Determination of carbamazepine in pharmaceutical formulations

Solon, Lilian Grace da Silva; Oliveira, Ana Isabel Maia de; Guerra, Gerlane Coelho Bernardo; Soares, Luiz Alberto Lira; Araújo, Aurigena Antunes de

doi:10.1590/s1984-82502010000300014

Cited by 4 publications

(4 citation statements)

References 8 publications

(11 reference statements)

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Evaluation of the hydration and dehydration behavior of pharmaceutical substances is important for the development of stable formulations, because the anhydrous and hydrated forms of a drug can show differences in their physicochemical characteristics. Properties including heat capacity, density, crystal structure, chemical stability, hygroscopicity, powder flow, and dissolution rate ultimately affect the bioavailability of a drug (Solon et al, 2010;Ono et al, 2002;McMahon et al, 1996;Qu, Louhi-Kultanen, Kallas, 2006).…”

Section: Introductionmentioning

confidence: 99%

Thermoanalytical studies of carbamazepine: hydration/dehydration, thermal decomposition, and solid phase transitions

Pinto¹,

Ambrozini²,

Ferreira³

et al. 2014

Braz. J. Pharm. Sci.

View full text Add to dashboard Cite

Carbamazepine (CBZ), a widely used anticonvulsant drug, can crystallize and exhibits four polymorphic forms and one dihydrate. Anhydrous CBZ can spontaneously absorb water and convert to the hydrate form whose different crystallinity leads to lower biological activity. The present study was concerned to the possibility of recovering the hydrated form by heating. The thermal behavior of spontaneously hydrated carbamazepine was investigated by TG/DTG-DTA and DSC in dynamic atmospheres of air and nitrogen, which revealed that the spontaneous hydration of this pharmaceutical resulted in a Form III hydrate with 1.5 water molecules. After dehydration, this anhydrous Form III converted to Form I, which melted and decomposed in a single event, releasing isocyanic acid, as shown by evolved gas analysis using TG-FTIR. Differential scanning calorimetry analyses revealed that Form III melted and crystallized as Form I, and that subsequent cooling cycles only generated Form I by crystallization. Solid state decomposition kinetic studies showed that there was no change in the substance after the elimination of water by heating to 120 °C. Activation energies of 98 ± 2 and 93 ± 2 kJ mol -1 were found for the hydrated and dried samples, respectively, and similar profiles of activation energy as a function of conversion factor were observed for these samples. Uniterms:Carbamazepine/thermal analysis. Polymorphism. Hydrate. Dehydration.A carbamazepina (CBZ) é um anticonvulsivante frequentemente utilizado no Brasil e em vários países. Ela apresenta quatro formas polimórficas e um diidrato. Todas as formas são ativas farmacologicamente, porém a Forma III é a preferível do ponto de vista farmacêutico, em função de suas propriedades físico-químicas. Entretanto, essa forma é altamente higroscópica, podendo converter-se ao diidrato, menos ativo biologicamente. Nesse trabalho propõe-se avaliar o comportamento térmico da forma hidratada, visando à recuperação da forma ativa, por aquecimento. Para tanto, foi feito um estudo do comportamento térmico por TG/DTG-DTA e DSC em atmosfera dinâmica de ar e nitrogênio, que evidenciou hidratação espontânea da Forma III, gerando um hidrato contendo 1,5 moléculas de água. Essa forma sofre desidratação, seguida de fusão e conversão para a Forma I. Segue-se a decomposição em uma única etapa, na qual ocorre liberação do ácido isociânico, conforme análise de gases evolvidos, por termogravimetria acoplada ao infravermelho (TG-FTIR). Estudos por calorimetria exploratória diferencial mostraram que a Forma III se funde e se cristaliza imediatamente na Forma I, durante o aquecimento. A Forma I também se funde e ciclos de aquecimento/resfriamento posteriores evidenciaram que a substância se cristaliza apenas na Forma I por resfriamento. Estudos cinéticos da decomposição, em estado sólido, mostraram que não há alteração na substância pela eliminação da água por aquecimento, sendo determinados valores de energia de ativação da ordem de 98 ± 2 e 93 ± 2 kJ mol -1 , respectivamente, para a amostra hidratada e submeti...

show abstract

Section: Introductionmentioning

confidence: 99%

Thermoanalytical studies of carbamazepine: hydration/dehydration, thermal decomposition, and solid phase transitions

Pinto¹,

Ambrozini²,

Ferreira³

et al. 2014

Braz. J. Pharm. Sci.

