Determinação do cetoconazol em emulsões por espectrofotometria no ultravioleta por derivada de primeira ordem e cromatografia líquida de alta eficiência

Foram desenvolvidos e padronizados métodos por espectrofotometria no ultravioleta (UV) por derivada de primeira ordem (Método I) e cromatografia líquida de alta eficiência (CLAE) (Método II) para a determinação quantitativa de cetoconazol em formulações farmacêuticas sob a forma de emulsão obtida no comércio e formulada em laboratório. A espectrofotometria no UV por derivada de primeira ordem foi padronizada usando-se o método do zero pico a 257 nm, utilizando metanol como solvente. A cromatografia líquida foi realizada empregando-se uma coluna LiChrospher® 100 RP-18 (5 µm). A fase móvel utilizada foi a mistura de trietilamina em metanol (1:500) e solução de acetato de amônio em água (1:200) na proporção de 75:25 v/v, com vazão de 1 mL/min e detecção no UV de 225 nm. O tempo de retenção do cetoconazol foi de 3,9 min e do terconazol de 5,9 min, este último utilizado com padrão interno. As curvas analíticas mostraram linearidade dentro das concentrações de 5,0 a 30,0 µg/mL para o Método I e 20,0 a 80,0 µg/mL para o Método II, com coeficientes de correlação linear de 0,9997 e 0,9981, respectivamente.O desvio padrão relativo (DPR) foi de 0,56% e 0,41% para a amostra simulada e comercial, respectivamente, empregando-se o Método I. Para o Método II, os valores foram de 2,13% e 1,25%, respectivamente. A porcentagem de recuperação foi de 100,1% para o Método I e 100,4% para o Método II. Os excipientes não interferiram nas análises. Os resultados mostraram que os dois métodos podem ser usados para a determinação rápida de cetoconazol em formulações de emulsões com precisão, exatidão e especificidade.First-derivative ultraviolet spectrophotometric (Method I) and reversed phase high performance liquid chromatographic (Method II) methods were developed. The validated methods were applied for quantitative determination of ketoconazole in commercial and simulated emulsion formulations. Quantitative first-derivative UV spectrophotometric determinations were made using the zero-crossing method at 257 nm, with methanol as background solvent. Liquid chromatographic analysis was carried out on a LiChrospher® 100 RP-18 (5µm) column. A mixture of triethylamine in methanol (1:500 v/v) and 0.5% ammonium acetate solution (75:25 v/v) was used as mobile phase at a flow rate of 1.0 mL/min with UV detection at 225 nm. The retention time of ketoconazole and terconazole were 3.9 min and 5.9 min, respectively, the later being used as internal standard. Analytical curves were linear within a concentration range from 5.0 to 30.0 µg/mL for Method I and 20.0 to 80.0 µg/mL for Method II, with correlation coefficients of 0.9997 and 0.9981, respectively. The relative standard deviation (RSD) was 0.56% and 0.41% for simulated and commercial emulsion formulations, respectively, using Method I. The corresponding values were 2.13% and 1.25%, respectively, using Method II. The percentage recoveries were above 100% for both methods. The excipients did not interfere in the analysis. The results showed that either method can be used for rapid ketoconazole determination in pharmaceutical emulsions with precision, accuracy and specificity

Determination of optimum wavelength and derivative order in spectrophotometry for quantitation of hydroquinone in creams

A espectrofotometria derivada no UV foi usada para a determinação quantitativa de hidroquinona em cremes. O objetivo desta pesquisa foi investigar o melhor comprimento de onda e a ordem da derivada, bem como validar o método proposto. Os resultados das curvas analíticas foram analisados estatisticamente pelo método dos mínimos quadrados no intervalo de 10,0 a 26,0 µg/mL, na primeira, segunda, terceira e quarta ordens da derivada. As determinações quantitativas foram realizadas utilizando os métodos "zero-crossing (Z-C)" e zero-pico (Z-P). O método proposto é simples, de baixo custo e fornece resultados confiáveis podendo ser usado no controle de qualidade de cremes contendo hidroquinona como substância ativa.UV derivative spectrophotometry was used for quantitative determination of hydroquinone in creams. The aim of this work was to investigate optimum wavelength and order of derivative, and to validate the proposed spectrophotometric method. The results of standard curves were calculated and statistically analyzed through the least squares method in the interval from 10.0 to 26.0 µg/mL, in the first, second, third and fourth order derivatives. The quantitative determination was carried out by using the zero-crossing (Z-C) and zero-peak (Z-P) methods. The proposed method is simple, of low cost and provides reliable results in order to be used in quality control of creams containing hydroquinone as active substance

