The first-elution QC cycle on a new generator.

Every generator shipment arrives with a Certificate of Analysis documenting the release-QC values against the EU-GMP Annex 3 monograph: Mo-99 activity at calibration, radionuclidic purity (Mo-99 breakthrough < 0.15 μCi/mCi Tc-99m per USP), radiochemical purity (Tc-99m as TcO₄⁻ > 95 %), sterility and endotoxin. The RSO / senior radiopharmacist signs the CoA into the receipt log before the first elution — this is the paper anchor that keeps the delivered activity provenance intact from manufacturer to hot lab.

Source: EU-GMP Annex 3 § "Release of the finished product"; USP <823> release-testing table.

The generator ships with a matched-volume saline elution pack in the shielded transport container. Receipt check reconciles the saline volume + shielded-vial count against the manifest, verifies the shield integrity (no impact damage, no dose-rate anomaly at contact), and records the shield-front + shield-side dose rate into the RSO log per AERB SC/MED-4. A shipment with damaged shielding or missing saline is refused at the door.

Source: AERB Safety Code SC/MED-4 §5 — nuclear-medicine facility receipt-and-storage requirements.

The first elution is performed under the fume hood into the shielded elution vial supplied. Immediate steps: aspirate the labelled volume, present to the dose calibrator, record the eluted activity against the CoA-predicted activity (correcting for decay from calibration time to elution time using Tc-99m t½ 6.007 h), record the elution efficiency. Expected first-elution efficiency for a fission-based generator sits in the 85 – 95 % range; a value outside that band flags either a saline-flow issue or a calibration-time error.

Source: IAEA TRS-466 §5.3 — generator elution procedure; IAEA TECDOC-1592 §4 — dose-calibrator constancy.

USP-required Mo-99 breakthrough test — measure the eluate through a 6 mm lead attenuator (which stops 140 keV Tc-99m gammas but passes the 740 + 780 keV Mo-99 gammas), compare to the un-attenuated reading, calculate the Mo-99/Tc-99m ratio. Limit: < 0.15 μCi Mo-99 per mCi Tc-99m at administration time. First-elution result gets recorded; subsequent daily elutions rely on the trend chart unless a re-check is triggered by a value approaching limit.

Source: USP <823> Radiopharmaceuticals for PET §Mo-99 breakthrough; IAEA TRS-466 §5.4.

Before feeding the first eluate into a cold-kit labelling (MDP, DTPA, MAG3, MIBI), spot-check the radiochemical purity: apply a drop to a radio-TLC strip, run in the specified solvent (methyl-ethyl-ketone for pertechnetate assay), read on the strip scanner. Expected TcO₄⁻ fraction > 95 %. First elution passes → the CoA claim is validated against the receiving lab. Any subsequent kit-formulation issue is then downstream of the eluate, not the generator.

Source: IAEA TRS-466 §5.5 — radiochemical purity spot check; SNMMI general procedure guidelines.