Table 4.
Characteristics of selected radiotracers.
| Radiotracer molecules | Dose formulation | Radiolabeling | Radiotracer purification method | |||
|---|---|---|---|---|---|---|
| Isotope | Isotope chelator | Cold moiety | Conditions | Efficiency | ||
| Synthetics | ||||||
| 111In | DTPA | fMLFK | Sephadex G-10 eluent | RT/30 min | 95% | RP-HPLC |
| 99mTc | HYNIC | fMLFK | Sodium phosphate, saline, pH 8 | RT/30–60 min | >96% | RP-HPLC |
| 99mTc | HYNIC | MLF-OMe | Sodium phosphate, saline, pH 8 | RT/30–60 min | >96% | RP-HPLC |
| 68Ga | None | Citrate | Sodium citrate, pH 6-7 | 90°C/10 min | >98% | Anion exchange column |
| 68Ga | None | TAFC | 1.1 M sodium acetate, pH 6-7 | RT/15 min | ≥95% | — |
| 68Ga | None | FOXE | 1.1 M sodium acetate, pH 6-7 | 80°C/20 min | ≥95% | — |
| 111In | DTPA | LTB-4 (DPC11870-11) |
Ammonium acetate, pH 5.5 | RT/30 min | 95% | RP-HPLC |
| 99mTc | HYNIC | LTB-4 (MB88) | Tricine, isonicotinic acid, PBS, SnSO4, pH 7 | 100°C/30 min | 95% | RP-HPLC |
| 18F | pFBA | LTB-4 (MB67) | Sodium acetate, PBS, pH 4–7 | 50°C/>30 min | 65–85% | Evaporation, Δ & N2↑ |
|
| ||||||
| Antibiotics | ||||||
| 99mTc | None | Fluconazole | PYP, SnCl2, KBH4 in 0.1 M NaOH, saline, PBS, pH 7.5 | RT/120 min | 90% | — |
| 99mTc | None | Ciprofloxacin | Sn(II) tartrate | RT/15 min | >40% | — |
| 99mTc | None | Enrofloxacin | Ethanol : water [1 : 1] | 60°C/10 min | 81% | SepPak tC2 cartridge |
| 99mTc | None | Pefloxacin | SnCl2, pH 6 | 100°C/30 min | 98% | — |
| 99mTc | None | Ceftizoxime | Sodium dithionite, N2↑ | 100°C/5 min | >90% | — |
| 99mTc | None | Vancomycin | SnCl2, pH 6-7 | RT/10 min | 99% | — |
| 99mTc | None | Kanamycin | SnCl2, pH 6-7 | RT/25–30 min | 99% | — |
| 99mTc | None | Alafosfalin | SnCl2, pH 6 | RT/5–10 min | 90–95% | — |
| 99mTc | None | Phosphomycin | SnCl2, pH 7 | RT/<1 min | 98% | — |
| 99mTc | None | Cefoperazone | SnCl2, pH 8 | RT/10 min | 98% | — |
| 99mTc | None | Cefuroxime axetil | SnCl2, pH 5 | RT/15 min | 92% | — |
| 99mTc | [99mTc(CO)5] | Novobiocin | Water | RT/30 min | 99% | — |
|
| ||||||
| Biological origin | ||||||
| Cells: | ||||||
| 18FDG | None | Leukocytes | Autologous LEuk, saline | 37°C/30 min | 79% 18F-gran. | Centrifugation |
| 111In | Oxine | Dendritic cells | Allogeneic DC, saline | RT/60 min | 94% | Centrifugation |
| 111In | Oxine | Lymphocytes | Autologous LYM, lym poor plasma | 37°C/10 min | 77% | Centrifugation |
| Macromolecules | ||||||
| 111In | DTPA | hpc-IgG | Citrate | RT/instant | >95% | Centrifugation |
| 99mTc | None | hpc-IgG | Tartrate, SnCl2 | RT/20 min | 90% | — |
