Molecular imaging

• US 6,103,533 A
• Filed: 03/26/1998
• Issued: 08/15/2000
• Est. Priority Date: 05/10/1995
• Status: Expired due to Term

• Current Assignee: deltaDOT Limited
• Original Assignee: Imperial College of Science Technology & Medicine (Imperial College London)
• Inventors: Colling, David John, Hassard, John Francis
• Primary Examiner(s): Warden, Sr., Robert J.
• Assistant Examiner(s): ALDAG, ANDREW J
• Application Number:
  US08/952,032
• Time in Patent Office: 873 Days
• Field of Search: 436/57, 436/85, 436/94, 436/161, 436/162, 436/164, 436/172, 422/71, 422/82.05, 422/82.09, 204/450, 204/451, 204/466, 204/461
• US Class Current: 436/57
• CPC Class Codes: G01N 27/44717 Arrangements for investigating the separated zones, e.g. localising zones
• CPC Class Codes: G01N 27/44721 by optical means

Abstract

A method of identifying individual substances within a mixture of substances comprises causing the mixture to travel past a spaced series of detectors, each being arranged to produce a signal representative of a characteristic of the mixture as it passes, repeatedly measuring the signals from each detector at a plurality of times, transforming into velocity space, and identifying individual substances within the mixture according to the peaks they create in velocity space.

Claims

1. A method of identifying individual substances within a mixture of substances comprising the steps of:

(a) causing the mixture to travel past a spaced plurality of detectors, each detector I_k being arranged to produce a signal S_k representative of a characteristic of the mixture as the mixture passes the detector I_k ;

(b) repeatedly measuring the signal S_k (t) at each detector I_k at a plurality of times t=t₁, t₂, t₃ . . . ;

(c) associating each signal S_k (t) with a respective nominal velocity V_k (t), wherein V_k (t) is calculated as that constant velocity which a substance traveling within the mixture would need to reach the detector I_k at time t;

(d) grouping the signals S_k (t) by nominal velocity V_k (t); and

,

(e) identifying individual substances within the mixture according to peaks within a histogram of the grouped signals.

2. The method as defined in claim 1 wherein all the signals S_k (t) are collected in a first step and are then grouped in a subsequent step.

3. The method as defined claim 1 wherein the signals S_k (t) are grouped as the signals are collected.

4. The method as defined in claim 1 wherein the nominal velocity V_k (t) is determined from a knowledge of the distance travelled from an origin point to the detector I_k, and the time elapsed.

5. The method as defined in claim 4 wherein the nominal velocity is calculated as Z_k /t, where Z_k is the distance from the origin to the detector I_k, and t is the time elapsed.

6. The method as defined in claim 1 wherein each signal S_k (t) is allocated to one of a plurality of histogram bins according to its associated nominal velocity V_k (t), the content of each histogram bin being determined by summing all of the signals which have been allocated to it.

7. The method as defined in claim 1 wherein the signals S_k are representative of the diminution of light received by the detectors as a result of light absorption by the substances to be identified.

8. The method as defined in claim 1 wherein the signals S_k are representative of emissions received from the substances to be identified.

9. The method as defined in claim 8 wherein the emissions are radioactive emissions.

10. The method as defined in claim 8 wherein the emissions are UV emissions.

11. The method as defined in claim 1 wherein the proportions of the individual substances within the mixture are determined according to the relative sizes of the peaks within the histogram of grouped signals.