GA hydrogels were reinforced by chitin nanowhiskers (CtNWs, aspect ratio of 14) isolated from the biopolymer chitin through acid hydrolysis. Firstly, GA was chemically modified with glycidyl methacrylate (GMA), which allowed its crosslinking by free radical reactions. Next, hydrogel samples c...
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#1Thalia S.A. Lemos (UFPEL: Universidade Federal de Pelotas)
#2Jaqueline F. de Souza (UFPEL: Universidade Federal de Pelotas)H-Index: 4
Last. André R. Fajardo (UFPEL: Universidade Federal de Pelotas)H-Index: 29
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Abstract This study reports the preparation of microspheres of pectin and magnetite nanoparticles coated by chitosan to encapsulate and deliver drugs. Magnetic-pectin microspheres were obtained by ionotropic gelation followed by polyelectrolyte complexation with chitosan. Characterization data show that magnetite changes the physicochemical and morphological properties of the microspheres compared to the non-magnetic samples. Using metamizole (Mtz) as a drug model, the magnetic microspheres show...
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#1Guillermo Grazioli (University of the Republic)H-Index: 5
Last. Rafael R. MoraesH-Index: 34
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Novel poly(vinyl alcohol)/chondroitin sulfate (PVA/CS) composite hydrogels containing hydroxyapatite (HA) or Sr-doped HA (HASr) particles were synthesized by a freeze/thaw method and characterized aiming towards biomedical applications. HA and HASr were synthesized by a wet-precipitation method and added to the composite hydrogels in fractions up to 15 wt%. Physical-chemical characterizations of particles and hydrogels included scanning electron microscopy, energy-dispersive spectroscopy, Fourie...
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#1Jaqueline F. de Souza (UFPEL: Universidade Federal de Pelotas)H-Index: 4
#2Matheus S. Gularte (UFPEL: Universidade Federal de Pelotas)H-Index: 4
Last. André R. Fajardo (UFPEL: Universidade Federal de Pelotas)H-Index: 29
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Cu species (ions or nanoparticles) have gained considerable attention in many research fields, mainly in catalysis. In particular, the development of novel support materials, especially those based...
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#1Henrique P. Mota (UFPEL: Universidade Federal de Pelotas)H-Index: 2
#2André R. Fajardo (UFPEL: Universidade Federal de Pelotas)H-Index: 29
The growing consumption of anxiolytic drugs like diazepam (DZP) has aggravated the problem of persistent organic pollutants in water. Due to its characteristics, the removal of DZP from water and wastewater is a challenging task. As an effort to deals with this issue, in this study, we report the development of a hydrogel based on Gum Arabic (GA) grafted with poly(acrylic acid) (GA-g-PAAc) to be used in the adsorptive removal of DZP from water. The hydrogel formation was confirmed by Fourier-tra...
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Last. André R. Fajardo (UFPEL: Universidade Federal de Pelotas)H-Index: 29
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Abstract Dye-contamination in water supplies, industrial effluents, and rivers is one of the major water pollution issues. It has put at risk the drinking-water supplies around the globe. Various remediation approaches have been extensively developed and tested to minimize this worrying scenery. In particular, adsorption techniques are often ranked as one of the most prominent strategies to treat dye-contaminated water likely due to their attractive practical and economic advantages. Overall, th...
11 CitationsSource
#1Rafael F.N. Quadrado (UFPEL: Universidade Federal de Pelotas)H-Index: 7
#2André R. Fajardo (UFPEL: Universidade Federal de Pelotas)H-Index: 29
Abstract In this work, we have investigated the use of a heterogeneous catalyst based on reduced graphene oxide-grafted with carboxymethyl chitosan (rGO-CMCHT) and silver nanoparticles (AgNPs) for hydrogen generation through straightforward borohydride decomposition reaction. Thus, an rGO-CMCHT thin film containing AgNPs was successfully prepared by using a dip-coating technique. Characterization analysis indicated that rGO-CMCHT enhances the catalytic activity of AgNPs due to its intrinsic elec...
3 CitationsSource
#1Renata Bem dos Santos (Universidade Federal do Pampa)H-Index: 4
#2Kelly Ayumi Nakama (Universidade Federal do Pampa)H-Index: 3
Last. Sandra Elisa Haas (Universidade Federal do Pampa)H-Index: 9
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Abstract The present study aimed to develop nanocapsules (NCs) loaded with curcumin (CCM) using different coatings, comparing the effect of these coatings on physicochemical properties of NCs. NCs were prepared by interfacial deposition of performed polymer, using different polymers as coatings (P80, PEG, Chitosan and Eudragit RS100®) and then, characterized in detail by different techniques (AFM, FTIR, DSC, XRD, among others). In vitro studies were performed, evaluating the release profile, cyt...
1 CitationsSource
#1Antonio G.B. Pereira (UC Davis: University of California, Davis)H-Index: 25
#2André R. Fajardo (UFPEL: Universidade Federal de Pelotas)H-Index: 29
Last. You-Lo Hsieh (UC Davis: University of California, Davis)H-Index: 59
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Abstract Physical adsorption has shown to be facile and highly effective to deposit chitosan nanowhiskers (CsNWs, 60 % deacetylated, length: 247 nm, thickness: 4–12 nm, width:15 nm) on electrospun cellulose acetate nanofibers (CANFs, 560 nm) to effect complete surface charge reversal from negatively charged CANFs (−40 mV) to positively charged CsNWs-adsorbed CANFs (+8 mV). The CsNWs coverage did not alter the smooth and homogeneous morphology of fibers, as observed from SEM images. Biological as...
4 CitationsSource
#1Henrique P. Mota (UFPEL: Universidade Federal de Pelotas)H-Index: 2
#2Rafael F.N. Quadrado (UFPEL: Universidade Federal de Pelotas)H-Index: 7
Last. André R. Fajardo (UFPEL: Universidade Federal de Pelotas)H-Index: 29
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Abstract Herein, Zn(II)-porphyrin/poly(acrylic acid) (Zn(II)Pr@PAA) hybrid microparticles were synthesized to act as catalyst for the photodegradation of the aqueous organic pollutants under artificial visible light or natural sunlight. The microparticles were characterized by different analytical and microscopic techniques, which showed that the immobilized metalloporphyrin affects the final properties of the hybrid microparticles. Moreover, photodegradation experiments revealed that the Zn(II)...
17 CitationsSource