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Optimization and Stabilization of Automated Synthesis Systems for Reduced 68Ga-PSMA-11 Synthesis Time

68Ga-PSMA-11 합성 시간 단축을 위한 자동합성장치의 최적화 및 안정성 연구

  • Ji hoon KANG (Innovation Center for Molecular Probe Development, Department of Nuclear Medicine, Chonnam National University Hwasun Hospital) ;
  • Sang Min SHIN (Innovation Center for Molecular Probe Development, Department of Nuclear Medicine, Chonnam National University Hwasun Hospital) ;
  • Young Si PARK (Innovation Center for Molecular Probe Development, Department of Nuclear Medicine, Chonnam National University Hwasun Hospital) ;
  • Hea Ji KIM (Innovation Center for Molecular Probe Development, Department of Nuclear Medicine, Chonnam National University Hwasun Hospital) ;
  • Hwa Youn JANG (Innovation Center for Molecular Probe Development, Department of Nuclear Medicine, Chonnam National University Hwasun Hospital)
  • 강지훈 (화순전남대학교병원 핵의학과 분자프로브혁신센터) ;
  • 신상민 (화순전남대학교병원 핵의학과 분자프로브혁신센터) ;
  • 박영시 (화순전남대학교병원 핵의학과 분자프로브혁신센터) ;
  • 김혜지 (화순전남대학교병원 핵의학과 분자프로브혁신센터) ;
  • 장화연 (화순전남대학교병원 핵의학과 분자프로브혁신센터)
  • Received : 2024.06.11
  • Accepted : 2024.06.17
  • Published : 2024.06.30

Abstract

Gallium-68-prostate-specific membrane antigen-11 (68Ga-PSMA-11) is a positron emission tomography radiopharmaceutical that labels a Glu-urea-Lys-based ligand with 68Ga, binding specifically to the PSMA. It is used widely for imaging recurrent prostate cancer and metastases. On the other hand, the preparation and quality control testing of 68Ga-PSMA-11 in medical institutions takes over 60 minutes, limiting the daily capacity of 68Ge/68Ga generators. While the generator provides 1,110 MBq (30 mCi) nominally, its activity decreases over time, and the labeling yield declines irregularly. Consequently, additional preparations are needed, increasing radiation exposure for medical technicians, prolonging patient wait times, and necessitating production schedule adjustments. This study aimed to reduce the 68Ga-PSMA-11 preparation time and optimize the automated synthesis system. By shortening the reaction time between 68Ga and the PSMA-11 precursor and adjusting the number of purification steps, a faster and more cost-effective method was tested while maintaining quality. The final synthesis time was reduced from 30 to 20 minutes, meeting the standards for the HEPES content, residual solvent EtOH content, and radiochemical purity. This optimized procedure minimizes radiation exposure for medical technicians, reduces patient wait times, and maintains consistent production schedules, making it suitable for clinical application.

68Ga-PSMA-11은 전립선특이막항원(PSMA)에 결합하는 Glu-urea-Lys 기반 리간드에 68Ga 방사성동위원소를 표지한 PET 제제로, 재발성 전립선암 및 전이의 진단과 치료를 위한 영상화에 널리 사용한다. 그러나 의료기관에서 68Ga-PSMA-11을 제조하고 품질검사 시험 결과가 나올 때까지의 시간은 평균 60분 이상 소요되어, 하루에 사용할 수 있는 68Ge/68Ga 제너레이터 용량이 제한된다. 또한 제너레이터의 1,110 MBq (30 mCi)의 명목상 활성을 제공하지만 시간이 지남에 따라 감소하고, 표지 수율이 불규칙적으로 저하된다. 이로 인해 의료기관에서는 추가 조제를 통해 동일한 용출을 유지해야 하며, 이 과정에서 작업자의 피폭 위험이 증가하고, 환자의 대기 시간이 길어지며, 제조 스케줄 조정이 불가피한 임상적 문제가 발생한다. 본 연구는 이러한 문제를 해결하기 위해 68Ga-PSMA-11의 조제 시간을 단축하고 자동합성장치를 최적화하는 것을 목표로 하였다. 자동합성장치를 이용한 합성 절차에서 68Ga과 PSMA-11 전구체의 반응 시간을 단축하고 불순물 제거 세척 단계의 횟수를 조절하여 동일한 품질을 유지하면서도 더 신속하고 경제적인 방법을 시험했다. 그 결과, 최종 합성 시간을 30분에서 20분으로 단축하였고, HEPES 함량, 잔류용매 EtOH 함량, 방사화학적 순도 등의 품질 기준을 만족시켰다. 이는 추가 조제로 인한 작업자의 피폭 문제와 환자의 대기 시간을 줄이고, 제조 스케줄 조정에도 문제가 없는 최적의 절차로 임상에서 적용할 수 있음을 시사한다.

Keywords

Acknowledgement

This paper was supported by the Korean Association of Medical Technologists in 2024 and proceeded by support project for thesis submission by member practitioners. Proofreading performed by Im KI.

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