autofluorophore

An autofluorophore is a naturally occurring fluorescent molecule within a biological sample. These molecules emit light at specific wavelengths when excited by a light source, typically of a shorter wavelength. Unlike extrinsic fluorophores, which are introduced into a sample to label specific structures or molecules, autofluorophores are endogenous components of cells and tissues.

Common autofluorophores include flavins, porphyrins, and pyridine nucleotides like NADH and FAD. These molecules play crucial roles in cellular metabolism and other biological processes. For instance, flavins and pyridine nucleotides are involved in redox reactions and energy production. Porphyrins are key components of hemoglobin and cytochromes.

The presence of autofluorophores can sometimes interfere with fluorescence microscopy experiments, especially when trying to detect weakly fluorescent extrinsic labels. Their spectral properties often overlap with those of commonly used dyes, making it challenging to differentiate between endogenous and exogenous fluorescence. Researchers often employ strategies to minimize autofluorescence, such as selecting excitation and emission wavelengths that are specific to the extrinsic fluorophore or using specific imaging modalities. Understanding the spectral characteristics of autofluorophores is essential for accurate interpretation of fluorescence imaging data in biology and medicine.