An alternative for radiotracer technique in Cuba, is the use of sodium pertechnate ( ) eluted from / generator. This radioisotope generator is produced by the Cuban Center of Isotopes (CENTIS). Taking into account that solvent extraction is an usual procedure to separate from the fission products, this technique was used to get a radiotracer in organic phase from the eluted , using 30% TBP-16% TOA/ n-dodecane and 30% TBP-16% TOA/ ciclohexane as solvents. On the other hand, MEK is used as solvent in the so called / extraction radioisotope generator. Consequently, it was also evaluated. In this paper, the influence on the extraction degree, of the volumetric ratio between organic and aqueous phases, the time of phase shaking and the time elapsed between shaking-end and phase separation were studied. Furthermore, in the case of MEK, the influence of NaOH concentration in the aqueous phase was considered. For the extraction using 30% TBP-16% TOA/ciclohexane and 30% TBP-16% TOA/n-dodecane, the influence of pH was also studied. The extraction degree of eluted from generator using MEK, as well as 30% TBP-16% TOA in n-dodecane or ciclohexane, in adequate conditions, was higher than 99%, so, any of the tested solvents could be used to get a radiotracer in organic phase.