Cyclotron & PET Radiochemistry Facility

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Introduction

The Lawson Cyclotron & PET Radiochemistry Facility has been operational since 2010 and is home to a GE PETtrace 16.5 MeV cyclotron.

The Cyclotron Facility produces radioactive tracers used for Positron Emission Tomography (PET) imaging in Nuclear Medicine Imaging programs throughout Southern Ontario and is licensed by Health Canada and the Canadian Nuclear Safety Commission.

By producing our own PET tracers, we have enabled clinicians to increase the speed and accuracy of patient diagnosis and treatment.

In addition, in combination with PET/CT, PET/MRI and preclinical PET imaging scanners, the Cyclotron Facility is available to support a wide variety of city-wide research projects and enable researchers to uncover the mysteries of human health in oncology, cardiology, neurology, and other areas.

What is a Cyclotron?

A cyclotron is a type of compact particle accelerator which produces radioactive isotopes that can be used for medical imaging procedures. Stable, non-radioactive isotopes are put into the cyclotron in which charged particles (protons) accelerate in a spiral outwards from the machine’s centre, accelerated by alternating kicks of electric voltage and steered along their path by a magnetic field. Once the high-speed, high-energy protons get to the edge of the cyclotron chamber, the particles are directed down beamlines where they react with a stable atom on a liquid or solid target, creating radioactive isotopes for nuclear medicine.

There are over 1500 cyclotron facilities around the world. Unlike nuclear reactors, medical cyclotrons do not use nuclear materials.

What is a PET Radiochemistry Facility?

The PET Radiochemistry Facility is dedicated to the production, quality assurance and dispensing of sterile, clinical grade PET tracers or radiopharmaceuticals. As many of the radioisotopes are intended for use in medical imaging or clinical research, the PET Radiochemistry Facility meets stringent standards for the manufacture of pharmaceuticals according to Health Canada Drug Directive policies, known as Good Manufacturing Practices (GMP) and, thus, our facility is routinely audited by Health Canada for quality and safety control purposes.

The Lawson Cyclotron Facility has lab space dedicated for researchers to work safely with radioactive materials. Once produced in the cyclotron, the radioactive isotopes are transferred via under floor conduits to a heavily shielded "hot cell" where they are run through sophisticated chemistry equipment called automated synthesis units (ASUs). These are used to take the "raw" isotopes, synthesize, purify and then sterilize them into PET tracers such as [18F]FDG.

At Lawson, we have a number of ASUs for synthesizing various radioisotopes, including F18, C11, N13, O15 and solid target radioisotopes such as Ga68 and Zr89.

In this area, most of the work is done in large ASUs built specifically for production of large quantities of PET tracers. It is here that the world’s most popular PET tracer, Fluorodeoxyglucose (FDG), is produced by the Lawson Cyclotron Facility and shipped throughout southern Ontario.

Each production of PET tracers is tested and evaluated according to standards that are the equivalent to those used in the production of pharmaceuticals. Chemical composition, purity, pH and other criteria are measured using complex equipment such as Gas Chromatograph, High-Performance Liquid Chromatograph, Ultra-Performance Liquid Chromatograph, Thin-Layer Chromatograph.

All PET tracers that are to be used for human imaging are transferred from the Production Lab into the Lawson Cyclotron Facility Class C Clean Room where they are dispensed within a Class A hotcell into sterile vials.

Importance of PET

The use of Positron Emission Tomography (PET) and the development of new PET tracers will play a role of increasing importance in our fight against cancer, cardiac and mental health illnesses. PET is non-invasive and the most advanced medical diagnostic imaging technology available today, producing a three-dimensional image of functional processes in the body.

PET Tracers

In the hospital nuclear medicine department, the PET radiopharmaceutical is injected into a patient who undergoes PET scans. As the radioisotope in the radiopharmaceutical decays, it releases energy that is detected by the scanner which generates an image that can lead to improved detection, diagnosis and treatment of diseases such as cancers, heart disease and diseases of the brain.

Equipment

Click on the tabs for more information on the equipment of the Lawson Cyclotron Facility

GE PETtrace 880 cyclotron (16.5 MeV)
Solid target radioisotope production capability
(Ga68, Zr89, Tc99m)
Liquid target radioisotope production capability
(F18, C11, N13, O15)

Comecer Hotcells

Fastlab ASU

Tracerlab ASU

Neptis Perform ASU

Synthra ASU

Ultra-Performance Liquid Chromatography (UPLC)

Gas Chromatography (GC)

Future Directions

We are always seeking academic and industrial collaborators interested in radiopharmaceutical research

Develop new tracers for PET imaging of biomarkers, focusing on cancer, heart disease and mental illnesses
Synthesize, optimize chemistry, and prepare PET tracers to GMP specifications for use in humans
Validate PET tracers via in vitro experiments and our small animal microPET and microSPECT scanners
Verify with large animal imaging on a clinical PET/CT, SPECT/CT or PET/MRI scanner
Conduct clinical trials to help translate into clinical practice

Partners

St. Joseph’s Health Care London
London Health Sciences Centre
Western University
Canada Foundation of Innovation
Ontario Research Fund

Safety

Click on the tabs for more information on the safety of the Lawson Cyclotron Facility

As a device that produces radioactivity, cyclotrons require licensing by the Canadian Nuclear Safety Commission (CNSC). Cyclotrons are not a new technology and the CNSC has extensive experience with ensuring safety of staff and the general public from cyclotron facilities across Canada.

The design of the entire Cyclotron & PET Radiochemisty Facility, including safety considerations for staff and the general public, has been reviewed and approved by the CNSC and conforms to the health and safety policies of St. Joseph’s Healthcare, London. In addition, the CNSC conducts regular inspections of the Lawson Cyclotron Facility radiation safety program to ensure safety and compliance with federal safety regulations.

The facility has multiple levels of shielding, protection and monitoring to ensure safe operation. Specialized air and waste handling systems guard against accidental releases of radioisotopes outside the facility. Lab work with radioisotopes take place in sealed and shielded hot cells designed to contain spills. All cyclotron safety systems are tested on a regular basis to ensure they are functioning according to design.

Isotopes produced in the facility do not last very long and decay to negligible amounts in a matter of hours.

Personnel working in the Cyclotron Facility, as well as all staff working with radioactive chemicals, wear monitoring equipment (badges) that measure exposure to radioactivity. The packaging and transport of the radioactive substances for delivery to local hospitals is done safely in accordance with Transport Canada regulations for the transport of dangerous goods (TDG, class 7).

Access to the Cyclotron & PET Radiochemistry Facility is tightly controlled through a variety of safeguards.

For more information, visit the CNSC website http://nuclearsafety.gc.ca/

The Lawson Cyclotron & PET Radiochemistry Facility operates under an operating license issued by the Canadian Nuclear Safety Commission, a federal government agency endowed under the Nuclear Safety and Control Act (1997) with the authority to regulate all nuclear facilities in Canada. Ongoing communication with our community is a key part of our operation. The Cyclotron Facility uses a public disclosure protocol to relate information to the public on the issues relevant to licensed activities in the facility, including health and safety, security, and operational updates.

For more information: cyclotron-pidp-2021.pdf