Patents
by staff and students of the Laboratory for Fluorescence Dynamics (LFD).
2020
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System and method for hyperspectral imaging in highly scattering media by the spectral phasor approach using two filters.
Patent US20200378830A1, 03 Dec 2020.An imaging system comprises an excitation light source, a directing element positioned to direct light from the excitation light source toward a sample, a detector configured to measure incoming light from the sample, a filter cavity positioned between the sample and the detector, a first filter configured to be inserted into the filter cavity, a sine filter configured to be inserted into the filter cavity, and a processing unit communicatively connected to the detector, configured to receive image data from the detector to form an image. Methods of constructing a hyperspectral image of a sample are also described.
2019
Stringari C, Gratton E, Digman MA, Donovan P.
Phasor method to fluorescence lifetime microscopy to discriminate metabolic state of cells in living tissue.
Patent US10222335B2, 05 Mar 2019.A label-free imaging method to monitor stem cell metabolism discriminates different states of stem cell as they differentiate in a living tissues. We use intrinsic fluorescence biomarkers and the phasor approach to Fluorescence Lifetime Imaging Microscopy (FLIM). We identify and map intrinsic fluorophores such as collagen, retinol, retinoic acid, flavins, nicotinamide adenine dinucleotide (NADH) and porphyrin. We measure the phasor values of germ cells in C. Elegans germ line. Their metabolic fingerprint cluster according to their differentiation state, reflecting changes in FAD concentration and NADH binding during the differentiation pathway. The phasor approach to lifetime imaging provides a label-free, fit-free and sensitive method to identify different metabolic state of cells during differentiation, to sense small changes in the redox state of cells and may identify symmetric and asymmetric divisions and predict cell fate.
2018
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Apparatus and method for an inclined single plane imaging microscope box (iSPIM box).
Patent US9874736B2, 23 Jan 2018.An apparatus for inclined single plane Illumination microscopy of a sample includes a laser for launching excitation light beams at a plurality of wavelengths, a laser beam expander, an injection arm optically coupled to the laser beam expander, a conventional back-to-back microscope system, a universal dichroic mirror optically coupled to the injection arm to direct the excitation light beams into the conventional back-to-back microscope onto a sample plane in an imaging plane, and to receive fluorescence light from the sample, a universal optical adaptor optically coupled to the universal dichroic mirror, a re-imaging component optically coupled to the universal optical adaptor; and a camera output connector optically coupled to the re-imaging component, where the laser beam expander, injection arm, universal optical adapter, re-imaging component, and camera are combined in a modular unit which is arranged and configured to be coupled to the conventional back-to-back microscope.
2017
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System and method for digital parallel frequency fluorometry.
Patent EP2529152B1, 15 Nov 2017.
2015
Lanzanò L, Digman MA, Gratton E.
Nanometer-scale optical imaging by the Modulation Tracking (MT) method.
Patent US9110282, 18 Aug 2015.An optical imaging method based on a feedback principle in which the specific scan pattern is adapted according to the shape of the sample. The feedback approach produces nanometer-resolved three dimensional images of very small and moving features in live cells and in a matter of seconds. Images of microvilli in live cultured opossum kidney cells expressing NaPi co-transporter proteins with different GFP constructs and images of cell protrusions in a collagen matrix are produced with a resolution of about 20 nm. Along cell protrusions in three dimensional cellular adhesions could be identified to the extracellular matrix.
Zhao W, Kang Dk, Zhang K, Ali MM, Eckert MA, Li F, Gratton E, Digman MA, Labanieh L, Lu M.
Encapsulated sensors and sensing systems for bioassays and diagnostics and methods for making and using them.
Patent WO2015048173, 30 Apr 2015.In alternative embodiments, the invention provides high throughput, multiplexed systems or methods for detecting a biological, a physiological or a pathological maker, or a single molecule or a single cell using a droplet microfluidics system integrated with use of a sensor or a sensing system, an aptamer, or a DNAzyme. In alternative embodiments, the sensor or sensing system comprises a nucleic acid based, an antibody based, an enzyme based or a chemical based sensor or sensing system. In alternative embodiments, the invention provides methods for detecting a biological, a physiological or a pathological marker, or a single molecule or a single cell using a droplet system integrated with rapid and sensitive fluorescence detection systems including, for example, a 3D Particle Detector. In alternative embodiments, the invention provides systems comprising Integrated Comprehensive Droplet Digital Detection (IC 3D).
