Determinação espectrofotométrica simultânea de paracetamol e ibuprofeno em formulações farmacêuticas usando calibração multivariada

A simple method was proposed for determination of paracetamol and ibuprofen in tablets, based on UV measurements and partial least squares. The procedure was performed at pH 10.5, in the concentration ranges 3.00-15.00 µg ml-1 (paracetamol) and 2.40-12.00 µg ml-1 (ibuprofen). The model was able to predict paracetamol and ibuprofen in synthetic mixtures with root mean squares errors of prediction of 0.12 and 0.17 µg ml-1, respectively. Figures of merit (sensitivity, limit of detection and precision) were also estimated. The results achieved for the determination of these drugs in pharmaceutical formulations were in agreement with label claims and verified by HPLC.

Desenvolvimento de método analítico por CLAE em comprimidos de Benznidazol para a Doença de Chagas

The analytical method of high performance liquid chromatography (HPLC) for the assay of benznidazole in tablets was developed and validated following the requirements of regulatory agencies. The method used as mobile phase acetonitrile:wather 1:1, a C18 column of 12.5 cm length x 4 mm id, 5 mm particles and lambda=316 nm. The statistical analysis of the results demonstrated that the method satisfies all parameters so as to be considered a safe and efficient analytical alternative of low cost for laboratory routine.

Validação de método por cromatografia líquida de alta eficiência para determinação da lamivudina e zidovudina em comprimidos

An HPLC method was validated to assay lamivudine and zidovudine combined in tablets. The chromatographic separation was carried out using methanol and acetate buffer pH 6.5 (50:50 v/v) and a RP-18 column, as mobile and stationary phase, respectively. The UV detection was at 270 nm. The method was linear in the range of 24 - 36 µg/mL (lamivudine) and 48 - 72 µg/mL (zidovudine). The recovery (accuracy) ranged from 101.35% to 103.04% and the precision (repeatability and intermediate precision) was less than 2%. The method can be also applied to the quantification of these drugs in the dissolution test of tablets containing both drugs.

Periodismo y dispositivos móviles de lecto-escritura. Introducción al diseño de contenidos para tabletas

El lanzamiento de las tabletas, especialmente la iPad de Apple en 2010, abrió la competencia entre las compañías de comunicación en el sentido de hacer disponible el contenido para este entorno de medios emergentes. La fuga de lectores de periódicos impresos y la consecuente caída en las ganancias por publicidad, forzó a las compañías periodísticas a que buscaran los otros medios de mantener sus negocios. La diversificación de productos y la penetración de los periódicos en dispositivos móviles constituyen un escenario prometedor para el medio. El vertiginoso volumen de ventas de las tabletas indica que en 2012 serán comercializadas más de 140 millones de unidades en el mundo. El diseño de los periódicos en tabletas está íntimamente ligado al diseño de la versión impresa por la fuerza de su metáfora. El desafío es encontrar un diseño de páginas propio, aprovechando el potencial multimedia sin interferir negativamente en la legibilidad y en el carácter intrínseco de informar.

Aaltovoimalaitteen toimintaperiaatteen analysointi

Diplomityö tehtiin Wello Oy:n toimeksiannosta. Wello Oy on vesi- ja tuulivoimaratkaisuihin keskittynyt yritys, joka kehittää aaltovoimalaitekonseptia. Työssä selvitettiin aaltovoimaan liittyviä ilmiöitä ja aaltovoimalaitteen mekaanista konseptia ja tehtiin arvio niiden tehokkuudesta. Työssä käytettiin kaupallisia simulointityökaluja kuten monikappaledynamiikan simulointiohjelmaa MSC.ADAMS R3:a ja yleistä matematiikka ohjelmaa Matlab Simulink:ia. Simulointimallia käytettiin arvioimaan laitteen yleistä käyttäytymistä. Lisäksi laitteen analyyttisiä malleja käytettiin laitteen toimintaperiaatteen selvitykseen. Simulointia käytettiin kelluvan laitteen mekanismin tutkimukseen. Tuloksiin pohjautuen laitteelle määriteltiin teoreettiset maksimiteho rajat ja rajoitteet, jotka vaikuttavat laitteen tehokkuuteen.

