They can stay stable for years, whereas radioactive molecules must be used soon after manufacturing and require special training for use. (sciencedaily.com)
The researchers developed an oxygen - sensitive molecular beacon that emits ultrasound signals in response to light, a process called photoacoustic imaging — a less invasive, higher resolution and less costly method than the current clinical standard, which uses radioactive molecules and positron emission tomography scans. (sciencedaily.com)
When an organism dies, an unstable radioactive molecule present in living tissues, known as radiocarbon, begins to decay at a known rate. (sciencedaily.com)