2014
Gratton E, Dvornikov AS, Crosignani V.
Apparatus and method for light emission detection for in-depth imaging of turbid media.
Patent US8692998, 08 Apr 2014.An apparatus and method for in-depth fluorescence imaging using two-photon fluorescence imaging in turbid media. The apparatus includes a detector which can significantly enhance the use of a detection method that allows to efficiently collect scattered fluorescence photons from a wide area of the turbid sample. By using this detector it is possible to perform imaging of turbid samples, simulating brain tissue at depths up to 3 mm, where the two-photon induced fluorescence signal is too weak to be detected by previous means used in conventional two-photon microscopy. The detector separates the excitation and detection optics which allows a more efficient collection of fluorescence and enhancing the possible imaging depth.
2012
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System and method for digital parallel frequency fluorometry.
Patent US8330123, 11 Dec 2012.A system and method is provided for improved fluorescence decay time measurement. A digital heterodyning technique is disclosed in which a photon detector is sampled at a rate slightly faster than a digitally pulsed excitation signal. A resulting cross correlation frequency is low enough to be read by inexpensive electronics such as by a field programmable gate array. Phase information in the signal provides correlation with corresponding photon detections.
See also EP2529152B1.
Gratton E, Azartash K, Marsili L.
Method and device for tear film analysis.
Patent US8256898, 12 Sep 2012.Tear film stability has an important role in the quality of vision. A system and method for performing Fluctuation Analysis of Spatial Image Correlation (FASIC) provides for a non-invasive system and method for evaluating the dynamics of the tear film surface using spatial autocorrelation analysis. With FASIC, a series of images are obtained using illumination and a camera. The spatial autocorrelation is calculated for image frames produced by the camera. A sinusoidal background appears in this correlation together with other features. The changes in the sinusoidal background of the spatial autocorrelation is extracted and monitored over time. The spatial period of this sinusoidal background correlates with the thickness of the tear film. In this regard, one is able to derive the tear film thickness from the period of this sinusoidal background.
2009
Gratton E, Motolese G, Tahari AK.
Methods and devices for characterizing particles in clear and turbid media [continuation of US patent 7528384].
Patent US20090230324, 17 Sep 2009.The invention provides methods and devices for detecting, identifying, classifying and characterizing particles in a fluid sample. Optical analyzers are provided having a rotating and/or translating sample container for measuring the concentrations of fluorescent particles present in very low concentrations and for characterizing fluorescent particles on the basis of size, shape, diffusion constant and/or composition. Scanning optical analyzers are provided using pattern recognitions data analysis techniques and multichannel detection.
Gratton E, Motolese G, Tahari AK.
Methods and devices for characterizing particles in clear and turbid media.
Patent US7528384, 05 May 2009.The invention provides methods and devices for detecting, identifying, classifying and characterizing particles in a fluid sample. Optical analyzers are provided having a rotating and/or translating sample container for measuring the concentrations of fluorescent particles present in very low concentrations and for characterizing fluorescent particles on the basis of size, shape, diffusion constant and/or composition. Scanning optical analyzers are provided using pattern recognitions data analysis techniques and multichannel detection.
2008
Gatto R, D'Amico E, Mantulin WW, Gratton E, Charbel FT.
Optical microprobe for blood clot detection.
Patent US20080300493, 04 Dec 2008.The invention is devices and related methods for detecting blood clots in a blood vessel. An optical microprobe is configured to illuminate a blood vessel with electromagnetic radiation corresponding to the near-infrared portion of the electromagnetic spectrum. The optical microprobe has a pair of fiber optic strands configured for transmission spectroscopy to obtain the absorption spectrum generated by the components within the blood vessel. Because blood clots generate a detectable and unique spectrum, the presence or absence of the blood clot is determined by examining the blood vessel absorption spectrum. A specially-designed holder is configured to stably position the optical microprobe relative to the blood vessel and is used to facilitate precise blood clot detection along a length of blood vessel.
