RESUMEN
Prostate Specific Membrane Antigen (PSMA) is a highly relevant target in nuclear medicine due to its overexpression in prostate cancer. The 68Ga/177Lu-PSMA-1 combination is a theranostic agent for the detection and treatment of tumors overexpressing the PSMA target. Specifically, 177Lu-PSMA-1 is used in the treatment of castration-resistant prostate cancer that is ineffective or intolerant to the latest generation of chemotherapy and/or hormone therapy. This radiopharmaceutical is manufactured in a radiopharmaceutical synthesizing unit and must pass a quality control where the radiochemical purity (RCP) is assessed prior to release of the batch. RCP evaluation is performed by high-performance liquid chromatography (HPLC) and thin-layer chromatography (TLC). Since there is no monograph for 177Lu-PSMA-1 in the European Pharmacopoeia, we validate the analytical methods according to the EANM recommendations adapted from ICH Q2. Specificity, linearity, accuracy, precision, intermediate precision, limit of quantification (LOQ) and robustness were described for HPLC and TLC in this study. The results obtained demonstrated the robustness and reliability of the HPLC and TLC analytical methods for the evaluation of the RCP of 177Lu-PSMA-1.
RESUMEN
RESUMEN Se desarrolló y validó un método por cromatografía gaseosa para la cuantificación simultánea de mentol (MT), salicilato de metilo (SM), timol (TM) y ácido benzoico (AB) en una solución antiséptica bucal. Se utilizó una columna DB-WAX y dietilenglicol como estándar interno. Se determinó la linealidad en un intervalo de concentraciones de 64,00 a 96,00 µg/mL (MT), 80,00 a 120,00 µg/mL (SM), 96,00 a 144,00 µg/mL (TM) y 48,00 a 72,00 µg/mL (AB), obteniendo coeficientes de correlación superiores a 0,999, y coeficientes de variación de los factores de respuestas de 1,18, 1,95, 3,52 y 1,48%, respectivamente. Se establecieron límites de detección de 0,51; 1,14; 3,34 y 1,402 ng/mL para el MT, SM, TM y AB, respectivamente, mientras los límites de cuantificación fueron de 1,45, 3, 43, 9, 73 y 4, 36 ng/mL en cada caso. Los porcentajes de recuperación fueron de 100,03, 99, 31, 99, 92 y 100,12; con coeficientes de variación de 0,42, 0,79, 0,66 y 0,76% para cada caso. El método fue lineal, exacto, preciso y selectivo para la determinación de los analitos en el control de calidad.
SUMMARY A method was developed and validated by gas chromatography for the simultaneous quantification of menthol (MT), methyl salicylate (SM), thymol (TM) and benzoic acid (AB) in an oral antiseptic solution. A DB-WAX column and diethylene glycol was used as internal standard. Linearity was determined in a concentration range of 64.00 to 96.00 µg/mL (MT), 80.00 to 120.00 µg/mL (SM), 96.00 to 144.00 µg/mL (TM) and 48.00 to 72.00 µg/mL (AB) achieving correlation coefficients greater than 0.999, and coefficients of variation of the response factors of 1.18, 1.95, 3.52 and 1.48%, respectively. Detection limits were established: 0.51, 1.14, 3.34 and 1.402 ng/mL for MT, SM, TM, and AB, respectively, while the quantification limits were 1.45, 3.43, 9.73 and 4.36 ng/mL in each case. Recovery percentages were 100.03, 99.31, 99.92 and 100.12; with coefficients of variation of 0.42, 0.79, 0.66 and 0.76% for each case. The method was linear, accurate, precise, and selective for the determination of analytes in quality control.
RESUMEN
La metodología analítica para la cuantificación de warfarina sódica en tabletas de 5 mg fue estandarizada y validada mediante cromatografía líquida de alta eficiencia acoplada a detector de arreglo de diodo (HPLC-DAD). Se usó como fase móvil una mezcla compuesta por MeOH-AcOH-H2O (68:1:32), una columna cromatográfica C8e Phenomenex® de 150 x 4,6 mm y tamaño de partícula de 5 μm. Los resultados analíticos muestran que el método es preciso, exacto y selectivo para este fármaco. La curva de calibración se realizó en un intervalo del 80 al 120%, en una concentración nominal de 0,1mg/mL, demostrando ser lineal con un coeficiente de correlación a r²> 0,990; el porcentaje de recuperación fue de 98,1% ± 1,3, la precisión medida a través de la repetibilidad y la precisión intermedia fue adecuada (%RSD<2). En la prueba de disolución se encontró un porcentaje de 92,3% ± 3.0. Por lo tanto, la metodología desarrollada cumple con las especificaciones establecida por la USP 38/ NF33.
The analytic methodology for the quantification of sodium warfarin tablets of 5 mg was standardized and validated by High Efficiency Liquid Chromatography coupled to Diode Array Detector (HPLC-DAD). A mixture of MeOH-AcOH-H2O (68:1:32) was used like mobil phase, a chromatographic column C8e Phenomenex® of 150x4.6 mm and a particle size of 5 μm. The analytic results show that the method is precise, accurate and selective for this drug. The calibration curve was performed in the range of 80 to 120% at a nominal concentration of 0.1 mg/mL, demonstrating to be linear with a correlation coefficient at r²> 0.990; recovery rate was 98.1% ± 1.3 and the precision measured through repeatability and intermediate accuracy was adequate (% RSD <2). A percent of 92.3% ± 3.0 was found in dissolution test, thus, the methodology developed complies with the specifications established by USP 38/NF33.
RESUMEN
En este trabajo se muestra el desarrollo y la validación de un método analítico para la cuantificación de polifenoles totales con el reactivo de Folin-Ciocalteu (F-C),en procesos de extracción asistida por microondas (MAE), sobre frutos de la especie colombiana Vaccinium meridionale. Los resultados obtenidos en los parámetros selectividad, linealidad, repetibilidad y exactitud muestran que la metodología propuesta es confiable para evaluar el efecto de las condiciones de extracción sobre la cantidad de polifenoles removidos.
In this work, we show the development and validation of an analytical method for quantification of total polyphenols with Folin-Ciocalteu reagent (F-C) in microwave-assisted extraction processes for Colombian species Vaccinium meridionale. Experimental results of selectivity, linearity, repeatability and accuracy evidence that the methodology proposed is reliable to evaluate the effect of the extraction conditions over the quantity of polyphenols removed.
RESUMEN
Resultados analíticos que näo tenham passado por um processo de validaçäo carecem de qualquer valor. O presente trabalho enfoca etapas algumas vezes negligenciadas em laboratórios de cromatografia e que, no entanto, säo cruciais para a obtençäo de resultados analíticos confiáveis: uso de métodos analíticos validados e como validá-los, confirmaçäo da identidade do composto de interesse, escolha de métodos de quantificaçäo adequados, emprego de amostras de referência e testes de recuperaçäo na rotina de controle de qualidade e participaçäo em testes de proficiência. (AU)
Analytical results that did not go through a validation process lack any value. The resentreview focus into steps for chromatography labs but some times neglected and that are essential forobtaining reliable analytical results: use of validated analytical methods and how to validate analyticalmethods, confirmation of identity of analytes, choice of adequate confirmation methods, routine use ofreference materials and recovery tests for analytical quality control and participation in proficiency tests. (AU)
