Journal of Nuclear Medicine Technology, Vol 26, Issue 3 196-199, Copyright © 1998 by Society of Nuclear Medicine
Adsorption of some technetium-99m radiopharmaceuticals onto disposable plastic syringes
BA Jansson, MB Goransson and BN Agren
Hospital Pharmacy, Huddinge University Hospital, Sweden.
OBJECTIVE: The purpose of this study was to determine the adsorption
behavior of some widely used, commercially available 99mTc
radiopharmaceuticals onto different types of plastic syringes. METHODS:
Kits were reconstituted with 99mTc-pertechnetate diluted with 0.9% saline
to produce maximum radioactive concentrations, as stated by the
manufacturers. Aliquots of the solutions were transferred to four different
brands of 2-ml syringes. The activity in the syringes was measured before
and after injections or simulated injections. The amount adsorbed to the
plastic syringe barrel and plunger before and after washout also was
measured at different time intervals. Comparisons between products from
different manufacturers were made for 99mTc succimer (DMSA) and 99mTc
macroaggregated albumin (MAA). RESULTS: Some 99mTC preparations undergo
significant adsorption to plastic syringes. Adsorption differs considerably
between products from different manufacturers. There was significantly
higher residual activity in some types of syringes. In some cases the
residual was as high as 40%-50% of the initial activity, and most of the
adsorption occurred within 15 min of filling the syringe. CONCLUSION: The
data suggest that the extent of adsorption depends on pharmaceutical
excipients in the kits and/or the type of syringe used. When inappropriate
syringes are used, the reduction in the administered activity may result in
poor-quality images. Therefore, the compatibility between
radiopharmaceutical and syringe should be investigated under normal
conditions of preparation and use every time a new brand of syringe or a
new radiopharmaceutical comes into use in diagnostic nuclear medicine.
