M13 bacteriophage-based high-sensitivity Fabry-Pérot etalon for detecting humidity and volatile organic compounds

Area of Science:

• Biomaterials Science
• Nanotechnology
• Sensor Technology

Background:

• M13 bacteriophage (M13) offers tunable properties for advanced sensor applications.
• Existing methods lack precise dynamic measurement for M13-target interactions.
• Optimizing M13 reactivity and binding affinity is key for sensor enhancement.

Purpose of the Study:

• To develop and demonstrate an M13-based dynamic actuator in a Fabry-Pérot etalon (M13-FPE) for precise environmental sensing.
• To enable dynamic measurement of M13's response to humidity and volatile organic compounds (VOCs).
• To establish a method for quantifying M13 swelling and binding affinities.

Main Methods:

• Fabrication of an M13-FPE using M13 as a dynamic spacer between optical mirrors.
• Optimization of transmission spectrum by adjusting mirror reflectance and cavity gap (dM13).
• Measurement of spectral changes in a rainbow-color-dotted (RCD) pattern using a customized spectrometer.

Main Results:

• Precise dynamic measurement of dM13 changes revealed ~3% swelling for ethanol and 0.3% for isopropyl alcohol.
• M13 demonstrated binding affinities of 827 ppb for ethanol and 158 ppb for isopropyl alcohol.
• Low reactivity was measured with high precision, showing an error of 0.03 nm in peak wavelength change rate.

Conclusions:

• The M13-FPE serves as a highly sensitive and precise sensor for humidity and VOCs.
• This M13-based actuator provides a robust platform for dynamic interaction measurements.
• The study highlights M13's potential for next-generation functional material-based sensors.