Spectrophotometric determination of rosuvastatin in pharmaceutical formulations using quinalizarin

ABSTRACT This work presents the development of a methodology based on the formation of a charge transfer complex between quinalizarin and rosuvastatin, allowing for the spectrophotometric determination of rosuvastatin at 579 nm. The factors involved in the sensitivity of the technique were studied (nature and proportion of the solvent, reaction time, pH of aqueous phase and quinalizarin concentration). The proposed spectrophotometric procedures were validated with respect to linearity, ranges, precision, accuracy, detection and quantification limits. Calibration curves of the formed color products showed good linear relationships over the concentration range of 6-15 mg L-1. The proposed method has been successfully applied, which can be confirmed by interference test (comparison between the standard curves and addition of analyte), method precision (RSD 2.3% to 6 mg L-1), and by accuracy (statistically equivalent results between the proposed method and a chromatographic method of reference).

Prevalence of hemoglobinopathies in school children: the importance of using confirmatory methods / Prevalência das hemoglobinopatias em crianças em idade escolar: a importância do uso de métodos de confirmação

The hemoglobinopathies are included among the most common genetic diseases in the world. In Brazil, hemoglobinopathies are related to the diversity of racial backgrounds and the degree of interbreeding. The study focused on the prevalence of hemoglobinopathies using conventional and confirmatory laboratory tests in children from public schools in Ribeirão Preto-SP. The study involved the participation of 427 children between six and nine years of age. Hematologic evaluation, hemoglobin electrophoresis on cellulose acetate at alkaline pH, quantification of hemoglobin fractions by high performance liquid chromatography (HPLC) and detection of -α^3.7 deletion for α thalassemia by polymerase chain reaction were performed. The results of hemoglobin electrophoresis on cellulose acetate and HPLC of the children studied showed the presence of 30 children (7%) with hemoglobinopathies. Eleven children presented results indicating suspicion of S/β-thalassemia; their parents and/or siblings were evaluated and confirmed the presence of only Hb S. The analysis of deletion -α^3.7to characterize α-thalassemias sampling performed on 207 participants identified 26 children (12.6%) with deletion -α^3.7. Thus, 54 (12.6%) of the children studied present this genetic alteration. For the detection of α-thalassemias it is necessary to use confirmatory methods such as molecular analysis and evaluation of family members in doubtful cases to facilitate genetic counseling in families, in which deletion -α^3.7 is more frequent in Brazil...

As hemoglobinopatias estão incluídas nas doenças genéticas mais comuns no mundo. No Brasil, as hemoglobinopatias são relatadas pela diversidade racial e o grau de miscigenação. O estudo focou a prevalência das hemoglobinopatias usando métodos laboratoriais convencionais como a eletroforese de hemoglobina em acetato de celulose em pH alcalino e confirmatório por reação em cadeia de polimerase (PCR) em crianças de escolas públicas de Ribeirão Preto-SP. O estudo envolveu a participação de 427 crianças entre 6-9 anos de idade. Determinaram-se os valores hematológicos, efetuou-se eletroforese de hemoglobina em acetato de celulose em pH alcalino, quantificação das frações de hemoglobina por HPLC e a detecção da deleção -α^3,7 pela PCR. Os resultados da eletroforese de hemoglobina em acetato de celulose e do HPLC, nas crianças estudadas, mostraram a presença de 30 crianças (7%) com hemoglobinopatias. Onze crianças apresentaram resultado indicando a suspeita de S/β-talassemia; seus pais e/ou irmãos confirmaram a presença de apenas a Hb S. A análise da deleção -α^3,7, uma das alterações que estão presentes na α-talassemia, realizada em 207 participantes, identificou 26 crianças (12,6%) com a deleção -α^3,7. Dessa forma, 54 (12,6%) das crianças estudadas apresentam hemoglobinopatias. Para a deleção da α-talassemias é necessário utilizar métodos confirmatórios como as análises moleculares e avaliação de membros da família, em casos duvidosos, facilitando o aconselhamento genético nas famílias, sendo a deleção -α^3,7 mais frequente no Brasil...

