Fluorescence detection is a technique used in various scientific fields, such as chemistry, biology, and physics, to detect and measure the presence of fluorescent molecules or compounds in a sample. This technique relies on the principle of fluorescence, in which certain molecules absorb light at a specific wavelength and then emit light at a longer wavelength. Fluorescence detection is commonly used in analytical chemistry for the quantification of compounds in a sample, as fluorescent molecules can be easily detected and measured with high sensitivity. In biological research, fluorescence detection is often used in imaging techniques, such as fluorescence microscopy, to visualize and study the distribution of specific molecules or structures in cells and tissues. Overall, fluorescence detection is a versatile and powerful tool in research, providing valuable information about the properties and behaviors of fluorescent molecules in a sample.