A fluorometer is an analytical instrument used to measure the fluorescence of a sample. It works by shining a specific wavelength of light onto the sample, which then emits light at a different wavelength. This emitted light is detected and quantified, allowing scientists to analyze the concentration of fluorescent substances in various materials. Fluorometers are commonly used in fields such as environmental monitoring, biochemistry, and medical diagnostics. They can help detect pollutants in water, measure the concentration of biomolecules, and even diagnose diseases by analyzing biological samples.