For the NP radiolabeling
and the preparation of the phospholipid chelator DSPE-DFO, similar
methods were used as previously described.19 (link),65 (link),66 (link)89Zr-oxalate was produced at
Memorial Sloan Kettering Cancer Center (New York) on an EBCO TR19/9
variable-beam energy cyclotron (Ebco Industries Inc., BC, Canada) via the 89Y(p,n)89Zr reaction and
purified in accordance with previously reported methods to yield 89Zr with a specific activity of 195–497 MBq/μg.66 (link) Activity measurements were made using a Capintec
CRC-15R Dose Calibrator (Capintec, Ramsey, NJ). 89Zr-oxalate
was neutralized with aqueous Na2CO3 (1 M), added
to a solution of 0.5 mol % DFO-bearing liposomes or nanoemulsions
in PBS, and stirred at 37 °C for 2 h. The labeled NPs were separated
from free 89Zr using a PD-10 desalting column (GE Healthcare),
with PBS as the eluent and collecting 0.5 mL fractions. The radiochemical
yield was typically >90%. The fractions containing most activity
(∼1.5–2.0
mL) were used for the experiments. These had a radiochemical purity
of >98%, as determined by SEC radio-HPLC analyses performed on
a Shimadzu
system equipped with a Superdex 10/300 SEC column and a A Lablogic
Scan-RAM radio-TLC/HPLC detector. A flow rate of 1 mL/min was used
with demiwater as the eluent.
and the preparation of the phospholipid chelator DSPE-DFO, similar
methods were used as previously described.19 (link),65 (link),66 (link)89Zr-oxalate was produced at
Memorial Sloan Kettering Cancer Center (New York) on an EBCO TR19/9
variable-beam energy cyclotron (Ebco Industries Inc., BC, Canada) via the 89Y(p,n)89Zr reaction and
purified in accordance with previously reported methods to yield 89Zr with a specific activity of 195–497 MBq/μg.66 (link) Activity measurements were made using a Capintec
CRC-15R Dose Calibrator (Capintec, Ramsey, NJ). 89Zr-oxalate
was neutralized with aqueous Na2CO3 (1 M), added
to a solution of 0.5 mol % DFO-bearing liposomes or nanoemulsions
in PBS, and stirred at 37 °C for 2 h. The labeled NPs were separated
from free 89Zr using a PD-10 desalting column (GE Healthcare),
with PBS as the eluent and collecting 0.5 mL fractions. The radiochemical
yield was typically >90%. The fractions containing most activity
(∼1.5–2.0
mL) were used for the experiments. These had a radiochemical purity
of >98%, as determined by SEC radio-HPLC analyses performed on
a Shimadzu
system equipped with a Superdex 10/300 SEC column and a A Lablogic
Scan-RAM radio-TLC/HPLC detector. A flow rate of 1 mL/min was used
with demiwater as the eluent.
