NATANAEL GOMES DA SILVA

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  • Artigo IPEN-doc 26245
    Proposal of an identification test for MIBI-TEC® lyophilized reagent using infrared spectroscopy
    2019 - SANTOS, JOEL M. dos; FUKUMORI, NEUZA T.O.; OLIVEIRA, IDELI M. de; MARTINS, PATRICIA de A.; SILVA, NATANAEL G. da; MATSUDA, MARGARETH M.N.
    Quality Control is part of the Good Manufacturing Practices (GMP) responsible for the evaluation and release of pharmaceutical components, including active ingredients and excipients, to assure compliance with the specifications in pharmacopoeias. GMP for radiopharmaceuticals is regulated by RDC N. 17/2010 and RDC N. 63/2009 (ANVISA) establishing the minimum quality standards in industrial manufacture. Pharmacopoeias have the specifications for lyophilized reagents (LR) labeled with 99mTc regarding radiochemical purity, biodistribution and, in case of parenteral use, bacterial endotoxins and sterility tests must be performed. In radiopharmaceutical monographs, the necessity of non radioactivity assays for releasing lyophilized reagents are not well described, but ANVISA requires assays to assure the quality of the lyophilized powder, as active ingredient quantification and identification assays, stannous ion quantification and moisture determination. Infrared (IR) spectroscopy is widely used for identification of substances, mainly raw materials. The aim of this work is to propose an identification assay for MIBI-TEC® LR powder using IR spectroscopy. MIBI-TEC® batches were produced at IPEN/CNEN-SP and about 2 mg of the LR powder were mixed with 200 mg KBr, pressed at 80 kgf during 5 minutes into the holder to obtain a transparent pellet. The pellet was placed in ABB IR spectrometer, FTLA 2000 model, and a spectrum in the medium infrared region of 450 to 4000 cm-1 was acquired using Grams software. Tetramibi cuprous tetrafluoroborate, stannous chloride dihydrate, cysteine hydrochloride monohydrate, sodium citrate and mannitol had their respective IR spectrum recorded and the main characteristic absorptions were established for each formulation component. In the MIBI-TEC® spectrum, it was possible to observe a well characterized absorption in 2193 cm-1 which represents the presence of C≡N binding of tetramibi cuprous tetrafluoroborate active ingredient, free of interference, indicating that IR spectrum can be used as identification assay of the LR.
  • Artigo IPEN-doc 26239
    Dose calibrator and gamma counter
    2019 - SILVA, VITOR M.A. da; SOUSA, JURANDIR A. de; MARTINS, PATRICIA de A.; FUKUMORI, NEUZA T.O.; SILVA, NATANAEL G. da; MATSUDA, MARGARETH M.N.
    To ensure that pharmaceutical products have and maintain the structure, identity, purity, concentration, potency and safety characteristics required for their use, there is a set of standard procedures called Good Manufacturing Practices (GMP). In Brazil, the National Sanitary Surveillance Agency (ANVISA) regulates the GMP production of medicines through RDC17/2010 and for radiopharmaceuticals through RDC 63/2009 and 38/2008, to ensure their safe and correct use in commercial production and nuclear medicine services, respectively. Most 99mTc radiopharmaceutical monographs have biological distribution specifications. Using invasive method, 99mTcradiopharmaceuticalsare assessed by the injection into animals of defined strains and the radioactivity (as percentage of retainedor injected dose -%RDor%ID)ismeasured in specified organs. Technetium-99m Sestamibi radiopharmaceutical (99mTc-2-methoxy-isobutyl-isonitrile; 99mTc-sestamibi; MIBI-TEC®) monograph is related in USP 41, but the biological distribution assay is not included. At IPEN, the biodistribution test is performed as established in the Radiopharmaceutical Quality Control Manual of ARCAL XV (1999) - International Atomic Energy Agency (IAEA), for each batch. The objective of this work is to compare MIBI-TEC®biodistribution results using dose calibrator and gamma counter with sodium iodide detector by measuring the radioactivity in the organs. Three batches of MIBI-TEC®were used and 1 vial of lyophilized reagent (LR) was labeled with 5-10 mCiin 1-3 mL of 99mTc eluate. 200-300 μCi in 0.2 mLwereinjected in 3 Balb-Cmice. After 30 minutes of biodistribution, heart, lung, muscle, liver, paw, column and tail were withdrawn, weighed and radioactivity was measured in dose calibrator and gamma counter (μCi andcpm, respectively). %ID/g ratio in the organs of interest was calculated using the data obtained by both equipment and the results were compared. No significant differences were observed and it was possible to conclude that either a dose calibrator or a gamma counter can be used in the routine of quality control.
