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.
Assessment of binary mixture toxicity of pharmaceuticals of environmental concern to aquatic organisms
2022 - BOIANI, N.F.; TOMINAGA, F.K.; SILVA, T.T.; REDÍGOLO, M.M.; BORRELY, S.I.
Pharmaceutical products have been frequently detected in aquatic environments as mixtures. They may cause direct toxic effects to aquatic organisms and indirect effects on ecosystems, due to interactions which induce additive, synergistic or antagonistic effects. The classical mathematical models of concentration addition and independent action of pollutants have been extensively used for predicting the mixture effects of chemicals of environmental relevance. The objective of this study was to assess the binary mixture toxicity of pharmaceuticals: fluoxetine and propranolol; fluoxetine and sulfadiazine; fluoxetine and caffeine, in acute tests with Daphnia similis carried out based on ABNT/NBR standard methods. The prediction of the acute effects to binary mixture was performed considering the mentioned mathematical models and deviations of them (synergism/antagonism; concentration level-dependent or concentration ratio-dependent), using an automated Excel spreadsheet. For the mixture of propranolol + fluoxetine, the concentration addition model best described the mixture effects, which explained most of the variability of acute toxic responses. Through the concentration level-dependent, synergism at low doses and antagonism at high doses was pointed out. The concentration addition model better described the effects of the binary mixture of sulfadiazine + fluoxetine. Synergism related to the independent action model and an antagonism related to the concentration ratio-depend were identified. For caffeine + fluoxetine mixture, the concentration addition model described slightly better the effects of this binary mixture, synergism concentration level-dependent and dose ratio-dependent were identified. We can conclude that the nature of the interaction between the compounds of a mixture depends on effect level and on the ratio in which each one is applied. Major effects of the binary mixture were detected in the zone between the effects predicted by the evaluated models. The synergism/antagonism or additivity do not depend on the similarity/dissimilarity of the mode of action of the compounds of a mixture, showing a different behaviour respect to the theoretical assumptions.
NAA and XRF techniques to investigate artistic paints
2022 - KOKA, A.C.S.S.; ZAMBONI, C.B.; GIOVANNI, D.N.S.; REDÍGOLO, M.M.
In this study, the multielemental characterization of artistic blue paints from the 90's and currently available ones in the Brazilian market was carried out using the Energy Dispersion X-Ray Fluorescence (EDXRF) and Neutron Activation Analysis techniques (NAA). These results aim to establish a reference database in the field. The EDXRF measurements was performed using portable X-ray spectrometer with Ag X-ray tube associated with a Si Drift detector (25 mm2 x 500 μm) with Be window (12.5 μm). The artistic paint samples were irradiated for 300 s using 30 kV and 5μA excitation. The quantitative analysis was performed using WinQXas software program (IAEA, version 1.3). The NAA measurements were performed in the nuclear reactor IEA-R1 (3.5- 4.5MW, pool type) at IPEN/CNEN-SP. Each sample was irradiated from minutes to hours and gamma counting was performed using HPGe detector (ORTEC-GEM 60195) coupled to an MCA (ORTEC - 919E). Concentration of all elements was obtained using the ATIVAÇÃO software. The results obtained by both techniques are in good agreement, in addition to being complementary. However, they do not correspond to the elemental content description provided by the manufacturer.
Analysis of XX century gold-silver coins by X-ray fluorescence and neutron tomography
2022 - ZAMBONI, C.B.; STANOJEV, M.; KOKA, A.C.S.S.; GIOVANNI, D.N.S.; REDÍGOLO, M.M.
X-ray fluorescence (XRF) is a technique capable of analyzing chemical elements on metallic surfaces, providing fast, sensitive, and reliable results while neutron tomography (NT) allows to investigate its internal structure by three-dimensional images. Both techniques are powerful tools for non-destructive analysis of artistic and historical objects. In this study, we explored the combined use of these techniques to investigate a set of Brazilian gold-silver coins dating from the early 20th century (1913-1938). This set of coins was select due to the lack of data related to their composition and origin. These data provide information to museologists for better cataloging / registration of fundamental information. Moreover, this information is vital for collectors and marchands in authentication processes. The X-Ray Fluorescence analysis was performed using X-Ray Spectrometer with gold (Au) and silver (Ag) targets. The excitation conditions were optimized in 30 kV and 5 μA and counting time of 200 s. A NT facility is installed at the beam-hole (BH-14) of the 4.5 MW pool-type IEA-R1 nuclear research reactor at IPEN (SP, Brazil). It consists of a 6LiF (ZnS) scintillator screen, a glass-based plane mirror, a video camera (16bit, 1024 x1024 pixels, cooled CCD) and a collimator to reduce the neutron beam size in the BH-14. The experimental conditions established were: 8 x106 ns-1 cm-2 (neutron flux), irradiation time/image of 1s, spatial resolution of 263 ± 35 μ and time tomography of 400s. The three-dimensional images were treated using dedicated software (OctopusV8.0 and VG studio Max2.2). The combined results bring information of elemental composition and 3D images highlight the conservation state of the pieces, being of great aid to conservators and museologists.
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.
Gas chromatography-mass spectrometry analysis of irradiated fluoxetine aqueous samples
2021 - REDÍGOLO, MARCELO M.; CALVO, WILSON A.P.; BOIANI, NATHALIA F.; TOMINAGA, FLAVIO K.; BORRELY, SUELI I.
The last decade witnessed the drastic increase in the use of antidepressant drugs, being fluoxetine the most prescribed worldwide. Conventional wastewater treatment is inefficient in removing fluoxetine and its accumulation in water bodies and water living organism is inevitable. Among several methods for contaminant removal from wastewater, electron beam irradiation is an efficient and green technology. This work presents the characterization of aqueous fluoxetine samples before and after irradiation. Gas chromatography coupled to mass spectrometry was used to identify the original compound and its irradiation products. Results indicate a drastic reduction in fluoxetine presence after the irradiation process. Radiolysis pathways were proposed based on mass fragments identification.
Degradation and toxicity of amoxicillin after electron beam irradiation
2021 - VILLARDI, B.D.; REDÍGOLO, M.M.; TOMINAGA, F.K.; LEBRE, D.T.; BORRELY, S.I.
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.