[The radiolabeling property of oligonucleotide with 99mTc using NHS-MAG3 as a chelator].
OBJECTIVE
To explore the radiolabeling property of oligonucleotide with 99mTc using NHS-MAG3 as a bifunctional chelator.


METHODS
Three 15-base single-stranded amine-derivitized oligonucleotides, which were antisense(ASON), sense(SON) and mismatched oligonucleotides(MON) of c-myc oncogene mRNA, were coupled with NHS-MAG3 and labeled with 99mTc. The labeled oligonucleotide was purified by Sephadex G25 column chromatogram, then the stability was evaluated. The labeling efficiency of ON-MAG3 was assessed 15 days, 1 month and 2 months after storage at -20 degrees C. The binding rate of 99mTc-ON with plasma protein was measured by the trichloroacetic acid precipitation method.


RESULTS
The average labeling efficiency of 99mTc-ASON, 99mTc-SON and 99mTc-ON was 68.41%, 66.24% and 69.38% respectively, and the radiochemical purity was 96.98%, 95.34% and 94.62%. 99mTc-ON was stable when placed at room temperature or incubated in human serum at 37 degrees C. The labeling efficiency of ON-MAG3 did not significantly change 2 months after storage at -20 degrees C. The plasma protein binding rate of 99mTc-ON was lower than 13%.


CONCLUSIONS
99mTc-ON labeled with NHS-MAG3 method showed superior radiochemical characteristics. The labeling efficiency and radiochemical purity were desirable. The label was stable in serum and the binding with plasma protein was low. 99mTc-ON could be a sort of potential radiopharmaceutical for in vivo applications.
Zhang
Chun
C
Department of Nuclear Medicine, West China Hospital, Sichuan University, Chengdu 610041, China.
Tan
Tian-zhi
TZ
Kuang
An-ren
AR
Li
Yun-chun
YC
Zheng
Jian-guo
JG
Pan
Wei-min
WM
D000818:Animals; D005998:Glycine / Q000031:analogs & derivatives* / Q000737:chemistry / Q000493:pharmacokinetics; D007553:Isotope Labeling / Q000379:methods*; D009841:Oligonucleotides / Q000138:chemical synthesis / Q000737:chemistry* / Q000493:pharmacokinetics; D016376:Oligonucleotides, Antisense / Q000737:chemistry / Q000493:pharmacokinetics; D009842:Oligopeptides / Q000138:chemical synthesis / Q000737:chemistry / Q000493:pharmacokinetics; D015609:Organotechnetium Compounds / Q000138:chemical synthesis / Q000493:pharmacokinetics; D011485:Protein Binding; D011817:Rabbits; D019275:Radiopharmaceuticals / Q000138:chemical synthesis* / Q000493:pharmacokinetics; D011897:Random Allocation; D013388:Succinimides / Q000138:chemical synthesis / Q000737:chemistry* / Q000493:pharmacokinetics; D017263:Technetium Tc 99m Mertiatide / Q000737:chemistry* / Q000493:pharmacokinetics
D009841:Oligonucleotides; D016376:Oligonucleotides, Antisense; D009842:Oligopeptides; D015609:Organotechnetium Compounds; D019275:Radiopharmaceuticals; C118518:S-acetylmercaptoacetyltriserine N-hydroxysuccinimide; D013388:Succinimides; C096273:N-(mercaptoacetyl)glycine; D017263:Technetium Tc 99m Mertiatide; C001426:N-hydroxysuccinimide; D005998:Glycine