MARCELO MIYADA REDÍGOLO

MARCELO MIYADA REDÍGOLO

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Ecotoxicological assessment of metformin as an antidiabetic water residue treated by electron beam accelerator irradiation
2024 - TOMINAGA, FLAVIO K.; JESUS, JULIANA M.S. de; KLANOVICZ, NATALIA; REDIGOLO, MARCELO M.; SILVA, THALITA T.; LEBRE, DANIEL T.; TEIXEIRA, ANTONIO C.S.C.; LEO, PATRICIA; BORRELY, SUELI I.
Metformin (MET), an antidiabetic compound, has received increasing attention, as it cannot be effectively removed during conventional wastewater treatment processes and may act as an endocrine disruptor. Electron beam irradiation (EBI) is an eco-friendly process able to degrade and neutralize biohazardous pollution almost instantly. In this context, this study applied EBI to MET degradation and detoxification in aqueous solutions. A 98% MET degradation rate and TOC removal of 19.04 ± 1.20% at a 1.0 kGy EBI dose was obtained, with up to 65% mineralization reached at 5.0 kGy. Toxicity assays were performed with Vibrio fischeri, Saccharomyces cerevisiae, and Daphnia similis, and the findings indicate that generated byproducts were only more toxic to D. similis. This reveals the need to assess organisms belonging to different trophic levels. A cytotoxic assessment employing Allium cepa roots demonstrated no toxic effects concerning untreated and irradiated samples.
Toxicity removal of pharmaceuticals, fluoxetine and caffeine, by electron beam irradiation
2023 - BOIANI, NATHALIA F.; REDIGOLO, MARCELO M.; CALVO, WILSON A.; TOMINAGA, FLAVIO K.; BORRELY, SUELI I.
The wide use of pharmaceuticals and water scarcity are associated to increasing levels of pharmaceutical compounds discharged into water and wastewater worldwide, affecting relevant ecological services, including biodegradation. However, water pollution has also encouraged studies applying advanced oxidative processes (AOP) in organic pollutant degradation. Among AOPs, ionizing radiation has been proven an effective technology for organic compound removal from waters and wastewater. The objective of this study was to assess Electron Beam (EB) irradiation in the degradation of caffeine and fluoxetine and their binary mixture in pure aqueous solutions. The degradation of these pharmaceuticals was evaluated by GC/MS analyses. The degradation dose response was higher for the caffeine and fluoxetine mixture (1:1) at 2.5 kGy. This dose led to decreased toxicity towards Daphnia similis for both the fluoxetine + caffeine mixture and the isolated fluoxetine solution, but not for the isolated caffeine. On the other hand, Vibrio fischeri exposure for 15 min indicated toxicity removal for the entire pharmaceuticals sample set and radiation dose. Fluoxetine was the most toxic pharmaceutical, followed by the binary mixture. Thus, we suggest ecopharmacovigilance, where attention should be paid to the increasing amount of pharmaceuticals, caffeine and fluoxetine detected in water.
Degradation and toxicity of amoxicillin after electron beam irradiation
2022 - BORRELY, S.I.; REDÍGOLO, M.M.; VILLARD, B.D.; LEBRE, D.T.; TOMINAGA, F.K.
A recent and growing concern in environmental studies is the presence of antibiotics in wastewater, which contributes to antimicrobial resistance building. Amoxicillin, according to the World Health Organization, is one of the most consumed antibiotics worldwide, for being a first line therapy for common infections. Among several drug degradation methodologies, electron beam irradiation (EBI) is presented as an efficient and green treatment. This work presents data on amoxicillin degradation via EBI. Degradation rate was evaluated by LC/MS-MS, carbon removal efficiency was evaluated by TOC and ecotoxicity assays were performed employing Vibrio fischeri. Chromatographic results indicate an efficiency removal of 97.65% at 0.75 kGy and concentration below the limit of detection with increasing absorbed dose. Low mineralization (up to 10%) was achieved at 3.0 kGy. Regarding toxicity, approximately 81% of toxicity removal was obtained at 0.75 kGy and a decrease in efficiency was achieved with higher doses. In conclusion, results indicate the low doses (0.75 kGy) as most effective for drug removal employing EBI.
Non-destructive analysis in the study of historical photographs by pXRF and ATR-FTIR spectroscopies
2021 - ZAMBONI, CIBELE B.; REDÍGOLO, MARCELO M.; MIURA, VINICIUS T.; COSTA, ISOLDA; NAGAI, MARIA L.E.; SALVADOR, PABLO A.V.; SILVA, DALTON G.N. da
Material characterization is essential to the provenance of graphic arts. Non-destructive analytical techniques are increasingly required in the authentication process of cultural heritage. This work presents a suite of portable, non-destructive, and complementary analytical techniques, energy dispersive x-ray fluorescence (EDXRF), Fourier transform infrared (FTIR) spectroscopies, and brightfield microscopy, applied to the analysis of historical photographs depicting São Paulo city architecture, whose registration date and process of fabrication are unknown. The EDXRF analysis emphasizes the use of typical POP (printing-out paper) photograph with baryta (BaSO4) coated paper substrate while the FTIR and microscopy analyses confirm the presence of collodion and a gelatin-based baryta layer. This photographic process was widely employed by professional photographers from 1889 to 1930, when it was gradually abandoned in commercial use. This time interval (1889–1930) is consistent with the information surveyed on the photographic collection. In conclusion, employing complementary techniques (elemental and molecular spectroscopies and image magnification) is essential in identifying the manufacturing materials of cultural heritage material, which is the basis of contemporary authentication procedures. These data provide to curators and historians fundamental information for cataloging, adding subsidies for the correct storage and preservation (“heritage appreciation”). Still, for professional photographers, they present information on the manufacturing processes of historical photographs. The data from the present study also emphasize its perspective of use in graphic arts to aid connoisseurship in identifying forgeries during provenance and authentication studies.
