Multiscattering-enhanced optical biosensor: multiplexed, non-invasive and continuous measurements of cellular...

Area of Science:

• Biomedical Engineering
• Analytical Chemistry
• Cellular Metabolism

Background:

• Continuous monitoring of cellular biomarkers like hydrogen peroxide (H2O2), lactate, and glucose is crucial for understanding cell metabolism.
• Existing methods often lack the multiplexing, non-invasive, and continuous detection capabilities required for comprehensive cellular analysis.

Purpose of the Study:

• To develop and demonstrate a multiscattering-enhanced optical biosensor for the simultaneous, non-invasive, and continuous detection of H2O2, lactate, and glucose.
• To enable real-time monitoring of cellular metabolic processes in living organisms.

Main Methods:

• An optical sensing scheme based on monitoring the oxidation state of cytochrome c (cyt c).
• Enzymatic conversion of analytes to H2O2, causing cyt c oxidation.
• Contact microspotting to create sensing spots with cyt c, glucose oxidase (GOx), or lactate oxidase (LOx).
• Embedding sensing spots in a multiscattering porous medium to enhance optical signals and using a microfluidic system for multiplexed detection.

Main Results:

• Achieved limits of detection as low as 240 nM for lactate and 110 nM for glucose.
• Demonstrated multiplexed and crosstalk-free detection capabilities in a microfluidic setup.
• Successfully studied glucose uptake and H2O2 generation in the green alga Chlamydomonas reinhardtii.

Conclusions:

• The developed optical biosensor is a powerful, multifunctional tool for studying biochemical processes at the cellular level.
• This technology facilitates real-time, in-situ analysis of key metabolic biomarkers.
• The biosensor opens new avenues for understanding cellular responses and metabolic dynamics in complex biological systems.