Droplet-based microfluidic platform for high-throughput, multi-parameter screening of photosensitizer activity

Area of Science:

• Microfluidics
• Photodynamic Therapy
• Microbiology

Background:

• Photodynamic therapy (PDT) requires effective photosensitizers for treating bacterial infections.
• High-throughput screening of PDT agents is crucial for developing new therapies.
• Assessing PDT efficacy traditionally involves time-consuming assays.

Purpose of the Study:

• To develop and validate a droplet-based microfluidic platform for high-throughput PDT photosensitizer efficacy assessment.
• To enable precise control over experimental parameters including light dose and oxygenation.
• To concurrently measure light and dark toxicity of PDT agents.

Main Methods:

• Utilizing a fully integrated droplet-based microfluidic system for cell and photosensitizer encapsulation in pL-volume droplets.
• Incubating droplets for extended periods, followed by addition of viability assay agents.
• Exposing droplets to controlled electromagnetic radiation doses and online detection of live/dead cells.
• Validating results against conventional colony-forming unit (CFU) assays.

Main Results:

• Demonstrated high-throughput assessment of photodynamic therapy photosensitizer efficacy on Escherichia coli.
• Successfully correlated microfluidic viability scoring with established live/dead assays and CFU counts.
• Showcased the platform's capability for concurrent measurement of dark toxicity, photosensitizer concentration, light dose, and oxygenation levels.

Conclusions:

• The droplet-based microfluidic platform offers a robust and efficient method for evaluating PDT agents.
• This technology accelerates the development and testing of novel photosensitizers for therapeutic applications.
• The platform facilitates comprehensive analysis of PDT agent performance under various experimental conditions.