Determination of Ferric Oxide in Calamine Powder by FAAS / 中国药师

Objective:To determine the content of ferric oxide in calamine powder. Methods:Flame atomic absorption spectrom-etry ( FAAS) was used to determine the content of ferric oxide. The determination results were compared with those of the titration method. Results:There was a good linear relationship between the absorbance and the concentration of iron within the range of 0. 5-4μg·ml-1 , the relative standard deviation of the repeatability test was 1. 2%, the average recoveries were 100. 4% and 99. 4%, the limit of quantitation and detection was 0. 081 μg·ml-1 and 0. 024 μg·ml-1 , respectively. Conclusion:The method of FAAS is ac-curate and quick with good specificity and high sensitivity, which can be used for the determination of ferric oxide in calamine powder.

Determination of Five Heavy Metals and Harmful Elements in Freeze-dried Rehmannia from Different Habitats / 中国药师

Objective:To analyze the content of Pb, Cd, Cu, As and Hg in freeze-dried Rehmannia from different habitats by FAAS and double channels AFS. Methods:The contents of Pb,Cd and Cu in Rehmannia from different habitats were directly deter-mined by FAAS, while the contents of As and Hg were determined by double channels AFS after pretreated with HNO3-HClO4 . Re-sults:It was shown that each element had good linear relationship with the correlation coefficient above 0. 997 4. The average recovery was 97. 88%-100. 90% with RSD of 0. 019% -4. 20% (n=6). Meanwhile, the concentrations of 5 harmful elements and heavy met-als in 4 batches of 10 samples were higher than the limits described in Chinese pharmacopoeia. Conclusion:The results measured by the method are considered to be accurate, quick and easy to be operated. It can be used to determine heavy metals and harmful ele-ments in freeze-dried Rehmannia from different habitats.

Determinação sérica de lítio: comparação das metodologias de espectrometria de emissão e de absorção atômica / Determination of serum lithium: comparison between atomic emission and absorption spectrometry methods

Introduction: The therapeutic monitoring of lithium, through concentration measurements, is important for individual dose adjustment, as a marker of treatment adherence and to prevent poisoning and side effects. Objectives: Validate and compare two methods - atomic emission and atomic absorption - for the determination of lithium in serum samples. Methodology: Parameters such as specificity, precision, accuracy, limit of detection (LOD) and linearity were considered. The atomic absorption spectrometer was used, operating in either emission or absorption mode. For the quantitative comparison of 30 serum samples from patients with mood disorder treated with lithium, the results were submitted to Student's t-test, F-test and Pearson's correlation. Results: The limit of quantification (LOQ) was established as 0.05 mEq/l of lithium, and calibration curves were constructed in the range of 0.05-2 mEq/l of lithium, using aqueous standards. Sample preparation time was reduced, what is important in medical laboratory. Conclusion: Both methods were considered satisfactory, precise and accurate and can be adopted for lithium quantification. In the comparison of quantitative results in lithium-treated patients through statistical tests, no significant differences were observed. Therefore the methods for lithium quantification by flame atomic absorption spectrometry (FAAS) and flame atomic emission spectrometry (FAES) may be considered similar...

Introdução: A monitorização terapêutica por meio da determinação sérica de lítio é importante para proporcionar o ajuste individual da dose, como marcador de adesão e para prevenir intoxicações. Objetivos: Validar e comparar duas metodologias, a de emissão e a de absorção atômicas, para determinação de lítio em amostras de soro. Metodologia: Foram determinados parâmetros de especificidade, precisão, exatidão, limite de detecção e linearidade a fim de validar as metodologias para determinação de lítio. Foi utilizado espectrômetro de absorção atômica, funcionando no modo de emissão ou de absorção. Para comparação das metodologias foram utilizados os testes estatísticos (teste t de Student, o teste F e a correlação de Pearson) nos resultados quantitativos de 30 amostras de soro sanguíneo de pacientes que faziam uso terapêutico de lítio para o controle do transtorno de humor bipolar (THB). Resultados: Foram estabelecidos um limite de quantificação de 0,05 mEq/l de lítio e curvas de calibração de 0,05 a 2 mEq/l de lítio, construídas utilizando padrões aquosos, com redução no tempo de preparo das amostras, principalmente para ser utilizado em laboratório de análises clínicas. Conclusão: Os dois métodos foram considerados satisfatórios, precisos e exatos e podem ser adotados para a quantificação do lítio. Na comparação dos dois métodos por testes estatísticos em amostras de pacientes tratados com o fármaco, não foram observadas diferenças significativas entre os resultados encontrados. Desta forma, os métodos para quantificação do lítio por espectrometria de absorção atômica em chama (FAAS) e espectrometria de emissão atômica em chama (FAES) podem ser considerados semelhantes...

Determinación de macro elementos en exudado de hojas de zábila (Aloe vera (L.) Burm. f.) / Macroelements determination in zabila leaves exudate (Aloe vera (L.) Burm. f.)

