Stability of the mixture of technetium-99m human serum albumin and lidocaine hydrochloride for clinical application.

Abstract

AIM:

To evaluate the stability of the mixture of technetium-99m (99mTc) human serum albumin (HSA) with the local anesthetic lidocaine hydrochloride.

MATERIALS AND METHODS:

We assessed three preparations of the radiotracer, 99mTc-HSA, filtered 99mTc-HSA, and a mixture of 99mTc-HSA with lidocaine hydrochloride and then filtered. Time sequence evaluation was performed on all the specimens (n= 10) at 0, 30, 60, 90, 120, 150, and 180 min after preparation. Measurements of radiochemical purity as labeling stability and pH value change were conducted for each group of specimens.

RESULTS:

We found no definite difference in the stability before and after the filtering procedure for 99mTc-HSA. However, we showed a decline of stability in the mixture of 99mTc-HSA with lidocaine. The filtered specimens showed a relatively higher pH value, towards a more neutral status, as compared with the unfiltered specimens.

CONCLUSION:

Though pain relief for the patient receiving sentinel lymph node mapping is important, a preparation of a mixture of 99mTc-HSA and lidocaine may cause radiolabeling instability. Furthermore, compared with the filtered 99mTc-sulfur colloid, a filtering procedure does not change the labeling stability of the 99mTc-HSA. On the contrary, the filtered preparation was neutralized closer to the physiologic condition. For lymphoscintigraphic studies,our results suggested that pretreatment with local anesthesia followed by subdermal injection of a filtered 99mTc-HSA rather than a pre-mixture with lidocaine is appropriate for clinical application.

• Authors: Yuh-Feng Wang, Mei-Hua Chuang, Thau-Ming Cham, Mei-Ing Chung
• Journal: Nuclear medicine communications (Nucl Med Commun) Vol. 30 Issue 7 Pg. 494-7 (Jul 2009) ISSN: 1473-5628 [Electronic] England
• PMID: 19430321 (Publication Type: Journal Article, Research Support, Non-U.S. Gov't)

Chemical References

• Anesthetics, Local
• Technetium Tc 99m Aggregated Albumin
• Lidocaine

Topics

• Anesthetics, Local (chemistry)
• Drug Stability
• Humans
• Hydrogen-Ion Concentration
• Lidocaine (chemistry)
• Staining and Labeling
• Technetium Tc 99m Aggregated Albumin (chemistry)
• Time Factors