Use of charge-transfer complexation in the spectrophotometric analysis of certain cephalosporins

Saleh, Gamal A.; Askal, Hassan F.; Radwan, Mohamed F.; Omar, Mahmoud A.

doi:10.1016/s0039-9140(01)00409-x

Cited by 85 publications

(44 citation statements)

References 15 publications

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“…Por sua vez, a literatura cientí-fica relata o desenvolvimento de outros métodos analíticos para este fim em que outras técnicas analíticas são empregadas tais como a espectrofluorimetria, 5 a quimioluminescência, 6,7 , a eletroforese capilar 8 e a espectrofotometria. [9][10][11][12][13][14] Ainda, outros vários métodos baseados na cromatografia a líquido de alta eficiência já foram relatados para este fim. [15][16][17] Entretanto, estes métodos cromatográficos são caracterizados pela baixa produtividade e pelo alto custo da instrumentação, quando comparados com os métodos espectrofotométricos.…”

Section: Introductionunclassified

Determinação espectrofotométrica de cefalexina em formulações farmacêuticas explorando a sua reação de transferência de carga com a quinalizarina

Paula¹,

Almeida²,

Cassella³

2010

Quím. Nova

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Recebido em 16/9/09; aceito em 8/12/09; publicado na web em 25/3/10 SPECTROPHOTOMETRIC DETERMINATION OF CEPHALEXIN IN PHARMACEUTICAL FORMULATIONS EXPLORING ITS CHARGE TRANSFER REACTION WITH QUINALIZARIN. This work proposes a new simple and fast spectrophotometric method for cephalexin determination in pharmaceutical formulations. The method is based on the charge transfer reaction between cephalexin and quinalizarin in dimethylsulfoxide medium. Several analytical parameters related to the system were optimized and the reaction was characterized in terms of stoichiometry. Also, association constant and apparent molar absorptivity of the product were determined. The method presented a limit of detection of 0.46 mg L -1 and a quantification limit of 1.5 mg L -1. It was successfully applied in the determination of cephalexin in two samples of commercial pharmaceutical formulations.Keywords: cephalexin; charge transfer reaction; spectrophotometry. INTRODUÇÃOA primeira fonte das cefalosporinas, Cephalosporium acremonium, foi isolada em 1948 a partir do micro-organismo denominado Brotzu do mar, em uma localidade próxima a uma saída de esgoto na costa da Sardenha, Itália. Foi constatado que os filtrados não tratados de cultura destes micro-organismos inibiam in vitro o crescimento de Staphilococcus aureus. Posteriormente, verificou-se que os líquidos de culturas nos quais o fungo da Sardenha era cultivado continham três antibióticos distintos, que foram denominados inicialmente de cefalosporina P, N e C. Com o isolamento do núcleo ativo da cefalosporina C, o ácido 7-aminocefalosporânico, e com o acréscimo de cadeias laterais, foi possível produzir substâncias semissintéticas com uma atividade antibacteriana muito maior do que a substância original. A partir desta constatação foram produzidas as cefalosporinas de primeira geração, entre estas a cefalexina (ácido 7-(D-2-amino-2-fenilacetamido)-3-metil-8-oxo-5-tia-1-azabiciclo [4.2.0]oct-2-eno-2-carboxílico), um antibiótico largamente utilizado na medicina humana para o combate de diversos tipos de infecções. A cefalexina (Figura 1) é extensamente comercializada no Brasil, uma vez que está presente em diversas formulações farmacêuticas de diferentes fabricantes. 1No Brasil, atualmente, a automedicação constitui-se em um grave problema de saúde pública. Os antibióticos aparecem em segundo lugar entre os medicamentos mais utilizados pela população, sendo superados apenas pelos analgésicos. No caso dos antibióticos, o seu uso exagerado, entre outros fatores, pode levar ao aumento da resistência bacteriana, tornando o medicamento cada vez mais ineficaz no tratamento da infecção.2 Neste contexto, o controle rigoroso das quantidades administradas aos pacientes pode ser considerado um assunto de importância social e econômica. Sem dúvida alguma, um dos aspectos importantes deste processo diz respeito ao controle das quantidades de princípios ativos presentes em medicamentos comerciais, o que exige o desenvolvimento de metodologias analíticas rápidas, simples, baratas e confiáveis...

