Background suppression in frequency-domain fluorometry

Area of Science:

• Analytical Chemistry
• Spectroscopy
• Biophysics

Background:

• Gated detection is crucial for time-domain fluorometry to eliminate short-lived autofluorescence.
• Frequency-domain fluorometry traditionally lacks direct methods for autofluorescence suppression.
• Interfering autofluorescence complicates the analysis of long-lived fluorophores in frequency-domain measurements.

Purpose of the Study:

• To introduce a direct method for real-time autofluorescence suppression in frequency-domain fluorometry.
• To enable accurate measurements of long-lived fluorophores by removing background noise.
• To provide a universally applicable technique for frequency-domain fluorescence spectroscopy.

Main Methods:

• Utilized a gated detector synchronized with a pulsed excitation light source.
• Introduced a time delay after each excitation pulse for prompt autofluorescence decay.
• Employed a long-lifetime standard for reference signal generation under identical conditions.

Main Results:

• Demonstrated real-time suppression of autofluorescence in frequency-domain fluorometry.
• Showcased that sample and reference signals can be analyzed without additional processing.
• Simulations confirmed the method's ability to resolve single and multiexponential decays amidst autofluorescence.

Conclusions:

• The developed gated detection method effectively suppresses autofluorescence in frequency-domain fluorometry.
• This technique simplifies data analysis and enhances the accuracy of measurements for long-lived fluorophores.
• The method offers a significant advancement for fluorescence spectroscopy applications requiring background noise reduction.