El Aloe vera (L.) Burm. f. (zábila) es una planta utilizada por sus propiedades medicinales, la parte utilizada de esta planta es su hoja, de ésta se extraen dos componentes: los cristales y el exudado. En esta investigación se estudió la concentración de macro elementos presentes en el exuda-do de hojas de zábila, a saber: sodio (Na), calcio (Ca), magnesio (Mg) y potasio (k) por espectrometría de absorción atómica en llama (FAAS). Las plantas estudiadas fueron cultivadas en la ciudad de Coro, estado Falcón. Las muestras compuestas de exudado se recolectaron en hojas ubi-cadas en las posiciones bajas, medias y superiores de las plantas. Luego se secaron por liofilización, y se mineralizaron: 0.25 g de muestra de exudado se sometieron a digestión ácida, con 1:2 HNO3 concentrado y H2O2 en plancha de calentamiento. Se utilizó material certificado NIST 1572, USA: Hojas de plantas cítricas, para evaluar la exactitud del método, no encontrándose diferencias estadísticamente significativas (p <0.05) entre los valores del material de referencia con los valores obtenidos con el método aplicado en esta investigación. El promedio de la desviación estándar relativa (RSD) fue de 1.41%, lo que certifica la precisión del método empleado. Las concentraciones de los macro elementos encontradas fueron: Na: 0.24 ± 0,03% p/p, k: 0.69 ± 0,13% p/p, Ca: 0.07 ± 0,01% p/p y Mg: 0.01 ± 0,00% p/p. El método empleado para determinar la concentración de Na, Ca, Mg y k en muestras de exudado de zábila por FAAS fue exacto, preciso y libre de interferencias.

The objective of this work was to determine the metals in Aloe vera (L.) Burm. f. (zabila). Theses metals are necessary in the human organism; namely: Na, k, Ca y Mg. It was digested for 1 hour in a hot plate at 70 ºC 0.25 g of lyo-philized exudate with 1:2 nitric acidic and hydrogen peroxi-de. It was no found significatives statistics differences at 95% of confidence between the standard calibration curve and the aqueous calibration curve, so no matrix effect was observed. The recovery studies was satisfactory, the mean value was 99.77 ± 2%. It was no found significatives statistics differences at 95% of confidence between the certificated values (NBS: Citrics leaves 1572) of studied metals and the values found with the applied methodology. The concentrations of these elements in the real composed samples were: Na: 0.24 ± 0,03% w/w; k: 0.69 ± 0,13% w/w; Ca: 0.07 ± 0,01% w/w; Mg: 0.01 ± 0,00% w/w. The method used to determine the determined elements was exact, pre-cise and free from interferences.

Determinación de microelementos en acíbar de hojas de zábila (Aloe vera (L.) Burm. f.) / Determination of microelements in exudate from leaves of zábila (Aloe vera (L.) Burm. f.)

En esta investigacion se estudio la concentracion de microelementos tales como cobre, zinc, manganeso y hierro en el acibar de hojas de zabila, por espectrometria de absorcion atomica en llama (FAAS); asimismo, la concentracion de cromo por espectrometria de absorcion atomica electrotermica (ETAAS). Las plantas fueron cultivadas en la ciudad de Coro, estado Falcon, Venezuela. Las muestras de aci bar se recolectaron en hojas internas, medias y externas de la planta. Luego, se secaron por liofilizacion y se mineralizaron: 0,25 g de muestra de acibar se sometio a digestion humeda por 1 hora a 70 oC en una plancha de calentamiento, con 1:2 HNO3 y H2O2. No se encontro efecto de matriz, ya que no hubo diferencia estadisticamente significativa entre la pendiente de la curva de calibracion acuosa y la obtenida por adicion de estandar. El estudio de recuperacion fue satisfactorio, siendo el valor promedio 97,02 ± 4,65%. La exactitud del metodo se evaluo utilizando material certificado de la National Bureau of Standards (NBS) 1572, no encontrandose diferencias estadisticamente significativas entre los valores de los metales contenidos en el material de referencia con los valores obtenidos con el metodo aplicado en esta investigacion. Con relacion a la precision, el promedio de la desviacion estandar relativa fue de 1,26%, lo que certifica la precision del metodo empleado. Las concentraciones de metales (media poblacional ± intervalos de confianza) encontradas fueron las siguientes: Cu: 1.604 ± 0.296 mg/g, zn: 6.381 ± 0.974 mg/g, Fe: 14.609 ±3.161 mg/g, Mn: 5.058 ± 0.307 mg/g y Cr: 13.174 ± 3.046 mg/g. El metodo empleado fue exacto, preciso y libre de interferencias.

