Label-Free Biosensing with High Selectivity in Complex Media using Microtoroidal Optical Resonators.

Area of Science:

• Biomedical Engineering
• Materials Science
• Analytical Chemistry

Background:

• Label-free biosensors using optical microcavities offer high sensitivity for molecular interactions.
• Extreme sensitivity makes these biosensors prone to non-specific binding in complex media, limiting field applications.
• Current applications are restricted to controlled laboratory settings, hindering real-world use.

Purpose of the Study:

• To develop a novel surface modification strategy for optical microcavity biosensors.
• To enable highly selective and sensitive biosensing in complex biological and environmental samples.
• To overcome limitations of non-specific interactions in advanced biosensing platforms.

Main Methods:

• A robust, silane-based surface coating was developed.
• The coating was engineered to be simultaneously protein-resistant and bioconjugable.
• Functionalized microtoroid biosensors were tested for their performance in complex media.

Main Results:

• The novel surface coating effectively prevented non-specific interactions in functionalized microtoroids.
• The modified biosensors maintained high sensitivity and reliability for molecular detection.
• Successful biosensing was demonstrated within complex media, overcoming previous limitations.

Conclusions:

• The proposed surface modification strategy significantly enhances the selectivity and robustness of optical microcavity biosensors.
• This approach allows for reliable biosensing in complex samples, expanding potential applications.
• The strategy paves the way for real-world applications, including early disease detection and food safety monitoring.