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Section: Introductionunclassified

Determinação espectrofotométrica de cefalexina em formulações farmacêuticas explorando a sua reação de transferência de carga com a quinalizarina

Paula¹,

Almeida²,

Cassella³

2010

Quím. Nova

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“…DDQ is a π-acceptor which reacts instantaneously with basic nitrogenous compounds to form a chargetransfer complex of n-π type [13][14][15][16][17][18] . The spectrum of DDQ in the acetonitrile mixture exhibits an absorption band at 372 nm.…”

Section: Reaction Of Ra With Ddqmentioning

confidence: 99%

“…In the 1 H NMR spectra of the complex, generally the protons of the donor are shifted to downfield (paramagnetic shift) [14][15][16][17][18] . The 1 H NMR spectra of the charge transfer complex of RA with DDQ as an accepwww.scienceasia.org tor was recorded in d 6 -DMSO along with the spectra of the free drug (Fig.…”

Section: Spectroscopic Investigations For the Structure Of Charge Tramentioning

confidence: 99%

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Khan¹,

Chaudhary²,

Patro³

et al. 2009

ScienceAsia

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A simple, sensitive spectrophotometric method was developed for the determination of rabeprazole sodium (RA) in pure form and for pharmaceutical formulations. The charge transfer interaction between RA and 2,3-dichloro-5,6-dicyano-p-benzoquinone (DDQ) as an acceptor was investigated spectrophotometrically. Variables affecting the reaction were studied and optimized. The proposed method was applied successfully to the determination of RA in its pure form and pharmaceutical dosage forms with good accuracy and precision. The formation of charge transfer complex and the site of interaction was confirmed by using UV-Visible spectrophotometry, FT-IR spectrometry, and 1 H NMR techniques. Based on Job's method of continuous variation plots, the obtained results indicate the formation of 1:1 charge transfer complex with a general formula [(RA) (DDQ)]. Statistical comparison of the results with the reference method shows excellent agreement and indicates no significant differences in accuracy or precision.

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“…10 Cefazolin sodium has some analytical methods described in official compendia such as British, 11 European, 12 Japanese, 13 Portuguese 14 and US 15 pharmacopeias. In the literature, several methods have been described for the qualitative 16 and quantitative analysis of cefazolin sodium, included spectrophotometry, [17][18][19][20][21][22][23][24][25][26][27][28][29] high-performance liquid chromatography [30][31][32][33][34][35][36][37][38][39][40][41][42][43][44][45][46][47] and voltammetry. 48 However, most of them were time-consuming and dedicated to sophisticated and expensive analytical instruments.…”

Section: Introductionmentioning

confidence: 99%

New Environmentally Friendly Method for Quantification of Cefazolin Sodium

Rechelo¹,

Fernandes²,

Kogawa³

et al. 2017

ECB

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Cefazolin sodium, a β-lactam antimicrobial agent belonging to the first generation cephalosporins, has a broad spectrum of action, acting against gram positive and gram negative bacteria. Stands out over other cephalosporins for its ability to also act against some species of Enterobacter, and have a long half-life, thus reducing the frequency of administrations. A simple, fast and reproducible method by visible spectrophotometry was developed and validated for quantification of cefazolin sodium in the lyophilized powder. This technique is widely used in the pharmaceutical industry due to its ease of execution, low cost, safety and high precision and accuracy. It has been employed in the quality control routine of numerous pharmaceuticals in order to identify them and quantify their active principles. The method was capable of detecting and quantifying the cefazolin sodium obtaining satisfactory results regarding selectivity, precision, accuracy and robustness, on linear range of 32.0 to 92.0 µg mL -1 , showing the correlation coefficient of 0.9993 when analyzed at 767 nm. Due to the environmental impacts caused by global economic development, green chemistry has come up with a proposal to minimize and/or eliminate the use of harmful solvents, which generate large amounts of toxic waste to the environment and the health of operators, as well as reducing expenses with costly processes. The proposed method does not use toxic solvent, proving to be effective, low cost, easy to apply and safe for the analyst and environment. *Corresponding AuthorsFax: +55 16 3301 6967 E-Mail: ac_kogawa@yahoo.com.br [a]

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Use of charge-transfer complexation in the spectrophotometric analysis of certain cephalosporins

Cited by 85 publications

References 15 publications

Determinação espectrofotométrica de cefalexina em formulações farmacêuticas explorando a sua reação de transferência de carga com a quinalizarina

Determinação espectrofotométrica de cefalexina em formulações farmacêuticas explorando a sua reação de transferência de carga com a quinalizarina

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New Environmentally Friendly Method for Quantification of Cefazolin Sodium

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