Validação de um método analítico para a determinação de substâncias ativas em formulações farmacêuticas empregadas em "peelings" químicos

Chemical peeling is obtained with exfoliating formulations and is used in the treatment of actinic keratosis, wrinkles, dyschromies, acne vulgaris and rosacea acne. In this research we selected the Jessner Solution (JS), a pharmaceutical preparation composed of resorcinol (RS) (14%), salicylic acid (SA) (14%) and lactic acid (LA) (14%) in alcoholic solution and two gel samples composed of RS (30%) and SA (20%), respectively. First and second derivative UV spectrophotometric methods were developed and validated for determination of SA and RS, respectively in JS alcoholic solution, ethanol was used as background. A first derivative UV spectrophotometric method was developed for determination of these active substances in gel samples using 0.1N sulfuric acid as background. For SA in the JS, the correlation coefficient (r) was 0.9999, the precision expressed by the relative standard deviation (RSD) of 0.68% and the accuracy expressed by the average percent recovery of 100.5%. For RS in the JS, the r was 0.9999, the RSD of 0.83% and average recovery of 100.3%. In the gel of SA r was 0.9999, the mean RSD was 0.28% and average recovery of 99.3%. In the gel of RS the r was 0.9998, mean RSD was 0.34% and average recovery of 99.9%.Nos "peelings" químicos utilizam-se formulações esfoliantes, empregadas na terapêutica de queratoses actínicas, rugas, discromias pigmentares, acne vulgar e rosácea. Na presente pesquisa, foram empregadas como amostras, a solução de Jessner (SJ) composta por resorcinol (RS) 14%, ácido salicílico (AS) 14% e ácido láctico (AL) 14% em solução alcoólica e géis de AS a 20% e RS a 30%. As técnicas utilizadas foram a espectrofotometria derivada no UV de primeira e segunda ordens em etanol absoluto para o AS e RS, respectivamente na SJ, e a espectrofotometria derivada no UV de primeira ordem em ácido sulfúrico 0,1 N para o AS e RS nos géis. Para o AS na SJ, o coeficiente de correlação (r) foi de 0,9999, a precisão expressa pela média dos desvios padrão relativos (DPR) de 0,68% e a exatidão expressa pela recuperação média de 100,5%. Para o RS na SJ o r foi de 0,9999, a média dos DPR de 0,83% e a recuperação média de 100,3%. No gel de AS, o r foi de 0,9999, a média dos DPR de 0,28 e a recuperação média de 99,3%. No gel de RS, o r foi de 0,9998, a média dos DPR de 0,34 e a recuperação média de 99,9%

Comparative study on two rapid and sensitive methods for quantitative determination of tenoxicam in tablets

