Publicaciones científicas

Simple and rapid determination of irinotecan and its metabolite SN-38 in plasma by high-performance liquid-chromatography: application to clinical pharmacokinetic studies

Escoriaza J, Aldaz A, Castellanos C, Calvo E, Giráldez J.
Servicio de Farmacia, Clínica Universitaria de Navarra, Pamplona, Spain.

Revista: Journal of Chromatography

Fecha: 14/04/2000



Irinotecan (CPT-11) is an anticancer agent widely employed in the treatment of colorectal carcinoma. A simple, rapid and sensitive high-performance liquid chromatographic method for the simultaneous determination of CPT-11 and its metabolite SN-38 in plasma, and their preliminary clinical pharmacokinetics are described.

Both deproteinisation of plasma specimens (100 microl) and addition of the internal standard, camptothecin (CPT), are achieved by incorporating to samples 100 microl of a solution of CPT (1 microg/ml) in acetonitrile-1 mM orthophosphoric acid (90:10); 200 microl of this acidified acetonitrile solution, drug-free, is also added to accomplish complete deproteinisation: this procedure reduces sample preparation time to a minimum. After deproteinisation, samples are treated with potassium dihydrogenphosphate (0.1 M) and injected into a Nucleosil C18 (5 microm, 250 x 4.0 mm) column. Mobile phase consists of potassium dihydrogenphosphate (0.1 M)-acetonitrile (67:33), at a flow-rate of 1 ml/min. CPT-11, SN-38 and CPT are detected by fluorescence with excitation wavelength set at 228 nm and emission wavelengths of CPT-11, SN-38 and CPT fixed, respectively, at 450, 543 and 433 nm. The limits of quantitation for CPT-11 and SN-38 are 1.0 and 0.5 ng/ml, respectively. This method shows good precision: the within day relative standard deviation (RSD) for CPT-11 (1-10000 ng/ml) is 5.17% (range 2.15-8.27%) and for SN-38 (0.5-400 ng/ml) is 4.33% (1.32-7.78%); the between-day RSDs for CPT-11 and SN-38, in the previously described ranges, are 6.82% (5.03-10.8%) and 4.94% (2.09-9.30%), respectively. Using this assay, plasma pharmacokinetics of CPT-11, SN-38 and its glucuronidated form, SN-38G, have been determined in one patient receiving 200 mg/m2 of CPT-11 as a 90 min intravenous infusion.

The peak plasma concentration of CPT-11 at the end of the infusion is 3800 ng/ml. Plasma decay is biphasic with a terminal half-life of 11.6 h. The volume of distribution at steady state (Vss) is 203 l/m2, and the total body clearance (Cl) is 14.8 l/h x m2. The maximum concentrations of SN-38 and SN-38G reach 28.9 and 151 ng/ml, respectively.

CITA DEL ARTÍCULO  J Chromatogr B Biomed Sci Appl. 2000 Apr 14;740(2):159-68.



La Clínica es el hospital privado con mayor dotación tecnológica de España, todo en un único centro.

Imagen de un PET, tecnología de vanguardia en la Clínica Universidad de Navarra


Los profesionales de la Clínica realizan una labor continuada de investigación y formación, siempre en beneficio del paciente.

Imagen profesionales de la Clínica Universidad de Navarra


Conozca por qué somos diferentes a otros centros sanitarios. Calidad, rapidez, comodidad y resultados.

Imagen del edificio de la Clínica Universidad de Navarra