Gratton E, Kukreti S, Cerussi AE, Tromberg BJ.
Method and apparatus for the determination of intrinsic spectroscopic tumor markers by broadband-frequency domain technology.
Patent US20080009748, 10 Jan 2008.The illustrated embodiment is an improvement in a method of optically analyzing tissue in vivo in an individual to obtain a unique spectrum for the tissue of the individual, the improvement including the steps of optically measuring the tissue of the individual to obtain a spectrum of an optical parameter, and identifying a spectral signature specific to a metabolic or physiologic state in the tissue of the individual with a unique spectrum for the tissue by considering only the spectral differences between a first metabolic or physiologic state of the tissue of the individual and one or more other metabolic or physiologic states of the tissue of the individual such that identification of the spectral signature is self-referencing with respect to intra-individual metabolic or physiologic variations. The method also includes separating benign and malignant lesions only using the shape or a characteristic of the spectrum.
2004
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Rapid high throughput spectrometer and method [Division of US patent 6603546].
Patent US6794659, 21 Sep 2004.A fluorescence spectrometer comprises a laser and at least one beam splitter positioned to receive a light beam from the laser and to divide it into several first light beam portions. Dichroic mirrors are positioned to separately receive the first light beam portions and to reflect the beam portions at an angle to the first light beam portions. Transparent chambers are provided for holding the samples. Objective lens systems are respectively positioned in the path of the reflected beam portions to respectively focus each reflected beam portion to a point within one of the separate transparent chambers. Lenses are positioned to receive fluorescence from a sample for testing within the transparent chambers and to respectively focus the fluorescence at pin holes in opaque partitions. The lenses are positioned to receive the fluorescence, which passes back through the objective lens system and the dichroic mirror. Light detectors are each respectively positioned ... [truncated at 150 words]
2003
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Rapid high throughput spectrometer and method.
Patent US6603546, 05 Aug 2003.A fluorescence spectrometer comprises a laser and at least one beam splitter positioned to receive a light beam from the laser and to divide it into several first light beam portions. Dichroic mirrors are positioned to separately receive the first light beam portions and to reflect the beam portions at an angle to the first light beam portions. Transparent chambers are provided for holding the samples. Objective lens systems are respectively positioned in the path of the reflected beam portions to respectively focus each reflected beam portion to a point within one of the separate transparent chambers. Lenses are positioned to receive fluorescence from a sample for testing within the transparent chambers and to respectively focus the fluorescence at pin holes in opaque partitions. The lenses are positioned to receive the fluorescence, which passes back through the objective lens system and the dichroic mirror. Light detectors are each respectively positioned ... [truncated at 150 words]
2001
Franceschini MA, Fantini S, Gratton E.
Method for measuring absolute saturation of time-varying and other hemoglobin compartments.
Patent US6216021, 10 Apr 2001.The present invention involves a time-resolved measurement method for the real time, non-invasive, simultaneous measurement of time-varying and other hemoglobin compartment saturation. This capability achieves absolute pulse oximetry and oximetry for tissue, without calibration based on a population of healthy people. Calculations conducted by the invention use quantitative measurement of tissue absorption spectrum for tissue saturation, and an amplitude of absorption oscillations for the time-varying hemoglobin compartments at various wavelengths. The invention illuminates tissue and senses light at predetermined distances apart on the tissue to be measured. Intensity and phase data are acquired from source-detector pairs to calculate absolute tissue optical properties from time-resolved measurement data, namely, a reduced scattering coefficient and an absorption coefficient. To determine time-varying hemoglobin compartment saturation, an amplitude is quantitatively calculated of absorption oscillations correlating variations of an average intensity of the source and detector pair by using the time-resolved measurement data.
Gratton E, Fantini S, Franceschini MA, Mantulin WW, Barbieri BB.