Tenoxicam, um análogo de piroxicam, é um AINE (Antiinflamatório Não-Esteróide). ë usado no tratamento sintomático de doenças musculoesqueléticas das juntas, tais como osteoartrite e artrite reumatóide, e, também, no tratamento de danos dos tecidos moles. Sua determinação quantitativa em formulações farmacêuticas é importante para garantir os efeitos terapêuticos desejados. O objetivo dessa pesquisa foi desenvolver, validar e comparar métodos espectrofotométrico e cromatográfico na determinação quantitativa de tenoxicam em comprimidos. Neste trabalho, comprimidos contendo 20,0 mg de tenoxicam de diferentes procedências foram analisados. O método espectrofotométrico foi validado utilizando-se 0,1 mol/L de NaOH como solvente e se obteve sinal a 368 nm. O método por CLAE foi validado utilizando-se coluna Synergi Hydri-RP® C18 (250x4,6 nm, 4µm). A fase móvel constitui-se de metanol-água (61:39 v/v), com pH ajustado para 2,5 com ácido fórmico, e velocidade de fluxo de 1,0 mL/minuto. A detecção por UV foi efetuada a 375 nm. Todas as análises foram realizadas com temperatura de coluna a 25 ºC ± 1. As curvas de calibração foram lineares na faixa de concentração de 4,0 a 24,0 µg/mL, comcoeficiente de correlação melhor que 0,9999. O limite de detecção (LD) e o limite de quantificação (LQ) foram 0,25 µg/mL e 0,90 µg/mL e 1,20 µg/mL por CLAE, respectivamente. A precisão intra e inter-dia, expressa como RSD, foi abaixo de 2% para ambos os métodos. A média de recuperação do tenoxicam ficou na faixa de 98,5 a 101,25% para o método de UV, e 99,01 a 101,93, para a CLAE. Os métodos de UV e de CLAE mostraram-se rápidos, precisos e exatos. Estatisticamente, não se observou diferença significativa entre os métodos espectrofotométricos (UV) e CLAE.Tenoxicam, a piroxicam analogue, is an NSAID (Non-Steroid Antinflamatory Drug). It is used in the symptomatic management of musculoskeletal and joint disorders such as osteoarthritis and rheumatoid arthritis, and also in the short-term management of soft-tissue injury. Its quantitative determination in pharmaceutical formulations is important to guarantee the desired therapeutic effects. The objective of this research was to develop, validate and compare spectrophotometric and chromatographic methods in the quantitative determination of tenoxicam in tablet preparations. In this work, tablets containing 20.0 mg of tenoxicam from different origins were analyzed. The spectrophotometric method was validated using 0.1 mol/L NaOH as solvent and a signal at 368 nm was taken. The HPLC method was validated using Synergi Hydro-RP® C18 column (250x4.6 mm, 4 µm). The mobile phase was constituted of methanol-water (61:39 v/v) with pH adjusted to 2.5 with formic acid, at a flow rate of 1.0 mL/min. UV detection was made at 375 nm. All analyses were performed with a column temperature of 25 °C ± 1. The calibration curves were linear over a concentration range from 4.0-24.0 µg/mL with a correlation coefficient better than 0.9999. The detection limit (DL) and quantitation limit (QL) were 0.25 µg/mL and 0.90 µg/mL for UV method and 0.35 µg/mL and 1.20 µg/mL for HPLC method respectively. The intra-day and inter-day precision expressed as RSD were below 2% for both methods. The mean recovery of tenoxicam was found to be in the range of 98.5-101.25% for UV method and 99.01-101.93% for HPLC method. The UV and HPLC methods were found to be rapid, precise and accurate. Statistically there was no significant difference between proposed UV spectrophotometric and HPLC methods

Determination of sun protection factor (SPF) of sunscreens by ultraviolet spectrophotometry

O objetivo desta pesquisa foi determinar o Fator de Proteção Solar (FPS) de emulsões contendo filtros solares físicos e químicos por espectrofotometria no ultravioleta. Foram analisadas dez amostras comerciais de emulsões de diferentes fabricantes. Os valores de FPS rotulados foram na faixa de 8 a 30. Das emulsões analisadas, 30% apresentaram valores de FPS próximos do valor rotulado, 30% apresentaram valores acima e 40% apresentaram valores abaixo do valor rotulado. O método espectrofotométrico proposto é simples e rápido para determinação preliminar in vitro do FPS de emulsões protetoras solar.The aim of this research was to determine the sun protection factor (SPF) of sunscreens emulsions containing chemical and physical sunscreens by ultraviolet spectrophotometry. Ten different commercially available samples of sunscreen emulsions of various manufactures were evaluated. The SPF labeled values were in the range of 8 to 30. The SPF values of the 30% of the analyzed samples are in close agreement with the labeled SPF, 30% presented SPF values above the labeled amount and 40% presented SPF values under the labeled amount. The proposed spectrophotometric method is simple and rapid for the in vitro determination of SPF values of sunscreens emulsions

Simultaneous determination of abamectin homologs H 2 B 1a and H 2 B 1b in gel formulation by high performance liquid chromatography

Abamectin is a drug with antiparasitic properties used in several pharmaceutical formulations. The objective of this research was to develop and validate a high performance liquid chromatographic (HPLC) method for quantification of the two abamectin homologs (H2B1a and H2B1b) in gel formulation. This HPLC method was validated using a LichroCart(r) 100 RP-18 (125 x 4 mm, 5 µm) column. The mobile phase contained of acetonitrile and water (95:5 v/v) with 1% acetic acid. The flow rate was 1.0 mL min-1 and UV detection was performed at 245 nm. Mobile phase solutions were prepared containing a nominal concentration 185.2 µg mL-1 H2B1a and 9.6 µg mL-1 H2B1b. The method displayed good linearity in the concentration range of 148.1 - 222.3 µg mL-1 and 7.7 - 11.5 µg mL-1, for H2B1a and H2B1b, respectively, with a correlation coefficient of (r)>; 0.99 for both compounds, calculated by the least mean squares method. Detection limits (DLs) were 2.8 µg mL-1 and 1.2 µg mL-1 and quantitation limits (QLs) were 8.6 µg mL-1 and 3.8 µg mL-1, for H2B1a and H2B1b, respectively. The method is simple, economical and efficient for the quantitative determination of abamectin H2B1a and H2B1b homologs in pharmaceutical preparations

