Production of 11C for PET imaging using a high repetition rate laser-driven proton source.
Pepe Benliure
Fri, Nov. 29th 2024, 11:00-12:00
Bat 703, p 45, CEA Saclay, Orme des Merisiers

Production of 11C for PET imaging using a high repetition

rate laser-driven proton source.

In recent years, there has been a growing interest in laser-driven ion accelerators as a potential

alternative to conventional accelerators. A particularly promising application is the production of

radionuclides relevant for medical diagnosis, such as 11C for PET imaging. Typically, the

production of these nuclides is centralised in cyclotrons, which reduces the number of facilities

required, but limits the range of usable radionuclides to those with

longer lifetimes.

In this context, compact laser-driven accelerators appear to be an attractive option for the in situ

production of short-lived isotopes. Although the activities required for PET imaging (>MBq) are well

above those achievable by a single laser irradiation (~kBq), the advent of high power, high

repetition rate laser systems open the way to demonstrate relevant activities by continuous

irradiation, provided a suitable target system is developed. In this context, we have developed and

commissioned a target assembly based on a rotating wheel and automatic alignment procedure for

laser-driven proton acceleration at multi-Hertz rates. The assembly, which can host more than 5000

targets and ensuring continuous target replenishment with micron-level precision, has been

demonstrated to provide stable and continuous MeV proton acceleration at rates of up to 10 Hz

using the 45 TW laser system at L2A2 (Univ. of Santiago de Compostela).

The continuous production of 11C via the proton-boron reaction 11B(p,n)11C reaction has been

recently demonstrated using our target assembly on the 1 Hz, 1 PW VEGA-3 system (CLPU,

Spain). In an initial campaign, an activity of ~12 kBq/shot was measured, with a peak activity of

234 kBq achieved through accumulation of 20 consecutive shots. Furthermore, results of a more

recent campaign will be presented, where activation levels in excess of 4 MBq where achieved, as

measured through using coincidence detectors, and supported by online measurements of highflux

neutron generation. We demonstrate that the degradation of the laser-driven ion beam due to

heating of optics is currently the only bottleneck preventing the production of preclinical (~10 MBq)

PET activities with current laser systems. The scalability to next-generation laser systems and new

technologies for the continuous replenishment of the target will allow in the near future the

production of clinical (~200 MBq) activities.


Contact : Barbara SULIGNANO

 

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