In this investigation was studied the concentration of microelements such as: Cu, zn, Fe and Mn in Aloe vera (L.) Burm. f. leaves exudates by atomic absorption spectrometry (FAAS), also the Cr concentration was determined by electrothermal atomic absorption spectrometry (ETAAS). The plants were cultivated in Coro city, Falcon state, Venezuela. The exudates samples were recollected from internal external and intermediate leaves of the plant. It was digested for 1 hour in a hot plate at 70 oC 0.25g of lyophilized exudates with 1:2 nitric acidic and hydrogen peroxide. It was no found significatives statistics difference at 95% of confidence between the standard calibration curve and the aqueous calibration curve, so no matrix effect was observed. The recovery studies was satisfactory, the mean value was 97.02 ± 4.65%. It was no found significatives statistics differences at 95% of confidence between the certificated values from The National Bureau of Standards (NBS) 1572 of studied metals and the values found with the applied methodology, so the method applied was accurate. The precision of the method was 1.26%. The concentrations of these elements in the real samples were: Cu: 1,604 ± 0,296 mg/g; zn: 6,381 ± 0,974 mg/g; Fe: 14,609 ± 3,161 mg/g; Mn: 5,058 ± 0,307 mg/g and Cr: 13,174 ± 3,046 mg/g. The method used to determine these elements was exact, precise and free from interferences.

Quantificação laboratorial de cobre sérico por espectrofotometria Vis comparável à espectrometria de absorção atômica com chama / Laboratorial quantification of serum copper by Vis spectrophotometry in comparison to flame atomic absorption spectrometry

INTRODUÇÃO: O cobre é um nutriente essencial para os humanos, e a manutenção dos seus níveis é importante, uma vez que seu metabolismo está envolvido com estresse oxidativo e patologias, como a Doença de Wilson. Neste trabalho, um método de espectrofotometria visível (espectrofotometria Vis) foi validado, aplicado em indivíduos jovens e comparado com espectrometria de absorção atômica com chama (EAA-chama). MÉTODOS: Concentrações séricas de cobre foram medidas por EAA-chama e por espectrofotometria Vis, através da reação de cobre com batocuproína, l = 484 nm. Curvas analíticas em solução aquosa e com adição de padrão foram efetuadas para verificar linearidade, recuperação e precisão do método espectrofotométrico. Amostras de sangue de 12 indivíduos (média de idade 22 anos) foram analisadas por ambos os métodos e comparadas entre si. Os resultados foram expressos em média ± desvio-padrão. RESULTADOS: As curvas com adição de padrão e aquosa (n = 5) apresentaram coeficientes de regressão superiores a 0,99 e de variação inter e intradia inferiores a 15 por cento. Os valores de cobre sérico encontrados para o método espectrofotométrico foram 1,17 ± 0,39 e 0,73 ± 0,14 mg/l para mulheres e homens, respectivamente. Para EAA-chama foram encontrados 1,13 ± 0,43 e 0,59 ± 0,13 mg/l para mulheres e homens, respectivamente. Os resultados mostraram correlação de Pearson significativa (r = 0,946; p < 0,05). Os níveis séricos de cobre foram significativamente maiores em mulheres do que em homens (p < 0,05). CONCLUSÃO: O método espectrofotométrico visível demonstrou ser linear, reprodutível e aplicável, oferecendo uma alternativa confiável à quantificação de cobre por EAA-chama. Além disso, é uma técnica simples, rápida e barata, que pode ser utilizada na rotina laboratorial clínica.

BACKGROUND: Copper is an essential nutrient for humans and maintenance of its adequate levels is important, since its metabolism is involved with oxidative stress and patolologies, such as Wilson's disease. In this work, a visible spectrophotometric method was validated, applied in young subjects and compared to flame atomic absorption spectrometry (FAAS) in serum copper levels determination. METHODS: Serum copper concentrations were measured by FAAS and by spectrophotometry, through copper reaction with bathocuproine, l = 484 nm. Aqueous curves and spiked serum curves were realized to verify linearity, recovery and precision of the visible spectrophotometric method. Blood samples from 12 subjects (mean 22 years) were analyzed in both methodologies and compared to each other. The results were expressed by mean ± standard deviation. RESULTS: Spiked serum and aqueous curves (n = 5) showed coefficient of regression superior to 0.99 and inter and intra-day coefficient of variation lower than 15 percent. The serum copper values found to Vis spectrophotometric method were 1.17 ± 0.39 and 0.73 ± 0.14 mg/l to women and men, respectively. To FAAS 1.13 ± 0.43 and 0.59 ± 0.13 mg/l were found to women and men, respectively. Both results showed a significant Pearson correlation (r = 0.946; p < 0.05). Besides, serum copper levels were significantly higher in women than in men (p < 0.05). CONCLUSION: The Vis spectrophotometric method demonstrated to be linear, reproducible and applied, offering a reliable alternative to FAAS copper quantification. Moreover, Vis spectrophotometry is a simple, quickly and not expensive technique, and it could be widely used as routine in clinical laboratory.