Nivel de calidad de los medicamentos elaborados por los alumnos en el laboratorio de prácticas y de su control como producto acabado por parte de los mismos alumnos

Una de las prácticas de laboratorio de Tecnología Farmacéutica requiere la elaboración de comprimidos en la asignatura de Farmacia Galénica II siguiendo el mismo flujo de fabricación al empleado en la industria farmacéutica (pesada, tamización, mezclado, amasado, granulación, secado, mezclado y compresión). Estos comprimidos se analizan en la asignatura de Farmacia Galénica III (entre 6 y 12 meses más tarde) por los mismos alumnos según las directrices de la Real Farmacopea Española.En el trabajo se exponen gráficamente los resultados hallados y se comentan los principales puntos de mejora ya que el producto elaborado no es conforme en la mayoría de los casos (sólo alrededor del 50% de los productos elaborados por los alumnos podrían ser conformes, aún siendo un proceso validado). Realmente, la experiencia de los operadores es el punto más crítico que influye en los resultados de estos lotes de comprimidos, sobre todo en el laboratorio analítico. Esta hipótesis ha sido confirmada en lotes analizados por el personal cualificado del departamento de control de calidad del Servei de Desenvolupament del Medicament de la Facultat de Farmàcia de la Universitat de Barcelona, ya que en todos los casos los resultados obtenidos fueron más exactos, repetitivos y cercanos a los teóricos.

Fluxos de óxido nitroso na interface ar-mar na Baía de Guanabara

In Surface water concentrations of N2O were measured at 37 stations in Guanabara Bay and fluxes estimated across the air-sea interface. Concentrations averaged 8.2 ± 2.2 nmol L-1 and 90% of the stations showed supersaturation averaging 33%. N2O fluxes were estimated using a two-film model which is given by the product of the concentration difference across the film and the gas transfer coefficient (k w). Two parametrizations of k w were used which provided average fluxes of 0.3 and 3.0 µg N m-2 h-1. Flux measurements using floating chambers (not reported here) seem to agree with the upper limit of these estimates.

Determinação de 3,4-metilenodioximetanfetamina (MDMA) em comprimidos de Ecstasy por cromatografia líquida de alta eficiência com detecção por fluorescência (CLAE-DF)

This paper describes the development and validation of simple and selective analytical method for determination of 3.4-methylenedioxymethamphetamine (MDMA) in Ecstasy tablets, using high performance liquid chromatography with fluorescence detection. Analysis was performed in a reversed phase column (LiChrospher 100 C18, 150 x 4.6 mm, 5 µm), isocratic elution with phosphate buffer 25 mmol/L pH 3.0 and acetonitrile (95:5, v/v). The method presents adequate linearity, selectivity, precision and accuracy. MDMA concentration in analyzed tablets showed a remarkable variability (from 8.5 to 59.5 mg/tablet) although the tablet weights were uniform, indicating poor manufacturing control thus imposing additional health risks to the users.

Extração e purificação de fármacos anti-inflamatórios não esteroidais ciclo-oxigenase-2 seletivos

Celecoxib (CB) and lumiracoxib (LM) are potent COX-2 inhibitors widely marketed for the treatment of rheumatoid arthritis and osteoarthritis. Nevertheless, it is difficult to obtain because it are protected under patents. The aim of this work was to develop an extraction method of drugs, CB and LM, in order to obtain the drug with a purity degree appropriated for use in research projects. The developed method showed to be effective of both drugs, becoming interesting due to its low cost, easy and speed of execution, application to different dosage forms (capsules and tablets) and drugs with different physicochemical properties.