Development of methodologies for dimethylaminoethanol glycolate assay in association with sunscreens in dermocosmetic formulation

DMAE glycolate (DG) and sunscreens have been used associated in anti-aging dermocosmetic formulations. Despite extensive use of these substances, methods for quantification of DG as raw material and in cosmetic formulations, especially when associated, are not described in the literature. RP-HPLC and non-aqueous titration methods, with determination potentiometric end-point (PT), were developed and validated for rapid assay of DG as raw material and in a topic emulsion in association with sunscreens. Both methods are simple, selective, linear, accurate and precise. The PT method was chosen for stability study of DG in the formulation developed. The proposed formulation presented good stability performance as regards aspect, pH, apparent viscosity, and SPF, with less than 5% of DG degradation compared to initial conditions.

Glicolato de DMAE (DG) e protetores solares têm sido utilizados associados em formulações dermocosméticas antiidade. Apesar da ampla utilização dessas substâncias, métodos de quantificação para DG matéria-prima e em formulações cosméticas, especialmente quando associados, não estão descritos na literatura. Neste trabalho foram desenvolvidas e validadas metodologias por CLAE-FR e titulação em meio não-aquoso, com determinação do ponto final por potenciométrica (TP), para a rápida análise de DG matéria-prima e em emulsão tópica em associação com fotoprotetores. Ambos os métodos são simples, seletivos, lineares, exatos e precisos. O método TP foi escolhido para o estudo da estabilidade do DG na formulação desenvolvida. A formulação proposta apresentou um bom desempenho no que se refere a estabilidade, aspecto, pH, viscosidade aparente e SPF, com menos de 5% degradação do DG comparado as condições iniciais.

Qualitative and quantitative estimation of phenytoin in hair of epileptic patients by thin layer chromatography [TLC] and high performance liquid chromatpgraphy [HPLC]

The Two methods [TLC and HPLC] were applied to the head hair of epileptic patients who are orally treated with 100, 150, 200 and 300 mg of phenytoin daily. The detection of phenytoin in human hair revealed that, by TLC phenytoin was present in all hair samples. Zwikker's reagent and the dithiazone reagent were the best spraying reagents when the eluent was methanol to chloroform 1:9 by HLPC, phenytoin was present in hair samples at concentrations ranged from 4.3-9.5 ng/mg after administration of 100-300 mg/day of phenytoin respectively with a retention time 6.16 min when the mobile phase was Acetonitrile 70% to methanol 30%. The results show a linear correlation between the drug concentration in human hair and the daily dosage of phenytoin

HPLC determination of polymyxin-B-sulphate, gramicidin and benzalkonium chloride in pharmaceutical formulations

A rapid and sensitive method is described for the determination of gramicidin, polymyxin-B-sulphate and benzalkonium chloride in pharmaceutical preparations using high-performance liquid chromatography. The analysis was performed on 5u-Nuclosil-cyano 250x4.6mm column, water [pH 1.9 with perchloric acid]: Acetonitrile: Isopropanol [60: 30: 15] as a mobile phase, detection at 214nm and at 35[degree]C. The method was applied on Neo-myxidin Eye Drops which contains the same concentrations of this mixture and the results are in agreement with manufacture's specification. With good accuracy and precision as shown from the percentage recovery and relative standard deviation from 0.2 to 1.64%

Spectrofluorimetric determination of bisoprolol fumarate and valsartan in tablets and spiked plasma

Simple, sensitive and rapid spectrofluorimetric procedure is described for the determination of two antihypertensive drugs namely, Bisoprolol fumarate [BSF] and Valsartan [VT]. The effect of solvents was investigated. The fluorescence properties of the two cited drugs showed maximum emission intensity in 0.1N H[2]SO[4] at lambda [em] 298 and 415nm for BSF and VT, respectively, when excited at lambda[ex] 227nm. The calibration graphs were rectilinear from 0.08-1.28 and 0.12-1.6 micro g/ml for BSF and VT respectively. The method, was applied to the determination of the two cited drugs in tablets either single or when co-formulated with hydrochlorothiazide [HZ] with % recoveries of 100.03 +/- 0.57 and 99.70 +/- 0.90 for BSF and VT, respectively. Furthermore, the high sensitivity of the proposed method it allowed its application in spiked human plasma with good % recoveries of 99.73 +/- 2.06 for BSF and 99.94 +/- 1.71 for VT