View full text Add to dashboard Cite

show abstract

“…The contents of Brand A, an innovator brand, conformed to the standard (BP 2002) while that of Brands B and C did not conform (Table 4). Bioavailability is the fraction of the administered drug which reaches the blood stream from the gastrointestinal tract (Solon et al, 2010). Thus, the amount of the active ingredient presence in a drug is one of the determinants of bioavailabilty.…”

Section: Discussionmentioning

confidence: 99%

“…Thus, it imposes a large economic burden on global health care systems and is a major public health problem in low and middle-income countries (Mbuba and Newton, 2009). Carbamazepine is used in the treatment of trigeminal and glossopharyngeal nerve neuralgia, acting by reducing repetitive activation of the action potential (Solon et al, 2010). It is considered one of the best anticonvulsant, producing less psychological alterations and behavior effects (Castro et al, 2010).…”

Section: Introductionmentioning

confidence: 99%

“…It is considered one of the best anticonvulsant, producing less psychological alterations and behavior effects (Castro et al, 2010). Previous study was conducted by Solon et al, (2010) to evaluate the physico-chemical quality control of some formulations of carbamazepine. This study was aimed to assay the chemical contents and some physical parameters of three brands of carbamazepine; by determining possible relationship between the chemical equivalence of the brands and the outcomes of seizure protection in chicks, using maximal electroshock test.…”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Chemical equivalence assessment of three brands of carbamazepine tablets and their anticonvulsant outcome on electrically-induced seizures in chicks

Malami¹,

Usman²,

Shehu³

et al. 2016

Bayero J. Pure App. Sci.

View full text Add to dashboard Cite

Assay for content of active ingredients is a critical test of drug quality; failure to meet up the standard for content of active ingredients will result to sub therapeutic quantities. Three brands (A, B and C) of carbamazepine were assayed to determine their chemical equivalence as well as their anticonvulsant activities. This was aimed at determining the possible relation between the chemical equivalence of the brands and their anticonvulsant outcomes. The brands were randomly selected from Community Pharmacies in Zaria, Kaduna State, and assayed for chemical equivalence to establish weight uniformity and identity; percentage content of active ingredients, using UV spectrophotometric analysis. Similarly all the brands were evaluated for anticonvulsant activity using maximal electroshock seizure model in chicks at doses of 20, 10 and 5 mg/kg. All the brands passed weight uniformity test as none of the tablets deviated from the mean by more than 7.5%. Similarly, their melting points were found to conform to standard average melting point (191 o C) according to B.P. official monograph. However, the content of the active ingredients for Brands B and C did not conform to official standard of 95-105% while brand A conformed. Thus, the percentage contents for brands A, B and C were 99.49%, 76.02% and 87.59% respectively. Also, all the brands at the tested doses offered protection against seizures, ranging from 70-100%; but Brand C at 5 mg/kg offered only 40% quantal protection. The three brands of carbamazepine tablets were not chemically equivalent and their chemical equivalence indices could not be said to be the determinant of anticonvulsant effect.

show abstract

Application of cation-modified sulfur nanoparticles as an efficient sorbent for separation and preconcentration of carbamazepine in biological and pharmaceutical samples prior to its determination by high-performance liquid chromatography

Ghoraba

Aibaghi

Soleymanpour

2017

Journal of Chromatography B

View full text Add to dashboard Cite

Determination of carbamazepine in pharmaceutical formulations

Cited by 4 publications

References 8 publications

Thermoanalytical studies of carbamazepine: hydration/dehydration, thermal decomposition, and solid phase transitions

Thermoanalytical studies of carbamazepine: hydration/dehydration, thermal decomposition, and solid phase transitions

Chemical equivalence assessment of three brands of carbamazepine tablets and their anticonvulsant outcome on electrically-induced seizures in chicks

Application of cation-modified sulfur nanoparticles as an efficient sorbent for separation and preconcentration of carbamazepine in biological and pharmaceutical samples prior to its determination by high-performance liquid chromatography

Contact Info

Product

Resources

About