Biofluorescence vs. Bioluminescence: What’s the Difference?

Humans have always been fascinated by light-producing organisms. Biofluorescence and bioluminescence are two naturally occurring phenomena that people can observe in certain creatures that have evolved to produce or emit light. While these capabilities may seem very similar, biofluorescence and bioluminescence have unique characteristics that make them quite distinct from one another. In this post, we will discuss these differences.

What Is Biofluorescence? 

Biofluorescence is not a chemical reaction. Biofluorescent plants and organisms absorb low wavelength or dim light, then emit high wavelength light that makes the creatures glow against a dark background. This means biofluorescent organisms do not give off light from their own power source, nor is it a chemical reaction. The light emitted is a completely different color from what’s absorbed — usually green, red or orange.

Examples of biofluorescence are ocean organisms such as corals, jellyfish and a wide array of fish that use this capability for communication, camouflage or mating purposes. However, many additional functions may also explain this phenomenon.

New discoveries in biofluorescent coloring may be used to develop new products, especially in medicine.

How to Measure Biofluorescence

A fluorometer generally measures biofluorescence. This instrument measures the various characteristics of fluorescence, including its intensity and the wavelength distribution of the emission after the sample is excited. The unit generally used is relative fluorescence units (RFU).

What Is Bioluminescence? 

Unlike biofluorescence, where an organism emits light upon excitation by an external light source, bioluminescence is generated by a chemical or biological reaction created within the organism’s body. It’s similar to the reaction you witness when cracking a glow stick. Because it doesn’t produce much heat, this reaction is sometimes called cold light.

Biofluorescence examples are as varied as the creatures capable of emitting light. Fireflies, for example, use biofluorescence to communicate with one another. Deep-sea creatures, such as angler fish, use this capability to locate food and attract or mimic prey. Other organisms release a bioluminescent fluid to defend themselves.

Bioluminescence is a more challenging phenomenon to study than biofluorescence as most animals lose their luminescent capabilities when captured due to damage or stress.

How to Measure Bioluminescence 

A luminometer usually measures the photons or packets of light emitted from bioluminescent organisms. This instrument samples light output and most luminometers are simple and relatively inexpensive. Bioluminescence readings are expressed as relative light units (RLU).

Advanced Color Matching Technology With HunterLab

As humankind seeks to understand the stunning nature of biofluorescence and bioluminescence, the advantages of these naturally occurring color phenomena hold incredible promise. From lifesaving uses in medicine to investigating biological mysteries, people have only just started to tap the potential uses for biofluorescence and bioluminescence.

As these phenomena become more commonplace, HunterLab is committed to helping your company create and communicate how your products look with first-class color measurement technology. Put our spectrophotometers to work for you. Learn more when you contact HunterLab.