Main phenolic compound of petals of Echium Amoenum fisch. and C. A. mey., a famous medicinal plant of Iran

Echium amoenum Fisch. and C.A. Mey. [Boraginaceae] is an indigenous Iranian plant, that its dry violet-blue petals [Gol-e-Gavzaban] have long been used in traditional medicine of Iran. In this study concentrated metanolic extract of the grounded dried petals of E. amoenum was fractionated by column chromatography and the fractions were purified by preparative HPLC. The structure of main pure component which was characterized by UV, IR, one and two dimensional 1H and 13C-NMR and Mass spectroscopy was found to be rosmarinic acid which is widespread in the plants of the Lamiaceae and Boraginaceae families in insignificant quantities and has antimicrobial, antiviral, and anti-inflammatory effects

Retinol sérico en mujeres mexicanas urbanas durante el periodo perinatal / Serum retinol in urban Mexican women during the perinatal period

Objetivo. Establecer la prevalencia de deficiencia de vitamina A durante el embarazo y la lactancia en un grupo de mujeres mexicanas urbanas. Material y métodos. Se invitó a participar a un grupo de gestantes que acudián a control prenatal, que carecían de patología agregada y contaban con menos de 20 semanas de embarazo. Fueron evaluadas tres veces durante el embarazo y hasta la semana 24 del posparto. La determinación de vitamina A en suero se realizó por cromatografía de líquidos de alta presión. Se consideró como punto de corte para riesgo de deficiencia una concentración de retinol > 1.05 µmol/L. Resultados. En las tres evaluaciones durante la gestación las concentraciones de vitamina A fueron de 2.34 ñ 0.70, 2.41 ñ 1.03 y 1.86 ñ 0.66 µmol/L, respectivamente, lo cual muestra una disminución significativa. Sin embargo sólo 1/30 se ubicó por debajo del punto de corte aceptado para considerar riesgo de deficiencia y ninguno para deficiencia. Durante el posparto las concentraciones se conservaron relativamente constantes, alrededor de 2.10 µmol/L. La práctica de la lactancia no tuvo impacto sobre las concentraciones séricas de retinol, no así la pérdida de peso. Conclusiones. En la población estudiada no se documentaron casos de deficiencia de vitamina A durante el periodo perinatal. La pérdida de peso materna tiene influencia sobre las concentraciones de retinol en el posparto

Application of high performance liquid chromatography to the analysis of some non-volatile coffee components

High performance liquid chromatography (HPLC) was applied to the analysis of caffeine, trigonelline, nicotinic acid and sucrose in Arabica an Robusta coffee. Green and roasted coffee samples were used in this study and the degradation of sucrose and trigonelline, with the formation of nicotinic acid, was followed during roasting. Caffeine did not undergo significant degradation with only 5.4% being lost under severe roasting. Sucrose was degraded rapidly during processing with light roasting producing a 97% loss and dark roasting degrading it completely. Loss of trigonelline was strongly dependent on the degree of roasting being higher in the Robusta coffee. Trigonelline degradation was associated with nicotinic acid formation both in the Arabica and Robusta coffees as a consequence of the roasting process. Trigonelline and sucrose were determined simultaneously by partition chromatography and detection with the mass detector. Determination of caffeine was carried out using reversed phase chromatography and nicotinic acid by ion-pair reversed phase chromatography. Detection in both cases was achieved using an ultraviolet detector at 272nm or 254nm, respectively. HPLC showed adequate precision and accuracy for routine analyses. In addition, the methods used were more rapid and simple than traditional procedures. HPLC appears to be a suitable technique for quality control in the coffee industry, and for fundamental investigation on the mechanisms involved in the roasting process (AU) s