Fluorescence Multi-Detection Device Using a Lensless Matrix Addressable microLED Array.

Area of Science:

• Micro- and Nanotechnology
• Biomedical Engineering
• Photonics

Background:

• Traditional molecular diagnostic instrumentation often relies on bulky lasers and optical components.
• There is a need for miniaturized, integrated systems for point-of-care molecular diagnostics.
• Fluorescence-based measurements are crucial for detecting biomolecules but require sophisticated equipment.

Purpose of the Study:

• To develop and demonstrate a novel Point-of-Care system for molecular diagnosis (PoC-MD).
• To integrate Gallium Nitride (GaN) and Complementary Metal-Oxide-Semiconductor (CMOS) technologies into a micro-system for fluorescence measurements.
• To enable analysis of both fluorescence intensity and lifetime at the point of care.

Main Methods:

• Fabrication of a hybrid micro-structure combining a 32x32 addressable GaN microLED array with a 16x16 SPAD CMOS array.
• Face-to-face placement of GaN microLEDs and CMOS single-photon avalanche diodes (SPADs) for efficient light detection.
• Development of integrated drivers on a custom CMOS chip for the GaN microLED array.

Main Results:

• The developed PoC-MD system enables fluorescence measurements on 32x32 spots.
• Achieved a limit of detection of approximately 1/4 µM for long lifetime (>10 ns) fluorophores.
• Demonstrated proof-of-concept measurements using Qdot™ 605 and Amino PEG Qdot™ 705, including simultaneous detection.

Conclusions:

• The hybrid GaN-CMOS micro-system successfully replaces conventional bulky instrumentation for fluorescence measurements.
• The PoC-MD system is suitable for sensitive detection of specific fluorophores.
• This technology holds promise for advancing point-of-care molecular diagnostics with enhanced sensitivity and portability.