Evaluation of radiochemical purity and stability of 99mTc-HSA complex in fluid for peritoneal dialysis in vitro

Human serum albumin (HSA) labeled with 131I or 99mTc was adopted in isotopic diagnostics for evaluation of volume and dynamics of vascular system. Because of high doses absorbed by patient's body due to long half-life period and high energy of 131I application of 99mTc (low energy, short half-life) to HSA labelling would be useful. Condition for applying of 99mTc-HSA in monitoring of peritoneal dialysis kinetics is complex stability during four-hour period in peritoneal dialysis conditions. Evaluation of stability of 99mTc-HSA complex in period from 30 minutes to 4 hours after complex preparation was done by means of paper radiochromatography and column chromatography. Additionally, separation of the complex after one- and four-hour incubations with solutions for peritoneal dialysis was done. The studies carried out proved stability of the complex during 4-hour period after preparation and incubation with solutions for peritoneal dialysis. 99mTc-HSA complex content was above 98% at all time intervals. The result obtained point out possibility of replacing of albumin labeled with 131I by albumin labeled with 99mTc