Photosensor with multiple light sources.
Patent US6192261, 20 Feb 2001.The quantitative determination of various materials in highly scattering media such as living tissue may be determined in an external, photometric manner by the use of a plurality of light sources positioned at differing distances from a sensor. The light from said sources is amplitude modulated, and, in accordance with conventional frequency domain fluorometry or phosphorimetry techniques, the gain of the sensor is modulated at a frequency different from the frequency of the light modulation. Data may be acquired from each of the light sources at differing distances at a frequency which is the difference between the two frequencies described above. From these sets of data from each individual light source, curves may be constructed, and the slopes used to quantitatively determine the amount of certain materials present, for example glucose, oxyhemoglobin and deoxyhemoglobin in living tissue.
1998
Dong CY, Gratton E, So PTC.
Pump probe cross correlation fluorescence frequency domain microscope and microscopy.
Patent US5814820, 29 Sep 1998.A scanning fluorescence lifetime microscope measures modulation and phase in fluorescence emission stimulated by spatially overlapped pump and probe beams operating at different frequencies. A pump laser modulated at a first frequency is focused onto a diffraction limited spot to excite a fluorescent sample under study. Simultaneously, a probe laser modulated at a second frequency is focused onto the same spot to induce a stimulated fluorescence emission in response to the optically combined output of the pump and probe laser light. Fluorescence emitted from the sample produces a cross-correlation signal which is dependent upon the spatial overlapping of the pump and probe beams at the focal point thereby producing a beneficial axial sectioning effect. Choosing a small differency frequency between the modulation of the first and second laser sources produces a low frequency cross correlation signal even when the modulation frequencies of the pump and probe lasers are very high. ... [truncated at 150 words]
Gratton E, Fantini S, Franceschini MA, Mantulin WW, Barbieri BB.
Photosensor with multiple light sources [Continuation-in-part of US patents 5497769 and 5492118].
Patent US5772587, 30 Jun 1998.The quantitative determination of various materials in highly scattering media such as living tissue may be determined in an external, photometric manner by the use of a plurality of light sources positioned at differing distances from a sensor. The light from said sources is amplitude modulated, and, in accordance with conventional frequency domain fluorometry or phosphorimetry techniques, the gain of the sensor is modulated at a frequency different from the frequency of the light modulation. Data may be acquired from each of the light sources at differing distances at a frequency which is the difference between the two frequencies described above. From these sets of data from each individual light source, curves may be constructed, and the slopes used to quantitatively determine the amount of certain materials present, for example glucose, oxyhemoglobin and deoxyhemoglobin in living tissue.
1996
Gratton E, Fantini S, Franceschini MA, Mantulin WW, Barbieri BB.
Photosensor with multiple light sources.
Patent US5497769, 12 Mar 1996.The quantitative determination of various materials in highly scattering media such as living tissue may be determined in an external, photometric manner by the use of a plurality of light sources positioned at differing distances from a sensor. The light from said sources is amplitude modulated, and, in accordance with conventional frequency domain fluorometry or phosphorimetry techniques, the gain of the sensor is modulated at a frequency different from the frequency of the light modulation. Data may be acquired from each of the light sources at differing distances at a frequency which is the difference between the two frequencies described above. From these sets of data from each individual light source, curves may be constructed, and the slopes used to quantitatively determine the amount of certain materials present, for example oxyhemoglobin and deoxyhemoglobin in living tissue.
Gratton E, Maier JS, Franceschini MA, Fantini S, Walker SA.
Determining material concentrations in tissues.
Patent US5492118, 20 Feb 1996.The relative concentration of a material such as glucose in a turbid medium such as living tissue may determining the scattering coefficient of the light that has passed through the turbid medium; and comparing the scattering coefficient with a previous scattering coefficient determined with respect to the turbid medium.
1994
Gratton E, VandeVen MJ, Barbieri BB.
Time resolved optical array detectors and CCD cameras for frequency domain fluorometry and/or phosphorimetry.
