Phosphorescent Microspheres – Long Afterglow Particles

Phosphorecent Beads - Yellow Green Afterglow

Phosphorescent microspheres in particle sizes 10 to 600 microns are now available from Cospheric LLC. These phosphorescent particles are 90% spherical and appear to be off-white under ordinary daylight or regular room illumination.  However, when the lights are turned off these phosphorescent particles exhibit phosphorescent yellow-green after-glow.

The spheres have tight particle size distributions and are > 90% within size range.  Polymer spheres that incorporate proprietary phosphorescent ingredient have a melting point of 115°C , and are mechanically stable past 90°C.  Phosphorescent beads are also inert in most solvents.

Intensity of Phosphorescent Afterglow:

Intensity according to DIN 67510-1

800 mcd/m² at 1 minute
180 mcd/m² at 5 minutes
90 mcd/m² at 10 minutes
12 mcd/m² at 1 hour
5 mcd/m² at 2 hours

Excitation and Phosphorescent Emission Curve:

Fluorochromes – Excitation and Emission Wavelengths

Below is a very useful table of various Fluorochromes that can be used in research requiring precise responses.  For more information about Fluorescent Microspheres that utilize fluorochromes check out this related article. “Fluorescent Microspheres – Properties and Applications”

The fluorochrome table is also available for download as a pdf.

Fluorescent Microspheres – Properties and Applications

Fluorescent microspheres are round spherical particles that emit bright colors when illuminated by UV light. Ability to emit intense color under UV (black light) illumination provides contrast and visibility of microspheres relative to background materials. In addition to the benefits of conventional high quality microspheres, such as sphericity, smoothness and spreadability among others, fluorescent spheres offer extra sensitivity and detectability for analytical methods. For example, fluorescent microbeads are often used as traces to simulate spread of viruses in medical research.

Typical applications of fluorescent spheres include: testing of filtration media and systems, vial and container cleaning studies, flow tracing, flow visualization, and fluid mechanics studies, medical imaging and flow cytometry, fluorescence microscopy and photography, as well as biomedical technology research, qualification and validation of medical devices, biomedical diagnostics, process troubleshooting and process flow among others. Specifically fluorescent microspheres are often used for water- and air-flow testing and bead-based diagnostic applications. New unique applications of fluorescent spheres are being discovered daily.

Fluorescent spheres have a unique ability to appear translucent (clear) and practically invisible under ordinary light, and emit intense visible color when energized by ultraviolet (UV) light. This effect allows scientists and engineers to design blind tests and controlled experiments (e.g. simulate spread of viruses) where the microspheres are invisible to the operator doing the procedure until after the fact, therefore, eliminating any operator bias and uncertainty in the validity of experiment. This unique feature of fluorescent microspheres has numerous applications in biomedical research and process troubleshooting. Continue reading “Fluorescent Microspheres – Properties and Applications” »