Bi 213
45.6 m
β- 0.4...
γ (440...)
α 5.875, 5.558

Chemical properties

Bi-213 is usually employed in trivalent state. It can be labelled with macrocyclic chelators such as DOTA, but other chelators can be considered too . The ionic radius is 117 pm.

Nuclear properties

Bi-213 decays with a half-life of 0.760(1) hours. It decays by 97.8% beta-minus emission to very short-lived Po-213 (T1/2 = 3.7 µs) that decays in turn with 100% alpha emission to Pb-209 (T1/2 = 3.2 h), further decaying by beta-minus emission to Bi-209. Moreover, Bi-213 decays by 2.2% alpha emission to Tl-209 (T1/2=2.16 min) that decays via Pb-209 to Bi-209. Including its short-lived Po-213 daughter, the cumulative alpha emission is 100% per Bi-213 decay with an average alpha energy of 8.32 MeV.

Bi-213 emits gamma rays at 440.5 keV (25.94(15)%). This enables SPECT-imaging with high energy collimators .

Production

Ac-225 is produced by elution from Th-229 generators. It is loaded onto a generator from which Bi-213 can be eluted .

Distribution

Bi-213 generators will be shipped from the PRISMAP production facility JRC Karlsruhe (JRC, Karlsruhe, International).

Examples of use

  • Bi-213 has been used preclinically and clinically with antibodies and peptides .
  • A clinical trial with Bi-213-DOTA-substance P has shown promising results for glioblastoma therapy .

Purity grades available

GLP

No carrier added (n.c.a.)

Yes
ParameterSpecifications
Half-life9.92 d for Ac-225 mother, 45.6 min for Bi-213 eluate
DaughterDecay chain of Bi-213 involves radioactive Po-213 or Tl-209 and Pb-209, leading to Bi-209.
Branching Ratio/DecayCumulative 100% α, 200% β-
ProductionTh-229→ Ra-225 → Ac-225 generator
Purificationtwo step purification process (cation exchange and extraction chromatography)
Chemical Formn.c.a. Bi-213, depending on Ac-225 load on the generator
Specific Activity
Radionuclidic PurityU-233/Th-229 < 90 ppm (limit of detection); Ra-225 < 20 ppm (limit of detection)
(Po-213, Pb-209 not considered)
Radiochemical Purity>95% of radiolabelled compound (e.g. DOTATOC)
Chemical Purity>99.98%
Identification440 keV gamma line present
Appearancecolourless eluate
pHn.a.; depending on labelling conditions
Activity availablemax. 1000 MBq reserved for clinical studies every two months, upon request
Availabilityevery two months, smaller amounts for preclinical studies upon request
GradeGLP, n.c.a.
Other informationelution protocol is adaptable to the compound to be labelled, depending on the chelator and labeling protocol

Applications

  • SPECT

Point of supply

  • Karlsruhe, Germany

Involved production facilities

JRC, International