Aplicação da Cromatografia Líquida de Alta Performance Como Método Preparativo Para a Dosagem de Esteróides Hormonais Por RIE: Dosagens de 17OH-Progesterona e Diidrotestosterona

Abstract

Preparative HPLC for Steroid Measurements: Determinations of 170H-Progesterone and Dihydrotestosterone. Measurement of steroid hormones has undergone a significant technical evolution so that steroids with greater clinical interest are, nowadays, measured with methods that are simple, fast and prone to automation. Nevertheless, a compromise is made in detriment of accuracy, which is more evident with steroids with lower concentration and more potential interferents, as 17-hydroxyprogesterone (17OHP), dihydrotestosterone (DHT), and others. In such cases, a robust and versatile preparative process is of utmost importance to warrant results with the highest degree of accuracy. In this paper we present the results obtained with the use of a preparative process based on high-pressure chromatography (HPLC) for the measurement of 17OHP and DHT, as compared with a process based on celite column chromatography. The antibodies used in the radioimmunoassays have similar specificity to those previously described for these kinds of assays. Samples were initially extracted in ethyl ether and then submitted to HPLC. Routine samples (57 for 17OHP and 84 for DHT) were measured in parallel with both methods. The differences between results were not statistically significant, and the correlation indexes were high (R= 0.95 and 0.97). Our results confirm that systems

Simultaneous quantitation of seven endogenous C-21 adrenal steroids by liquid chromatography tandem mass spectrometry in human serum

“…For 17-hydroxyprogesterone, 86 samples were compared with an in-house developed method based on liquid-liquid extraction followed by HPLC purification and detection by RIA [21]. For 11-desoxycortisol, 51 samples were analyzed by the present method and by an in-house RIA method with previous liquid-liquid extraction and Celite ® chromatography [22].…”

Aplicação da cromatografia líquida de alta eficiência para quantificação direta da 17

“…Os principais problemas dos ensaios de hormônios esteróides por essa técnica estão relacionados à grande semelhança estrutural que existe entre eles e à dificuldade de obtenção de anticorpos específicos associados à ampla faixa de concentração em que podem ser encontrados (Vieira et al, 1999). A cromatografia líqui-da tem sido empregada para a separação da 17OHP com posterior quantificação por RIA (Wong et al, 1992;Vieira, Nakamura, Noguti, 2002;Tonetto-Fernandes et al, 2003) bem como para quantificação direta (Saisho, Shimozawa, Yata, 1990;Wei et al, 1990;Gudmundsson et al, 1999). A espectrometria de massas, associada à cromatografia gasosa (GC-MS) ou à cromatografia líquida (LC-MS), também tem sido empregada na determinação desse esteróide (Lai et al, 2001(Lai et al, , 2002.…”