Final answer:
The PET radiotracer with the shortest half-life is Carbon-11, with a half-life of 20.4 minutes, making it more radioactive than isotopes with longer half-lives. Its rapid decay is beneficial for minimizing patient radiation exposure during PET scans.
Step-by-step explanation:
The PET radiotracer with the shortest half-life among those commonly used is Carbon-11, with a half-life of approximately 20.4 minutes. Radiotracers with shorter half-lives, such as Carbon-11, are generally more radioactive than those with longer half-lives because they undergo decay at a faster rate. In medical imaging, particularly in positron emission tomography (PET) scans, short-lived radioisotopes like Carbon-11 are advantageous because they decay quickly, reducing the exposure time to radiation for patients. Additionally, these short-lived isotopes can be advantageous as they can be incorporated into compounds that participate in physiological processes, allowing for detailed imaging of metabolic activity within the body.