Investigation of two new [99mTc]Tc-HEDP preparations that can be expected to give a better lesion-to-normal-bone uptake ratio when used as bone scanning agents.
Two new potential bone scanning agents have been prepared and characterized. One of the agents, Tc(Sn,pH 12)-HEDP, is prepared at pH 12 (and subsequently neutralized). The other agent, Tc(Fe)-HEDP, is prepared by reducing [99mTc]TcO4- by a mixture of Fe(II) and Sn(II). From ion exchange chromatography on Aminex A-28 it appeared that the proportion of early eluting components of the two new agents is larger than that of the usual agent, Tc(Sn,pH 7.4)-HEDP. The stabilities on storage, and in serum, of the three agents appeared to be equally good. The adsorption on tri-calciumphosphate of Tc(Fe)-HEDP and Tc(Sn,pH 7.4)-HEDP was determined at several values of concentrations of Sn(II) and HEDP. Further, the influence of the pH (1-12) during reduction of [99mTc]TcO4- by Sn(II) on the adsorption of the agent on tri-calciumphosphate (at a fixed pH of 7.4) was investigated. It appeared that the adsorption of Tc(Sn,pH 12)-HEDP and Tc(Fe)-HEDP is less than that of Tc(Sn,pH 7.4)-HEDP. It is argued that this result points to a better efficiency in lesion detection of the two new agents, compared to the usual one.
de Ligny
C L
CL
Laboratory for Analytical Chemistry, Utrecht, The Netherlands.
Gelsema
W J
WJ
Hoevelaken
T P
TP
Schuring
J
J
D000327:Adsorption; D001842:Bone and Bones / Q000000981:diagnostic imaging*; D002130:Calcium Phosphates / Q000737:chemistry; D012968:Etidronic Acid / Q000737:chemistry / Q000493:pharmacokinetics*; D006801:Humans; D015609:Organotechnetium Compounds / Q000737:chemistry / Q000493:pharmacokinetics*; D011877:Radionuclide Imaging
D002130:Calcium Phosphates; D015609:Organotechnetium Compounds; C485828:alpha-tricalcium phosphate; C485830:tetracalcium phosphate; C019561:technetium Tc 99m etidronate; C485838:calcium phosphate, monobasic, anhydrous; C020243:calcium phosphate; C485829:calcium phosphate, dibasic, anhydrous; D012968:Etidronic Acid