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Previous issue date: 2011-07-07 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior / The present study utilized the thermogravimetry (TG) and optical emission
spectroscopy with inductively coupled plasma - ICP / OES to determine the calcium content
in tablets of carbonate, citrate and calcium lactate used in the treatment of osteoporosis. The
samples were characterized by IR, SEM, TG / DTG, DTA, DSC and XRD. The thermal
analysis evaluated the thermal stability and physical-chemical events and showed that the
excipients influence the decomposition of active ingredients. The results of thermogravimetry
indicated that the decomposition temperature of the active CaCO3 (T = 630.2 ?C) is lower
compared to that obtained in samples of the tablets (633.4 to 655.2 ?C) except for sample AM
2 (Ti = 613.8 oC). In 500.0 ?C in the samples of citrate and calcium lactate, as well as their
respective active principles had already been formed calcium carbonate. The use of N2
atmosphere resulted in shifting the initial and final temperature related to the decomposition
of CaCO3. In the DTA and DSC curves were observed endo and exothermic events for the
samples of tablets and active ingredients studied. The infrared spectra identified the main
functional groups in all samples of active ingredients, excipients and tablets studied, such as
symmetric and asymmetric stretches of the groups OH, CH, C = O. Analysis by X-ray
diffraction showed that all samples are crystalline and that the final residue showed peaks
indicative of the presence of calcium hydroxide by the reaction of calcium oxide with
moisture of the air. Although the samples AM 1, AM 2, AM 3 and AM 6 in
their formulations have TiO2 and SiO2 peaks were not observed in X-ray diffractograms of
these compounds. The results obtained by TGA to determine the calcium content of the drugs
studied were satisfactory when compared with those obtained by ICP-OES. In the AM 1
tablet was obtained the content of 35.37% and 32.62% for TG by ICP-OES, at 6 AM a
percentage of 17.77% and 16.82% and for AM 7 results obtained were 8.93% for both
techniques, showing that the thermogravimetry can be used to determine the percentage of
calcium in tablets. The technique offers speed, economy in the use of samples and procedures
eliminating the use of acid reagents in the process of the sample and efficiency results. / O presente trabalho utilizou a termogravimetria (TG) e a espectroscopia de emiss?o
?ptica com plasma indutivamente acoplado ICP/OES para determinar o teor de c?lcio em
medicamentos ? base de carbonato, citrato e lactato de c?lcio usados no tratamento da
osteoporose. As amostras foram caracterizadas por IV, MEV, TG/DTG, DTA, DSC e DRX.
As t?cnicas termoanal?ticas avaliaram a estabilidade t?rmica e os eventos f?sicos-qu?micos e
mostraram que os excipientes interferem na decomposi??o dos princ?pios ativos. Os
resultados da Termogravimetria indicaram que a temperatura de decomposi??o do CaCO3
princ?pio ativo (T = 630,2 ?C) ? inferior em compara??o as amostras dos comprimidos (633,4
a 655,2 ?C), exceto para a amostra AM 2 (Ti = 613,8 oC). Em 500,0 ?C nas amostras de
citrato e lactato de c?lcio, assim como nos seus respectivos princ?pios ativos j? havia sido
formado o carbonato de c?lcio. A utiliza??o da atmosfera de N2 provocou deslocamento nas
temperaturas inicial e final relacionadas ? decomposi??o do CaCO3. Nas curvas DTA e DSC
foram observados eventos endo e exot?rmicos para as amostras dos medicamentos e
princ?pios ativos analisados. Os espectros de infravermelho identificaram os principais grupos
funcionais existentes em todas as amostras de princ?pios ativos, excipientes e comprimidos
estudados, tais como estiramentos sim?tricos e assim?tricos dos grupos O-H, C-H, C=O. As
an?lises por difra??o de raios-x mostraram que todas as amostras apresentam cristalinidade e
que os res?duos finais mostraram picos indicativos da presen?a de hidr?xido de c?lcio devido
? rea??o do ?xido de c?lcio com a umidade do ar. Embora os medicamentos AM 1, AM 2,
AM 3 e AM 6 tenham em suas formula??es TiO2 e SiO2 n?o foram observados picos nos
difratogramas de raios-x desses compostos. Os resultados obtidos por TG para determinar o
teor de c?lcio dos medicamentos estudados mostraram-se satisfat?rios quando comparados
aos obtidos pelo ICP-OES. No comprimido AM 1 foi obtido um teor de 35,37 % pela TG e
32,62 % pelo ICP-OES, na AM 6 obteve-se um percentual de 17,77 % e 16,82 % e para a AM
7 os resultados obtidos foram de 8,93 % para ambas as t?cnicas, mostrando que a
termogravimetria pode ser utilizada na determina??o do teor de c?lcio em medicamentos, pois
a t?cnica oferece rapidez, economia no uso das amostras e procedimentos, elimina??o do uso
de reagentes ?cidos no processo de abertura de amostra e efici?ncia nos resultados.
Identifer | oai:union.ndltd.org:IBICT/oai:repositorio.ufrn.br:123456789/17647 |
Date | 07 July 2011 |
Creators | Souza, Sheila Pricila Marques Cabral de |
Contributors | CPF:44420773472, http://lattes.cnpq.br/9563490368583906, Moura, Maria de F?tima Vit?ria de, CPF:31482015404, http://lattes.cnpq.br/2959800336802498, Huitle, Carlos Alberto Martinez, CPF:01139059980, http://lattes.cnpq.br/2485073932883264, Leles, Maria In?s Goncalves, CPF:22049258372, http://lattes.cnpq.br/1614912440064013, Fernandes, Nedja Suely |
Publisher | Universidade Federal do Rio Grande do Norte, Programa de P?s-Gradua??o em Qu?mica, UFRN, BR, F?sico-Qu?mica; Qu?mica |
Source Sets | IBICT Brazilian ETDs |
Language | Portuguese |
Detected Language | English |
Type | info:eu-repo/semantics/publishedVersion, info:eu-repo/semantics/masterThesis |
Format | application/pdf |
Source | reponame:Repositório Institucional da UFRN, instname:Universidade Federal do Rio Grande do Norte, instacron:UFRN |
Rights | info:eu-repo/semantics/openAccess |
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