  • Dissertação IPEN-doc 25658
    Estudo das formulações e controle de qualidade in vitro e in vivo de MAG3-99mTc para aplicação renal em medicina nuclear
    2017 - SILVA, NATANAEL G. da
    Os radiofármacos são preparações farmacêuticas com finalidade diagnóstica ou terapêutica que, quando prontas para o uso, contêm um ou mais radionuclídeos. São utilizados em Medicina Nuclear para diagnóstico e terapia de várias doenças. O tecnécio-99m-mercaptoacetiltriglicina (MAG3-99mTc) foi primeiramente preparado em 1986 na Universidade de Utah pelo Dr. Alan R. Fritzberg e tem sido utilizado para avaliação da filtração glomerular e dos túbulos renais. O objetivo deste trabalho foi definir as condições de preparação de uma formulação para obtenção de MAG3 na forma de um reagente liofilizado comercial, para ser marcado com 99mTc. Inicialmente foram preparados lotes teste baseados nas formulações europeia e americana, com pH final 6 e os resultados foram insatisfatórios. A mudança de pH para 12 resultou em aumento na pureza radioquímica, porém sem estabilidade de marcação com 99mTc em até 4 horas. O teste com a formulação cubana em pH 9,5 resultou em pureza radioquímica (% PRq) maior que 90% até 4 horas de marcação. O limite especificado para % PRq é de 90%. Com base nos resultados anteriores, foram definidos os componentes da formulação IPEN e três lotes do produto liofilizado com 100 frascos cada, foram avaliados quanto à estabilidade radioquímica e biológica até cerca de 9 meses. Quatro lotes piloto produzidos com 230 frascos liofilizados cada, estão em estudo de estabilidade até o presente momento. As atividades de marcação com 99mTc foram 0,74 - 3700 MBq (5 - 100 mCi), em 3 mL de NaCl 0,9%. A % PRq foi determinada em até 240 minutos de marcação utilizando cromatografia em camada delgada, com 2 sistemas diferentes: Metiletilcetona:acetato de etila 60:40 (v/v) em fita de iTLC-SG para determinação de 99mTcO4- em Rf = 1 e Acetonitrila:água 50:50 (v/v) em fita Whatman 3MM para determinação de 99mTcO2 em Rf = 0. Os resultados foram expressos como média % PRq ± desvio padrão considerando-se análises em duplicata de dois frascos para cada um dos tempos de marcação. 0,74 MBq (200 μCi) de atividade mínima ou 129,5 MBq (3500 μCi) de atividade máxima de marcação em 0,1 mL NaCl 0.9% foram administrados em camundongos Swiss e a radioatividade nos rins, fígado e vesícula, estômago, intestino e carcaça foi medida após 45 minutos. Os valores foram expressos como média % DI (Dose Injetada) ± DP. O estudo de toxicidade aguda foi realizado em um grupo de 10 camundongos machos da linhagem Balb/c, pesando entre 20-30 g, com cerca de dois meses de vida, por um período de 14 dias. Todos os resultados de controle de qualidade atenderam aos critérios especificados. Observou-se que o preparo e a adição dos reagentes, a quantidade de cloreto estanoso e o valor de pH nas etapas intermediárias foram fatores importantes na obtenção de um radiofármaco para marcação com 99mTc, como no caso do MAG3.