| 99mTc | HYNIC | hpc-IgG | Acetate, tricine, SnSO4 | RT/15 min | >95% | — |
| 99mTc | None | Rat pc-IgG | MDP, SnCl2, PBS, N2↑ | RT/20 min | ≥94% | — |
| 99mTc | None | HSA | Saline, SnCl2, N2↑, pH 2–7 | RT/20 min | ≥95% | — |
| 99mTc | None | Infliximab | MDP, SnCl2, PBS, N2↑ | RT/20 min | ≥91% | — |
| 99mTc | None | Fanolesomab | Maltose, tartrate, succinic acid, Sn(II) tartrate, glycine, EDTA, ascorbic acid, pH 6 | 37°C/30 min | ≥90% | — |
| 99mTc | HYNIC | E-selectin peptide (IMP-178) |
2-OH-β-cyclodextrin, Sncl2, acetate, ascorbate | RT/10 min; 100°C/15 min | 92% | — |
| 123I | None | B2702-p (75–84) |
PBS, pH 7 | RT/15 min | >80% | Anion exchange column |
| 99mTc | [99mTc(CO)5] | B2702-p (+his-gly) |
PBS, pH 7 | 100°C/15 min then 80°C/20 min | >90% | — |
| 99mTc | HMPAO | PEG-liposomes | 5% glucose | RT/15 min | 70–80% | Size exclusion on PD-10 column |
| 123I | None | hr-IL-1α | 0.5% BSA in PBS | RT/10 min | 50–80% | Sephadex G-25 column/0.2 μm filter |
| 123I | None | hr-IL-1β | 0.25% gelatine in PBS | RT/10 min; ice/30 min | 25–35% | Sephadex G-25 column/0.2 μm filter |
| 18F | [para-18F-fluoroethyl] | hr-IL-1ra | PBS | 38°C/45 min | 7–24% | HiTrap column/filter |
| 99mTc | None | IL-18bp-Fc-IL-1ra | PBS, pH 7 | RT/30 min | >75% | Sephadex G-25 column |
| 99mTc | HYNIC | hr-IL-2 | SnCl2, tricine, nicotinic acid, pH 6-7 | RT/<60 min | >99% | — |
| 123I | None | hr-IL-2 | 5% glucose | RT/30 min | >96% | HPLC; 30°C/20 min/N2↑ |
| 18F | pFBA | hr-IL-2 | Saline, <10% ethanol | borate pH 8.5 : EtOH [1 : 1], 50°C/10 min | 25–35% | RP-HPLC |
| 99mTc | HYNIC | hr-IL-8 | SnSO4, tricine, nicotinic acid, 0.5% BSA in PBS, pH 7 | 70°C/30 min | >98% | — |
| 99mTc | HYNIC | hr-IL-12 | Stannous tartrate, tricine, pH 6-7 | RT/30 min | 75–85% | G-50 microspin column |
| 99mTc | HYNIC | C5a | SnSO4, tricine, 0.5% BSA in PBS | RT/30 min | >95% | Sephadex G-25 column/0.2 μm filter |
| 99mTc | C5adR | |||||
| Smaller fragments: | ||||||
| 99mTc | None | UBI-29-41 | Sn(II) PYP, potassium borohydride, NaOH, pH 5-6 | RT/60 min | 95% | — |
| 99mTc | HYNIC | UBI-29-41 | SnCl2, tricine, mannitol, pH 4 | RT/>60 min | >96% | — |
RT: room temperature; RP: reverse phase; HPLC: high pressure liquid chromatography; none: isotope is directly bound to the structure of the nonradioactive component; pFBA: para-18F-fluorobenzaldehydel; Δ: heat; PBS: phosphate buffered saline; UBI: ubiquicidin; hpc: human polyclonal; IL: interleukin; hr: human recombinant; LT: leukotriene; DC: dendritic cells; LEuk: Leukocytes; LYM: Lymphocytes.