Luminescence decay time encoding of magnetic micro spheres for multiplexed analysis

Area of Science:

• Materials Science
• Analytical Chemistry
• Biotechnology

Background:

• Optical encoding of microspheres is crucial for multiplexed assays.
• Developing robust and distinguishable codes for microsphere-based detection is an ongoing challenge.

Purpose of the Study:

• To develop a novel optical encoding strategy for magnetic microspheres using luminescent dyes.
• To establish a reliable method for creating a large number of distinguishable bead families.

Main Methods:

• Microspheres were doped with a combination of fluorophores and phosphorescent Ruthenium metal ligand complexes.
• Time-resolved imaging in the microsecond range was used for bead identification.
• A detailed staining procedure and mathematical model were developed for precise dye incorporation.

Main Results:

• A characteristic signature was generated using bead brightness, luminescence decay time, and dual lifetime referencing (DLR).
• Nineteen bead families were successfully prepared with low coefficients of variation (7%, 1.4%, 1.6%).
• The combined features, including bead size, allow for the creation of 840 distinguishable bead families.

Conclusions:

• The developed method provides a robust and scalable approach for creating highly distinguishable optically encoded magnetic microspheres.
• This technology has the potential to significantly advance multiplexed detection and assay development.