Simultaneous determination of ethinyl estradiol and drospirenone in oral contraceptive by high performance liquid chromatography

A simple, rapid, economical and reliable high performance liquid chromatographic method has been developed and successfully applied in simultaneous determination of ethinyl estradiol and drospirenone in coated tablets. The HPLC method was performed on a LiChroCART® 100RP column (125x4 mm i.d., 5 µm) with acetonitrile:water 50:50 (v/v) as mobile phase, pumped at a flow rate of 1.0 mL.min-1. The fluorescence detection for ethinyl estradiol was made at λex= 280 nm and λem= 310 nm and a UV detection for drospirenone was made at 200 nm. The elution time for ethinyl estradiol and drospirenone were 4.0 and 5.7 min, respectively. The method was validated in accordance to USP 34 guidelines. The proposed HPLC method presented advantages over reported methods and is suitable for quality control assays of ethinyl estradiol and drospirenone in coated tablets.Um método simples, rápido, econômico e confiável foi desenvolvido empregando a cromatografia líquida de alta eficiência para a determinação simultânea de etinilestradiol e drospirenona em comprimidos revestidos. O método foi realizado utilizando coluna LiChroCART® 100RP (125 x 4 mm d.i., 5 µm), a fase móvel constituída de acetonitrila:água, 50:50 (v/v) com vazão de 1,0 mL.min-1. A detecção foi realizada empregando fluorescência em λex= 280 nm e λem= 310 nm para o etinilestradiol e na região de UV em 200 nm para a drospirenona. O etinilestradiol e a drospirenona tiveram tempo de retenção de 4,0 e 5,7 min, respectivamente. O método foi validado de acordo com as diretrizes da USP 34. O método proposto apresentou vantagens sobre os relatados na literatura e pode ser considerado adequado para o controle de qualidade do etinilestradiol e da drospirenona em comprimidos revestidos

DERIVATIVE SPECTROPHOTOMETRIC METHOD FOR DEYERMINATION OF ACYCLOVIR IN POLYMERIC NANOPARTICLES

A derivative spectrophotometric method was validated for quzintification of acyclovir in poly (n-butylcyanoacrylate) (PBCA) nanoparticles. Specificity, linearity. precision, accuracy, recovery. detection (LOD) and quantification (LOQ) Inuits were established for method validation. First-derivative it 295.2 nm eliminated interferences from nanoparticle ingredients and presented linearity for acyclovir concentrations ranging front 1.25 to 40.0 mu g/mL. (r = 0.9999). Precision and accuracy data demonstrated good reproducibility. Recovery ranged from 99.3 to 101.2. LOD) was 0.08 mu g/mL and LOQ. 0.25 mu g/mL. Thus. the proposed method proved to be easy. low cost. and accurate, and therefore, an useful alternative to quantify acyclovir in nanoparticles.CNPqCNPqCAPESCAPE

Determination of Atropine Enantiomers in Ophthalmic Solutions by Liquid Chromatography Using a Chiral AGP (R) Column

Many therapeutic agents are commercialized under their racemic form. The enantiomers can show differences in the pharmacokinetic and pharmacodynamic profile. The use of a pure enantiomer in pharmaceutical formulations may result in a better therapeutic index and fewer adverse effects. Atropine, an alkaloid of Atropa belladonna, is a racemic mixture of l-hyoscyamine and d-hyoscyamine. It is widely used to dilate the pupil. To quantify these enantiomers in ophthalmic solutions, an HPLC method was developed and validated using a Chiral AGP (R) column at 20 degrees C. The mobile phase consisted of a buffered phosphate solution (containing 10 mM 1-octanesulfonic acid sodium salt and 7.5 mM triethylamine, adjusted to pH 7.0 with orthophosphoric acid) and acetonitrile (99 + 1, v/v). The flow rate was 0.6 mL/min, with UV detection at 205 nm. In the concentration range of 14.0-26.0 mu g/mL, the method was found to be linear (r > 0.9999), accurate (with recovery of 100.1-100.5%), and precise (RSD system: <= 0.6%; RSD intraday: <= 1.1%; RSD interday: <= 0.9%). The method was specific, and the standard and sample solutions were stable for up to 72 h. The factorial design assures robustness with a variation of +/-10% in the mobile phase components and 2 degrees C of column temperature. The complete validation, including stress testing and factorial design, was studied and is presented in this research