The phasefluorimetry method of lifetime sensing has several attractive
features such as high sensitivity, high level of noise discrimination,
the capability to use well-developed and easily accessible light
modulation techniques, and a relative insensitivity to fluorophore
bleaching and excitation light fluctuations. However, the
phasefluorimetry method remains relatively expensive and complicated due
to the necessity of precision digital electronic elements (such as
frequency synthesizers) to obtain high quality phase measurements.
This invention is for a new method of fluorescence lifetime-based
chemical/biological sensor monitoring called frequency fluorimetry.
This technique doesn’t require external signal synthesizers and/or the
cross correlation detection technique in order to obtain high precision
measurements, making it a much less expensive alternative to existing
lifetime-based instruments. The detection platform consists of an
optoelectronic circuit which exhibits self-oscillations with frequencies
in the neighborhood of the inverse of the fluorescence lifetime.
Changes in the fluorescence lifetime optically alter the resonance
characteristics of the circuit. This, in turn, causes a frequency shift
in the self-oscillations which can be measured very precisely with a
Fluorescence lifetime-based chemical and biological sensors are good
candidates to satisfy the detection needs for different applications
including medical, pharmaceutical, environmental, and military
biochemical warfare detection.
This system provides lifetime-based measurements with inexpensive,
off-the-shelf components. Because the resonance frequencies of many
fluorophores are in the neighborhood of 40 to 50 MHz, systems may be
designed and constructed using low cost electronic components from the
cellular phone industry. The design is scalable, so the basic
optoelectronic circuit maybe duplicated many times in order to provide
for sensor array monitoring. The system is fast because the response
of the resonance frequency to lifetime changes is almost instantaneous.
Limitations on the time constants of the sensor platform are determined
by the frequency counter. For example, using an inexpensive
computer-based frequency counter (which may monitor 1 to 64 channels
simultaneously), time constants obtained are as short as one second.
STC has filed intellectual property on this exciting new technology and is currently exploring commercialization options. If you are interested in information about this or other technologies, please contact Arlene Mirabal at firstname.lastname@example.org or 505-272-7886.