Abstract
514
Objectives: The Trace-Ability’s Tracer-QC is an entirely automated system equipped to preform and report on a total of 10 quality control (QC) tests associated with PET radiotracers (Figure 1). This automated system uses an optical plate reader, a pipetting robot and single-use consumable kits for release testing of PET radiotracers. The automated QC tests are color, clarity, pH, Kryptofix 222, concentration, endotoxin, residual solvents, radionuclidic identity (half-life), radiochemical identity, and radiochemical purity. The single-use consumable kit includes an analysis plate, reagent sets, pipette tips, sample vial, and reaction plates. Traditional QC requires the use of several different instruments (GC, radio-TLC plate reader, dose calibrator, endotoxin test system) as well as tests which require manual interpretation of the test result (color/clarity, pH, radio-TLC standard identity, Kryptofix 222 spot intensity) by operators which can increase human error. The Tracer-QC allows for little to no human interaction thus decreasing human error, and leaving no way to miss a QC test. The results are reported automatically and are completely traceable. After the system is running, QC is conducted unattended. Additionally, the automated instrument confirms no cross-contamination while completing QC as the single sample never leaves the disposable kits. The objective of the current study was to compare Tracer-QC performance to that of traditional QC tests. Methods: F-18 Fludeoxyglucose (FDG) is manufactured and QC is conducted using the standard method approaches and also using the Tracer-QC. One 0.5 mL sample of F-18 FDG is measured into the sample vial from the single-use consumable kits and placed into the removable shielded carrier. All plates and sets are placed into their appropriate spots on the Tracer-QC and testing begins. The traditional QC at MGH is carried out with 0.6mL using the applicable equipment for each test. The comparison is completed by using the data from the past three production runs of F-18 FDG using the traditional QC method and the Tracer-QC. F-18 FDG was synthesized using the GE FASTlab FDG Citrate cassette. The F-18 FDG product has the same quality control specifications, whether it was done via MGH's traditional method or Tracer-QC method as detailed in Table 1. A minor difference is that the Rf of F-18 FDG sample for radiochemical identity (TLC) is specific to the assay; the MGH method is F-18 FDG sample 0.35 - 0.5 and the Tracer-QC is 0.54 - 0.69. Prior to three comparison/cross-validation runs, over 30 observation runs were performed to demonstrate system stability and user benefits. Results: The Tracer-QC and manual, traditional QC are both viable methods for the release of F-18 Fludeoxyglucose, as both produce similar results. Tracer-QC test time is approximately 45 minutes and the MGH traditional QC method is approximately 30 minutes. All results are shown in Table 1. Some of the QC tests used in the traditional method rely on operator interpretation, such as visual inspection for color/clarity, pH strips color to determine pH in 0.5 increments and Kryptofix 222 spot intensity. These assays on the Tracer-QC system are now quantitative tests results removed from operator interpretation of the result. One of the potential concerns of using the Tracer-QC is the chance of a single test failing, as there is no suitable way currently to perform a single re-test solely on its own. Such functionality is currently in development at Trace-Ability.
Conclusions: The Tracer-QC is an equivalent method for the quality control of F-18 Fludeoxyglucose, compared to MGH’s traditional, FDA approved QC testing. The results of the QC validations have been submitted to FDA for review as an acceptable alternative test method for F-18 FDG. The Tracer-QC method of PET radiopharmaceutical QC is a promising method which can streamline and simplify quality control testing.