Velocity independent analyte characterization

• US 7,678,547 B2
• Filed: 10/02/2001
• Issued: 03/16/2010
• Est. Priority Date: 10/03/2000
• Status: Expired due to Fees

• Current Assignee: California Institute of Technology
• Original Assignee: California Institute of Technology
• Inventors: Eyal, Shulamit, Quake, Stephen
• Primary Examiner(s): Cook; Lisa V
• Application Number:
  US09/970,453
• Publication Number:
  US 20020123033A1
• Time in Patent Office: 3,087 Days
• Field of Search: 435/7.1, 435/7.21, 435/7.92, 436/500, 436/518
• US Class Current: 435/7.21
• CPC Class Codes: B01L 2200/0647 Handling flowable solids, e.g. microscopic beads, cells, particles
• CPC Class Codes: B01L 3/5027 by integrated microfluidic structures, i.e. dimensions of channels and chambers are such that surface tension forces are important, e.g. lab-on-a-chip B01L3/5023 takes precedence; micromixers B01F33/30; microreactors for synthesis B01J19/0093; microcapillary devices in general B81B1/00
• CPC Class Codes: F04B 19/006 Micropumps F04B43/043 and F04B43/095 take precedence
• CPC Class Codes: F04B 43/043 Micropumps
• CPC Class Codes: F04B 43/14 having plate-like flexible members
• CPC Class Codes: G01N 15/1468 with spatial resolution of the texture or inner structure of the particle
• CPC Class Codes: G01N 15/147 the analysis being performed on a sample stream
• CPC Class Codes: G01N 15/1484 microstructural devices
• CPC Class Codes: G01N 15/149 specially adapted for sorting particles, e.g. by their size or optical properties
• CPC Class Codes: G01N 2015/1006 for cytology
• CPC Class Codes: G01N 2015/1438 Using two lasers in succession
• CPC Class Codes: G01N 2030/205 Diaphragm valves, e.g. deformed member closing the passage
• CPC Class Codes: G01N 2030/322 pulse dampers
• CPC Class Codes: G01N 30/6095 Micromachined or nanomachined, e.g. micro- or nanosize
• CPC Class Codes: G01N 33/53 Immunoassay; Biospecific binding assay; Materials therefor

Abstract

The present invention provides apparatuses for determining velocity independent analyte characteristic parameters and methods for using the same. In one particular aspect, the present invention provides a velocity independent flow cytometry.

Claims

1. A method for determining a characteristic parameter of an analyte, wherein the characteristic parameter of the analyte is independent of a flow velocity of the analyte, but a measurement of the characteristic parameter of the analyte is capable of being influenced by or dependent on the velocity of the analyte, said method comprising:

(a) transporting a fluid medium comprising the analyte from a first position to a second position of a fluid flow channel of a fluidic device;

(b) measuring the characteristic parameter of the analyte within the fluid flow channel at a plurality of different detection zones separated along a flow path of the analyte in between the first and the second positions;

(c) determining a velocity dependence of the measurement of the characteristic parameter; and

(d) determining the characteristic parameter of the analyte independent of the flow velocity of the analyte by using the measurements of the characteristic parameter of step (b) and normalizing the measurements of the characteristic parameter by substantially eliminating the velocity dependence of the measurements of the characteristic parameter.

2. The method of claim 1, wherein said fluidic device is a microfluidic device.

3. The method of claim 2, wherein transporting the fluid medium comprises transporting the fluid medium with a peristaltic pump or by electroosmosis.

4. The method of claim 1, wherein the characteristic parameter of the analyte is measured in step (b) with a laser beam guiding device that comprises an acousto-optic modulator.

5. The method of claim 1, wherein the analyte is a cell, an oligonucleotide or an organic compound.

6. The method of claim 5, wherein the analyte is a cell and said method is used for cell sorting.

7. The method of claim 5, wherein the analyte is an oligonucleotide and said method comprises determining the number of nucleotides in the oligonucleotide.

8. The method of claim 7, wherein said step of determining the number of nucleotides in the oligonucleotide comprises:

(A) attaching a fluorescent molecule to the oligonucleotide to produce a modified oligonucleotide prior to measuring velocity independent characteristic parameter of the modified oligonucleotide, wherein said characteristic parameter is an integrated fluorescent peak area of said modified oligonucleotide; and

(B) determining the number of nucleotides in the oligonucleotide by comparing the velocity independent integrated fluorescence peak area of the modified oligonucleotide with a velocity independent fluorescence peak area of a standard oligonucleotide, wherein the velocity independent fluorescence peak area of the standard oligonucleotide has been calibrated to the number of nucleotides present the standard oligonucleotide.