MARCELO MIYADA REDÍGOLO

MARCELO MIYADA REDÍGOLO

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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.
Micro- and nanoplastics in the sediments of the Santos Estuarine System, Brazil
2018 - GIMILIANI, G.T.; REDÍGOLO, M.M.; FORNARI, M.; PARRA, D.F.; LUGAO, A.B.; ABESSA, D.M.S.; COTRIM, M.E.B.; PIRES, M.A.F.
Small-scale plastic debris, such as microplastics and nanoplastics has become leading contributors to the pollution of marine and freshwater ecosystems [1]. These particles are derived from plastic degradation and produced intentionally for manufacturing products [2]. Microplastics are fragments and fibers smaller than 5 mm [3], while the definition of nanoplastics is still under debate; different studies have set the upper size limit at either 1000 nm or 100 nm [2]. The changes in the density of floating plastic debris caused by weathering process, biofilm formation and biofouling may result in sedimentation of these particles [3]. The present study investigates the presence of the micro- and nanoplastics in marine and estuarine sediments because these environments are suggested to be long-term sinks for microplastics. This study is the first investigative analysis about the presence of the micro- and nanoplastics on sediments of the Santos Estuarine System (SES), central coast of the São Paulo State, southeastern Brazil. Sediment samples from four sites distributed along in the Bugres River (23º56’49’’S – 46º22’57’’W), a small estuarine inlet located within the SES, were collected using a Van Veen grab sampler. In laboratory, the samples were then sieved with different mesh sizes (including < 63 μm), dried and evaluated for type of polymer by infrared spectroscopy (IR) and quantification of microplastics by visual sorting. IR analyses indicated that polyethylene and polypropylene were the main types of polymers found in fragments. Abundance of microplastics were likely inversely related to the mesh size of the sieve. Thus, the amount of microplastics increases as the size fractions decreases. Values ranged from 19 to 4,700 particles g-1 of sediment for 2 mm, 450 to 1,900.00 particles g-1 for 1 mm, 634 to 7,440 particles g-1 for 500 μm, 447 to 26,520 particles g-1 for 250 μm. The concentration of fibers ranged from 1.24 to 14.75 times higher compared to the concentration of fragments. In addition, the abundance of microplastics for 125, 63 and < 63 μm will be analyzed by thermogravimetric technique. Considering that the largest abundances of microplastics were found in the smallest meshes, it is expected the presence of nanoplastics in the sediment samples. The results of this study revealed relatively high concentrations of microplastics in sediments of the SES, confirming the widespread occurrence of microplastics in the Bugres River.
Caracterização química multitécnicas de tintas artísticas brasileiras, um estudo de caso
2018 - REDIGOLO, MARCELO M.
O presente trabalho apresenta a caracterização química de tintas artísticas brasileiras. Diferente de outras matrizes, os materiais de arte fabricados no Brasil não apresentam informações na literatura que auxiliem em sua conservação e restauração. Amostras de tintas acrílicas e a óleo, nacionais e importadas, foram analisadas pelas técnicas espectroscópicas Raman e infravermelho por transformada de Fourier (FTIR), pirólise acoplada a cromatografia a gás e espectrometria de massas (Py-GC/MS) e microscopia eletrônica de varredura acoplada a espectrometria de fluorescência de raios X (SEM-EDS). Resultados de análise indicam que tintas acrílicas brasileiras são compostas por poliestireno (PS), diferentemente das importadas, compostas por polimetilmetacrilato (PMMA). Enquanto as tintas a óleo apresentam composição semelhante (óleo de linhaça), brasileiras e importadas. Duas pinturas do acervo da Pinacoteca do Estado de São Paulo foram selecionadas para um estudo de caso. As obras apresentam a formação de exsudatos em sua superfície, o que demanda a caracterização química como etapa anterior ao desenvolvimento de uma metodologia de restauração. A obra "Mandala da saudade", de Sara Goldman-Belz, é composta por tinta spray (alkyd) e a obra "Três pessoas", de Marina Saleme, por tinta a óleo. Os resultados de análise apresentam um primeiro passo no estabelecimento de um banco de dados de materiais artísticos fabricados no Brasil para fins de restauração e perícia criminal de obras de arte.
Preparación de muestras del médio ambiente para análisis por médio de técnicas cromatograficas
2017 - VEGA, O.; LOPES, P.R.; AMARAL, P.O.; GONSCHOROWSKI, G.; OLIVEIRA, J.P.; FABBRO, R.; MESQUITA, K.A.; GIMENEZ, M.P.; REDIGOLO, M.
Este artículo explora la ciencia de la preparación de muestras para matrices sólidas, líquidos y gases, utilizados en el laboratorio del Centro de Química y Medio Ambiente del IPEN. Extracción de neonicotinoides del agua por LLE (Liquid-Liquid Extraction), extracción de hidrocarburos aromáticos policíclicos (PAHs) del agua atraves de DLLME (Dispersive liquid - liquid micro extraction) y el uso de extracción en fase sólida SPE (Solid Phase Extraction) para el análisis de hormonas en agua son descritos. Limites de detección que utilizan estas técnicas son descritas en este trabajo.
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.
Chemical characterization of persistent organic pollutants (POPs) and development of its decomposition in an industrial area of São Paulo, Brazil
2015 - OLIVEIRA, J.P.R.; RIELLA, H.G.; LAINETTI, P.; REDIGOLO, M.M.; AMARAL, P.O.; MOURA, S.C.; BUSTILLOS, J.O.V.
PY-GC-MS applied to the identification of synthetic resins in brazilian painting
2015 - REDIGOLO, MARCELO M.; AMARAL, PRISCILA O.; LEAO, CLAUDIO; CREPALDI, CAIKE; RUSSO, TATIANA; MENDONCA, VALERIA de; MUNITA, CASIMIRO S.; BUSTILLOS, OSCAR V.
Analysis of hydrogen, carbon, sulfur and volatile compounds in (Usub(3)Sisub(2)-Al) nuclear fuel
2015 - MOURA, SERGIO C.; REDIGOLO, MARCELO M.; AMARAL, PRISCILA O.; LEAO, CLAUDIO; OLIVEIRA, GLAUCIA A.C. de; BUSTILLOS, OSCAR V.
Development of method for determination of sodium monochloroacetate and sodium dichloroacetate in cocoamido propyl betaine by gas chromatography: FID, ECD and MS
2015 - LEAO, CLAUDIO; REDIGOLO, MARCELO M.; AMARAL, PRISCILA O.; BUSTILLOS, OSCAR V.
Analysis of neonicotinoids by gas chromatography coupled to nuclide sup(63)Ni - electron capture detector - GC/ECD
2015 - AMARAL, PRISCILA O.; LEAO, CLAUDIO; REDIGOLO, MARCELO M.; CREPALDI, CAIKE; BUSTILLOS, OSCAR V.