Simple and cost-effective method for microplastic quantification in estuarine sediment
2020 - GIMILIANI, GIOVANA T.; FORNARI, MILENE; REDÍGOLO, MARCELO M.; BUSTILLOS, JOSE O.W.V.; ABESSA, DENIS M. de S.; PIRES, MARIA A.F.
Sediment is a useful environmental compartment in the evaluation and monitoring of microplastics (i.e., plastic particles between 1 μm and 5 mm in length) in aquatic environments, since 70% of plastic waste is deposited on the ocean floor, in riverbeds, and on the bottom of estuaries. The techniques typically used to separate and quantify microplastics require extensive sample preparation and are often ineffective for estuarine sediment samples. In this study, we present a new method for separating and quantifying microplastics found in estuarine sediment samples. This procedure involves sediment collection, drying, sieving (2.0, 1.0, 0.5 and 0.25 mm mesh sizes), and stereomicroscopic examination of the samples retained in each sieve. The results were measured as microplastic abundance (particles g-1 of sediment). This method allows researchers to estimate total microplastic abundance and distribution at the sieve meshes tested, calculate thread/fiber and fragment proportions, and separate microplastic samples for subsequent Py-GC/MS analysis in order to identify their respective compositions. This method was found to be effective in precluding the need for solvents and reducing the amount of time required for sample preparation. For these reasons, this method is more cost-effective and generates less environmental impact than those currently available.
Material characterization of exudates from Brazilian contemporary oil painting by FTIR, Py-GC/MS and SEM-EDS
2020 - REDÍGOLO, M.M.; ALVES, M.V.R.; REIS, T.R. dos; CARNEIRO, T.C.; COSTA, I.; BUSTILLOS, O.V.
Contemporary art has employed almost every single synthetic material created by man. Nonetheless, the appeal of oil paint is still present at most public and private collections. Oil paint manufacture has evolved over time along with its formulation and conservation concerns. A reported problem is the formation of exudates on contemporary oil paintings. This work aims to characterize exudates from the Brazilian oil painting “Três pessoas” (1999), by Marina Saleme. Characterization was carried out by Fourier transform infrared spectroscopy, pyrolysis coupled to gas chromatography and mass spectrometry and scanning electron microscopy coupled to energy dispersive x-ray fluorescence spectrometry. Results indicate that exudates are formed by the oxidation of linseed oil and formation of dicarboxylic acids. This process is aided by the formation of zinc stearate in the paint film.
The effect of acid pickling on the corrosion behavior of a cerium conversion-coated AA2198-T851 Al-Cu-Li alloy
2020 - KLUMPP, RAFAEL E.; DONATUS, UYIME; ARAUJO, JOAO V.S.; REDÍGOLO, MARCELO M.; MACHADO, CARULINE de S.C.; COSTA, ISOLDA
The effect of acid pickling pretreatments prior to cerium conversion coating process on the corrosion behavior of AA2198-T851 alloy substrates was investigated. Three acid pretreatments were employed: nitric acid (HNO3), phosphoric acid (H3PO4) and sulfuric acid (H2SO4). The cerium conversion coating process was performed using a batch solution composed of cerium nitrate and hydrogen peroxide. Microscopic techniques, electrochemical impedance spectroscopy, polarization resistance and open-circuit potential measurements were employed to investigate the effect of each acid pretreatment. The untreated and nitric acid pretreated substrates presented more defective cerium conversion layers than the substrates treated with phosphoric and sulfuric acids. Accordingly, the corrosion resistance of the untreated and nitric acid-treated substrates was very low, while that of the substrates treated with phosphoric acid and sulfuric acids were greatly improved. The sulfuric acid pickling treatment was the best pretreatment before cerium conversion coating among the investigated pretreatments on the AA2198-T851 Al-Cu-Li alloy.
A multi-analytical study of Brazilian commercial acrylic paint of artistic use
2019 - REDÍGOLO, MARCELO M.; ALVES, MARCOS V.R.; COSTA, ISOLDA; BUSTILLOS, OSCAR V.
Contemporary Brazilian artists worked massively with paints made in Brazil. Conservation of acrylic paints is an issue and has been studied for the past two decades. European and North American paints were studied in detail, but there is scarce information on paints produced in other countries. Therefore, it is vital to characterize Brazilian artist paint and better understand their ageing process, outlining proper conservation methodologies then. Complementary analytical techniques were employed to characterize the paint samples, namely pyrolysis gas chromatography-mass spectrometry (Py-GC/MS), Fourier transform infrared (FTIR) and Raman spectroscopies and scanning electron microscopy-energy dispersive X-ray spectroscopy (SEM-EDS). Results indicate that Brazilian acrylic blue paints (phthalocyanine and Prussian) are composed of polystyrene (PS) copolymers, in contrast to imported paints, mainly composed of poly(metyhl methacrylate) (PMMA) copolymers.
Comparative study of inorganic elements determined in whole blood from Dmdsup(mdx)/J mice strain by EDXRF and NAA analytical techniques
2016 - REDIGOLO, M.M.; SATO, I.M.; METAIRON, S.; ZAMBONI, C.B.
Comparative study of inorganic elements determination in whole blood from Crioula breed horse by EDXRF and NAA analytical techniques
2012 - BAPTISTA, TATYANA S.; REDIGOLO, MARCELO M.; ZAMBONI, CIBELE B.; SATO, IVONE M.; MARCELINO, JOSE R.