LUIS GUILHERME MASSAKI LEAL

LUIS GUILHERME MASSAKI LEAL

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Characterization of the Scaptotrigona aff. Postica bee from Brazil using analytical techniques
2019 - LEAL, LUIS G.M.; ZAMBONI, CIBELE B.; NASCIMENTO, ROBERTO M. do; MENDONÇA, RONALDO Z.; SIMONS, SIMONE M.
The study aimed to propose the characterization of the Scaptotrigona aff. Postica Bee (“tubi”) from Barra do Corda (MA-Brazil). This species produces honey, propolis and pollen with several medical applications. Two analytic techniques were applied for this investigation: Instrumental Neutron Activation Analysis (INAA) and Energy Dispersive X Ray Fluorescence (EDXFR). The elements Br, Ca, Cl, Co, Cu, Fe, K, Mn, Na and S were identified in all samples. The results obtained from INAA were compared with EDXRF technique and they are in good agreement. Both analytical techniques proved to be adequate and complementary, offering a new contribution to the understanding of the relation of these bees to the vegetation that surrounds the meliponary.
Characterization of the extract of propolis produced by Scaptotrigona aff. Postiça bee from Brazil using NAA and XRF techniques
2018 - LEAL, LUIS G.M.; ZAMBONI, C.B.; MENDONÇA, RONALDO Z.; SIMONS, SIMONE M.; NASCIMENTO, ROBERTO M. do
The objective of this investigation was to perform a multielemental characterization of the extract of the propolis produced by Scaptotrigona a® Posti»ca Bee (\tubi") from Barra do Corda (MA-Brasil). The extract produced by this propolis have several medical applications: it is used in the healing of wounds with an in°ammatory process, in treatment of prostate tumors and, it has activity against herpes and rubella virus [1-3]. Two analytic techniques were applied for investigation: Neutron Activation Analysis (NAA) and X Ray Fluorescence (XRF). The neutron activation measurements were performed using the IEA-R1 nuclear reactor at IPEN - CNEN/SP and XRF data were obtained using a compact X- Ray spectrometer (X-123 SDD, Amptek) constituted by a Silicon detector coupled a mini X-ray tube (Ag). Direct analysis using EDXRF was compared with INAA procedure to evaluate the e®ect matrix and the results were satisfactory. These data increase the knowledge of the components and can introduce improvements in the production these extracts, mainly as regards to toxicity and nutritional composition.
Elemental caracterization of the extract of propolis produced by Scaptotrigona Aff postica bee from Brazil using EDXRF and INAA techniques
2018 - LEAL, L.G.M.; ZAMBONI, C.B.; GIOVANNI, D.N.S.; NASCINTO, R.M.; MENDONCA, R.Z.; SIMONS, M.S.
The Scaptotrigona Aff Postica bee is an insect stingless belonging to Apidae family and subfamily Meliponinae. This genus occurs throughout in Neotropics. In Brazil, it is found in the northeastern mainly in the Barra do Corda County (Maranhão). Specifically, the extract of propolis produced by this bee have several medical applications. It is used in the healing of wounds with an inflammatory process and in treatment of prostate tumors as well as food supplement [1-3]. Considering its importance in medicinal use and the great variability in relation to botanical origin, its standardization in relation to the dosage of ions and metal is important to meet the different medical applications. The objective of this investigation was to perform a multielemental characterization using Energy Dispersive X-Ray Fluorescence (EDXRF) and Instrumental Neutron Activation Analysis (INAA) techniques. The neutron activation measurement was performed in the nuclear reactor (IEA-R1, 3-4 MW, at IPEN) and XRF data were obtained using a mini - X Ray spectrometer with Ag and Au targets. These data increase the knowledge of its inorganic components and can introduce improvements in the production these the extracts, mainly as regards to toxicity. Moreover, considering that the demand for natural products has increase (Brazil stands out as world exporter of honey and derivatives), these data also contributes for checking the quality and food safety.
Elemental characterization of the extract of propolis produced by scaptotrigona postiça bee from Brazil using NAA
2017 - LEAL, L.G.M.; ZAMBONI, C.B.; SILVA, D.G.N.; MEDEIROS, J.A.G.; SIMONS, S.M.; MENDONCA, R.Z.; NASCINTO, R.M.
The Scaptotrigona postiça bee is a stingless insect belonging to Apidae family and subfamily Meliponinae. This genus occurs throughout in Neotropics. In Brazil, it is found in the northeastern mainly in the Barra do Corda County (Maranhão). Specifically, the propolis produced by this bee have several medical applications: it is used in the healing of wounds with an inflammatory process and in treatment of prostate tumors. Considering its importance in medicinal use and the great variability in relation to botanical origin, its standardization in relation to the dosage of inorganic elements is important to meet the different medical applications. The objective of this investigation was to perform a multielemental characterization using Neutron Activation Analysis technique. The measurements were performed using the IEA-R1 nuclear reactor at IPEN – CNEN/SP (Brasil). These data increase the knowledge of its inorganic components and can introduce improvements in the production of these extracts, mainly as regards to toxicity.
Quantitative analysis of light elements using compact XRF spectrometers
2017 - ZAMBONI, CIBELE B.; SILVA, DALTON G.N. da; MORGADO, RAFAEL S.; ZANATA, THIAGO; LEAL, LUIS G.M.; MOREIRA, DAVISON de M.
The use of analytical techniques to investigate specific ions in body fluids has increase in last year’s presenting significant progress in clinical tests. This motivated us to check the performance of two compacts XRF spectrometers (X-123SDD, Amptek) consisting of Ag and Au X-ray mini-tubes associated with a Si Drift detector (25 mm2 x 500 μm) with Be window (12.5 μm) for this clinical finality. Using the Energy Dispersive X-Ray Fluorescence technique (EDXRF) specific ions of clinical relevance, such as, Ca, Cl, Fe and K were investigated using standards (certified solutions). A simplified sample preparation procedure was proposed, i.e., the liquid samples were dripped in filter paper (Whatman, n° 41) and dried for a few seconds using infrared lamp and dry for few seconds using infrared lamp. The performance of these spectrometers were checked by evaluation of several parameter (linearity, reproducibility, accuracy, precision, sensitivity and detection limit) usually considered for validation procedures on analytical methods, in according to ISO 17025 and EURACHEM/CITAC norms. For simultaneous determination of these ions, the optimized excitation condition was established by 300s using 5μA and 30kV. The method was proved to give reliable results with limits of detection at levels of 0.23 to 0.58 mgL−1 for. Considering that the ranges of the body fluids, such as: blood, saliva, serum and urine, are in the order of hundreds of mg L-1, this procedure is very promising for ions dosage requiring a small amount of sample (50μL, 10 times less comparatively to the conventional tests), simultaneous analysis, short time of analysis (minutes) and simple sample preparation. In addition, this procedure offers a non-destructive alternative for clinical usage. Finally, these compact spectrometers have potential use when the biological material is scarce, case of the pediatric practice in newborns and premature infants (blood collection is the main cause of transfusions) and in vivo tests, in small size animal model (mice and rats), in order to evaluate the safety of new drugs, vaccines and others medical supplies.