[Stabilization of 99m Tc-HMPAO with methylene blue: its use in leukocyte labelling)].
A method to stabilize the 99mTc-HMPAO obtained from Ceretec(R) saline fractions using methylene blue is described. The mean radiochemical purity two hours after the stabilized 99mTc-HMPAO preparation was 92.5% (SD 1.8%), the pH ranged from 7.0 to 7.6 and the osmolality ranged from 305 to 309 mOsm/kg. These features made the stabilized 99mTc-HMPAO suitable for leukocyte labelling. In order to evaluate this method, we performed the labelling of two identical leukocyte samples withdrawn from 10 blood donors. The first sample was labeled using 99mTc-HMPAO non-stabilized and the second one was labelled using 99mTc-HMPAO stabilized 2 hours before with methylene blue. The mean labelling efficiencies we obtained were 70.9% (SD 6.9%) and 66.1% (SD 4.2%) respectively. With the conditions described using the 99mTc-HMPAO stabilized with methylene blue, we had no drawbacks from the stabilizing blue colour and we did not found changes in the cellular viability.
Unidad de Radiofarmacia - Servicio de Medicina Nuclear, Ciutat Sanitària i Universitària de Bellvitge, L'Hospitalet de Llobregat, Barcelona, 08907, España.
V
V
García Seguí
M
M
Roca Engroñat
F
F
Armero Muñoz
F
F
Iglesias Allende
V
V
Gomes Barreto de Mélo
J
J
Martin-Comín
D002470:Cell Survival; D002626:Chemistry, Pharmaceutical; D004355:Drug Stability; D006801:Humans; D006863:Hydrogen-Ion Concentration; D007553:Isotope Labeling / Q000379:methods*; D007962:Leukocytes; D008751:Methylene Blue / Q000494:pharmacology*; D009994:Osmolar Concentration; D019690:Technetium Tc 99m Exametazime / Q000737:chemistry*
D019690:Technetium Tc 99m Exametazime; D008751:Methylene Blue