Multi-Pixel Photon Counters for Optofluidic Characterization of Particles and Microalgae.

Area of Science:

• Optofluidics
• Biosensing
• Microfluidics
• Algal analysis

Background:

• Microfluidic devices are crucial for analyzing small particles.
• Sensitive detection methods are needed for microalgae characterization.
• Hydrodynamic focusing enhances sample analysis in microchannels.

Purpose of the Study:

• To develop and validate an optofluidic biosensor for microscale particle and microalgae analysis.
• To characterize different species of microalgae using the developed system.
• To assess the performance of a new generation of multi-pixel photon counters (MPPCs) in biosensing.

Main Methods:

• Fabrication of a microfluidic chip with chevron-shaped grooves for hydrodynamic focusing.
• Integration of multi-pixel photon counters (MPPCs) for sensitive light detection.
• Analysis of fluorescent microspheres and three microalgae species (Chlamydomonas reinhardtii, Chlamydomonas suppressor, Chlorella sorokiniana) via forward scattering.
• Data acquisition and statistical analysis of signal outputs.

Main Results:

• The optofluidic biosensor successfully differentiated between particles and algae species based on signal output.
• Larger particles and cells exhibited larger peak height, width, and area.
• Signal output for the studied algae species fell between that of 3.2 and 10.2 μm beads, enabling characterization.
• The MPPC demonstrated high sensitivity and effectiveness for detecting microscale samples.

Conclusions:

• The developed optofluidic biosensor is effective for characterizing microalgae and microparticles.
• Hydrodynamic focusing and MPPC technology enable sensitive and accurate analysis.
• The system provides a valuable tool for microalgae research and other microscale particle studies.