Patent US5323010, 21 Jun 1994.An apparatus for cross-correlation frequency domain fluorometry-phosphorimetry comprises a source of electromatic radiation and means for amplitude modulating the radiation at the first frequency. The amplitude modulated radiation is directed at a sample, while an optical array detector measures the resulting luminescence of the sample. A signal is provided coherent with the amplitude modulated electromagnetic radiation signals, at a second frequency which is different from the first frequency. The apparatus has the capability for shutting off and turning on the coherent signal at the second frequency in a cycle which is at a third frequency that is different from the difference between the first and second frequencies. This produces a resultant signal at a frequency derived from the difference and the third frequency. The resultant signal, when turned on, modulates the gain of the detecting means or multiplies its output, depending upon the nature of the detecting means. The amount ... [truncated at 150 words]
1993
Feddersen BA, Gratton E, Piston DW.
Method and means for parallel frequency acquisition in frequency domain fluorometry.
Patent US5257202, 26 Oct 1993.A digital frequency domain fluorometer utilizing a computer-controlled digital data acquisition system is use for the study of fluorescence and phosphorescence phenomena in the bio-chemical, biological and bio-physics arts. The computer is used for the direct collection of data, as well as for the filtering and calculation of the phase and modulation values of the sample under study. From these values, fluorescence lifetimes and anisotropy decay times can determined. The digital data acquisition system provides for the simultaneous collection and processing of several modulation frequencies. In addition, the digital frequency domain fluorometer can utilize an array detector for detecting the modulated light from the various samples under study. The use of the array detector provides a means for independently collecting data over a large number of pixels. This configuration allows for a time resolved image to be collected at once.
Gratton E, Mantulin WW, VandeVen MJ.
Frequency domain optical imaging using diffusion of intensity modulated radiation.
Patent US5213105, 25 May 1993.Arrangements are disclosed for producing images based upon diffusional wave theory and frequency domain analysis. A medium to be imaged is illuminated with amplitude modulated radiation, and diffusional radiation transmitted or reflected by the medium is detected at a plurality of detection locations, as by a television camera. The phase and also the amplitude demodulation of the amplitude modulated diffusional radiation is detected at each detection location. A relative phase image and also a demodulation amplitude image of the medium are then generated from respectively the detected relative phase values and the detected demodulation amplitudes of the diffusional radiation at the plurality of locations. The present invention is particularly suited for medical applications for generating images of internal anatomical details of the body by using a near infrared amplitude modulated source for illumination of the body. In such medical applications, the body is illuminated with near infrared radiation having a ... [truncated at 150 words]
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High speed cross-correlation frequency domain fluorometry-phosphorimetry.
Patent US5212386, 18 May 1993.Apparatus for cross-correlation frequency domain fluorometry and/or phosphorimetry in which means are provided for sequentially performing runs of the cross correlation frequency domain fluorometry and/or phosphorimetry at sequentially differing first and second frequencies. The intensities of signal responses of the runs are detected at the respective cross-correlation frequency in each run. The detection of the signal response is prolonged in each run until an integrated signal with a specified standard deviation has been acquired at each of the differing runs. Preferably the sequential runs are automatically executed by a program. Also, the waveforms sensed by deriving the resultant signal response in each run are folded. That is: corresponding segments of the waveforms are superimposed to obtain an average waveform value for each run having an increased signal to noise ratio over the individual waveform segments. Also, preferably, a software-created variable frequency digital filter is used to filter signal responses at ... [truncated at 150 words]
1989
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Frequency domain cross-correlation fluorometry with phase-locked loop frequency synthesizers.
Patent US4840485, 20 Jun 1989.Frequency domain cross-correlation fluorometers may be improved over present designs by providing a coherent signal at one frequency to means for detecting luminescence from a sample, which is elicited by light modulated at another frequency, in which the two frequencies, obtained from a pair of phase-locked loop frequency synthesizers, are different from each other by at least 100 hertz, which is a significantly greater difference than used in corresponding prior art fluorometers. This permits the use of the phase-locked loop frequency synthesizers, rather than the currently used direct synthesis synthesizers, providing significant advantages.
