Time-resolved laser-induced fluorescence spectroscopy systems and uses thereof

Patent metadata

Field	Value
Publication number	US-2016003742-A1
Application number	US-201414776086-A
Country	US
Kind code	A1
Filing date	Mar 17, 2014
Priority date	Mar 15, 2013
Publication date	Jan 7, 2016
Grant date	—

Abstract

The invention provides systems for characterizing a biological sample by analyzing emission of fluorescent light from the biological sample upon excitation and methods for using the same. The system includes a laser source, collection fibers, a demultiplexer and an optical delay device. All references cited herein are incorporated by reference in their entirety as though fully set forth. Unless defined otherwise, technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs.

First claim

1 . A system for characterizing a biological sample by analyzing emission of fluorescent light from the biological sample upon excitation comprising:
(i) a laser source connected to a biological sample via excitation fibers (ExF), wherein the laser is configured to radiate the biological sample with a laser pulse at a predetermined wavelength to cause the biological to produce a responsive fluorescence signal; (ii) collection fibers (CF), wherein the CF collect the fluorescence signal from the sample, and relays the signal to a demultiplexer; (iii) a demultiplexer comprising wavelength splitting filters so as to split the signal from the CF at pre-determined wavelengths to obtain spectral bands; and (iv) an optical delay device.

2 . The system of claim 1 , further comprising a photomultiplier tube comprising a preamplifier so as to amplify the signal after the signal has passed through the photomultiplier tube before the signal is digitized.

3 . The system of claim 2 , further comprising a digitizer so as to digitize the signal received from the photomultiplier tube and a computer system to process and display the signal.

4 . The system of claim 1 , wherein the optical delay device is adapted to couple the spectral bands from the demultiplexer into the delay device, allow the spectral bands to travel through the delay device and introduce a controlled time delay as the spectral bands travel through delay device, so as to capture multiple wavelengths in a single shot.

5 . The system of claim 1 , wherein the collection fibers form a single bundle.

6 . The system of claim 1 , wherein the demultiplexer splits the incoming signal at wavelengths of 355 nm (less than 360), 365-410 nm, 410-450 nm, 450-480 nm, 500-560 nm, 560-600 nm and greater than 600 nm.

7 . A method for characterizing a biological sample by analyzing emission of a fluorescence signal from the biological sample upon excitation comprising:
(i) radiating the biological sample with a laser pulse at a predetermined wavelength to cause the biological to produce a responsive fluorescence signal; (ii) collecting the fluorescence signal from the sample; (iii) splitting the signal at predetermined wavelengths to obtain spectral bands; (iv) passing the spectral bands through a time-delay mechanism; (v) obtaining the time-delayed spectral bands; and (vi) processing the time-delayed spectral band signal.

8 . The method of claim 7 , wherein processing the signal comprises passing the signal through a digitizer so as to digitize the signal received from a photomultiplier tube to a computer system to process and display the signal.

9 . The method of claim 7 , wherein splitting the signal comprises splitting the incoming signal with a demultiplexer at wavelengths of 355 nm (less than 365 nm), 365-410, 410-450 nm, 450-480 nm, 500-560 nm, 560-600 nm and greater than 600 nm.

10 . The method of claim 7 , wherein the fluorescence signal is emitted by a biomolecule.

11 . The method of claim 10 , wherein the biomolecule is any one or more of PLP-GAD (pyridoxal-5′-phosphate (PLP) glutamic acid decarboxylase (GAD)), bound NADH, free NADH, flavin mononucleotide (FMN) riboflavin, flavin adenine dinucleotide (FAD) riboflavin, lipopigments, endogenous porphyrins or a combination thereof.

12 . A method for determining tissue viability comprising analyzing emission of fluorescence signals from biomolecules in the tissue by the method of claim 7 , wherein an increase in fluorescence of the biomolecule in the subject relative to a normal subject is indicative of poor tissue viability.

13 . A method for continuously monitoring cellular metabolism comprising analyzing emission of a fluorescence signal by the method of claim 7 .

14 . A method for determining drug or metabolite level in plasma comprising analyzing emission of a fluorescence signal from a biomolecule by the method of claim 7 .

15 . The method of claim 14 , wherein the biomolecule is NADH.

16 . The method of claim 15 , wherein NADH is in free form, bound form or a combination thereof.

Assignees

• Cedars Sinai Medical Center

Inventors

• Butte Pramod
• Lapchak Paul
• Kittle David Scott

Classifications

• G01N2021/6484

  Optical fibres · CPC title

• G01N21/6408 Primary

  with measurement of decay time, time resolved fluorescence · CPC title

• G01J3/0218

  using optical fibers · CPC title

• G01J3/4406

  Fluorescence spectrometry · CPC title

• G01N21/6402

  Atomic fluorescence; Laser induced fluorescence · CPC title