  • Artigo IPEN-doc 24106
    Study of 99mTc-DMSA biodistribution in experimental animals
    2017 - CASTRO, THAIS O.M. de; SILVA, NATANAEL G. da; COLTURATO, MARIA T.; FELGUEIRAS, CARLOS F.; MENGATTI, JAIR; FUKUMORI, NEUZA T.O.; MATSUDA, MARGARETH M.N.; ARAUJO, ELAINE B. de
    99mTc-DMSA, succimer (99m Tc), is a radiopharmaceutical commonly used in nuclear medicine for renal function evaluation by imaging. In order to achieve adequate labeling of the product with good radiochemical yield and standardized biological distribution, the interval of 185 - 3700 MBq should be kept in a maximum volume of 3 mL for product labeling. Moreover, one should avoid exposing the reconstituted solution to oxygen and using the product after four hours post labeling. The aim of the study was to quantify and evaluate the influence of different DMSA complexes on biological distribution of the radiopharmaceutical in experimental animals, taking in account variations in the labeling parameters. Radiochemical purity was determined by paper and thin layer chromatography using both acetone/Whatman 3MM, 0.9% NaCl/TLC-SG and npropanol/ H2O/acetic acid (4:3:1 V/V/V)/TLC-SG systems respectively for quantification of 99mTcO4 - and 99mTcO2 plus some 99mTc-DMSA complexes. The labeling activity did not significantly affect the extent of the main complex generation. The presence of oxygen and the concentration of 99Tc did not markedly change the percentage of the radiochemical impurities in the preparation. Radiochemical purity tests of the DMSA-99mTc based on IPEN-CNEN DMSA-TEC reagent and on another producer’s reagent showed similar results. Although the routine method used by IPEN-CNEN to determine the radiochemical yield of 99mTc-DMSA was not able to discriminate among 99mTc-DMSA complexes, the renal uptake and the kidney to liver plus spleen uptake ratio in rats met the official compendia criteria for the radiopharmaceutical.
  • Artigo IPEN-doc 15768
    Metodo cintilografico nao invasivo para estudo de biodistribuicao de radiofarmacos
    2010 - ALMEIDA, ERIKA V.; SILVA, NATANAEL G.; FREIRE, ANTONIO C.; MONTEIRO, ELISIANE de G.; BENEDETTI, STELLA; MURAMOTO, EMIKO; FUKUMORI, NEUZA T.O.; MATSUDA, MARGARETH M.N.; VASCONCELLOS, MARINA B.A.
  • Artigo IPEN-doc 19394
    Acute and subacute toxicity of sup(18)F-FDG
    2013 - DANTAS, DANIELLE M.; SILVA, NATANAEL G. da; MANETTA, ANA P.; OSSO JUNIOR, JOAO A.
  • Artigo IPEN-doc 14325
    Controle de qualidade e EC-sup(99m)Tc: determinacao de pureza radioquimica e investigacao da influencia de impurezas na biodistribuicao
    2009 - ALMEIDA, ERIKA V.; MONTEIRO, ELISIANE G.; ALVES, EDSON V.; SILVA, NATANAEL G. da; FUKUMORI, NEUZA T.O.; BARBOZA, MARYCEL F. de; MENGATTI, JAIR; MATSUDA, MARGARETH M.N.; VASCONCELLOS, MARINA B.A.
  • Artigo IPEN-doc 15130
    Biological profile of sup(99m)TcHYNIC-betaAlA-NT (8-13) in MDA MB-231 breast cancer cell line
    2009 - TEODORO, RODRIGO; FAINTUCH, BLUMA L.; WIECEK, DANIELLE P.; SILVA, NATANAEL G.; VALLEJO, NATALIA M.
  • Artigo IPEN-doc 15036
    Identification, control and quantification of residual sol vents in radiopharmaceutical preparations
    2009 - MARTINS, PATRICIA de A.; SILVA, JOSE L.; RAMOS, MARCELO P.S.; OLIVEIRA, IDELI M.; SILVA, NATANAEL G.; FUKUMORI, NEUZA T.O.; MATSUDA, MARGARETH M.N.
  • Artigo IPEN-doc 12029
    A challenge for the validation of the gel clot test in radiopharmaceuticals produced in the radiopharmacy center
    2007 - FUKUMORI, NEUZA T.O.; FERNANDES, ADRIANA V.; CAMPOS, DOMINGOS G. de; GOMES, ANTONIO C.; SILVA, NATANAEL G. da; PEREIRA, NILDA P.S. de; SILVA, CONSTANCIA P.G. da; MATSUDA, MARGARETH M.N.