Development of a flotation method for preconcentration-separation of trace amounts of some metal ions in plant tissues prior to their FAAS determinations

An efficient flotation method based on the combination of flame atomic absorption spectrometry (FAAS) and separation and preconcentration step for determination of Cr3+, Cu 2+, Co2+, Ni2+, Zn2+, Cd 2+, Fe3+ and Pb2+ ions in various real samples by the possibility of applying bis(2-hydroxyacetophenone)-1,4-butanediimine (BHABDI) as a new collector was studied. The influence of pH, amount of BHABDI as collector, sample matrix, type and amount of eluting agent, type and amount of surfactant as floating agent, ionic strength and air flow rates i.e. variables affecting the efficiency of the extraction system was evaluated. It is ascertained that metal ions such as iron can be separated simultaneously from matrix in the presence of 0.012 mM ligand, 0.025% (w/v) of CTAB to a test sample of 750 mL at pH 6.5. These ions can be eluted quantitatively with 6 mL of 1.0 mol L-1 HNO3 in methanol which lead to the enrichment factor of 125. The detection limits for analyte ions were in the range of 1.3-2.4 ng mL-1. The method has been successfully applied for determination of trace amounts of ions in various real samples.

Determinação de olanzapina em formulações farmacêuticas por espectrofotometria: desenvolvimento e validação

Spectrophotometric methods of zero order, first and second derived order had been developed for olanzapine determination in tablets using ethanol and isopropanol as solvent. The two solvents revealed to be adequate. For the three methods the calibration curve coefficient of correlation had been greater than 0.9998 with limit of detection varying from 0.068 to 0.190 mg L-1, in ethanol, and 0.026 to 0.205 mg L-1, in isopropanol. The inter-day precision was inferior to 1.1 and 1.9 mg L-1 for ethanol and isopropanol, respectively. The average recoveries varied from 98 to 101%, in ethanol and 99 to 103% in isopropanol.

Avaliação do desempenho de surfactantes para a solubilização de fases líquidas não aquosas em meio aquoso

The presence of non-aqueous phase liquids (NAPLs) in the subsurface is a threat to public health as well as a serious environmental issue. NAPLs may remain adsorbed or form lenses floating on aquifers causing long-term contaminations. Surfactants may increase NAPLs solubility, enhancing the pump-and-treatment performance. Size, shape, hydration and ionization degree of the micelles define the affinity and the space available for the solubilization of a particular contaminating agent. The tests carried out at laboratory scale, taking into account the NAPL to be removed and the medium characteristics were useful to select surfactants and evaluate their efficiency as NAPLs solubilizers.

Flow injection green method for the quantitative analysis of ketoconazole in pharmaceutical preparations

A flow injection method for the quantitative analysis of ketoconazole in tablets, based on the reaction with iron (III) ions, is presented. Ketoconazole forms a red complex with iron ions in an acid medium, with maximum absorbance at 495 nm. The detection limit was estimated to be 1×10--4 mol L-1; the quantitation limit is about 3×10--4 mol L-1 and approximately 30 determinations can be performed in an hour. The results were compared with those obtained with a reference HPLC method. Statistical comparisons were done using the Student's t procedure and the F test. Complete agreement was found at the 0.95 significance level between the proposed flow injection and the HPLC procedures. The two methods present similar precision, i.e., for HPLC the mean relative standard deviation was ca. 1.2% and for FIA ca. 1.6%.

Identificação química da clorofenilpiperazina (CPP) em comprimidos apreendidos

Designer drug is a term used to describe psychoactive drugs of abuse which are usually synthesized by modifying the molecular structures of existing drugs of abuse. The term gained widespread popularity when MDMA (ecstasy) experienced a popularity boom in the mid 1980´s. In Brazil, designer drugs seizures have increased in the last few years, and actually tablets with unknown psychoactive compounds began to be forwarded to the Forensic Laboratories. This work describes the analytical assays that were performed to identify the chlorophenylpiperazine, a psychoactive substance first time identified in seized tablets in Sao Paulo state.

Development of a simple, rapid and validated spectrophotometric method for nitazoxanide in pharmaceutical formulations and comparison with HPLC

A rapid, economical, reproducible, and simple direct spectrophotometric method was developed and validated for the assay of nitazoxanide in pharmaceutical formulations. Nitazoxanide concentration was estimated in water at 345 nm and pH 4.5. The method was suitable and validated for specificity, linearity, precision, and accuracy. There was no interference of the excipients in the determination of the active pharmaceutical ingredient. The proposed method was successfully applied in the determination of nitazoxanide in coated tablets and in powders for oral suspension. This method was compared to a previously developed and validated method for liquid chromatography to the same drug. There was no significative difference between these methods for nitazoxanide quantitation.