Sensitive and rapid method for detection of low levels of lal-reactive substances

Patent metadata

Field	Value
Publication number	US-2018156795-A1
Application number	US-201815884347-A
Country	US
Kind code	A1
Filing date	Jan 30, 2018
Priority date	Oct 8, 2012
Publication date	Jun 7, 2018
Grant date	—

Abstract

Methods and systems for measuring the concentration of LAL-reactive substances in fluid samples is provided. They include contacting an aqueous sample with a detection reagent to form a prepared sample. A physical property of the prepared sample may be measured to obtain at least one sample measurement characteristic of the prepared sample. Curve fitting may then be used to forecast a concentration of the LAL-reactive substance the aqueous sample will have at a specified time in the future based on the sample measurement and a correlation developed between at least one standard measurement of a physical quality of a solution with a known concentration of a LAL-reactive substance therein. The quality of the sample measurement may be validated using historical data and/or the standard measurement.

First claim

What is claimed is:

1 . A method for measuring concentration of a LAL-reactive substance in an aqueous sample, said method comprising:
(a) contacting said aqueous sample with a detection reagent to form a prepared sample; (b) measuring a physical property of said prepared sample to obtain at least one sample measurement characteristic of said prepared sample; and (c) using curve-fitting to:
forecast a concentration of said LAL-reactive substance said aqueous sample will have at a specified time in the future based on said sample measurement and a correlation developed between at least one standard measurement of a physical property of a solution with a known concentration of a LAL-reactive substance therein; and
validate the quality of said sample measurement using historical data and/or said standard measurement;
wherein at least one apparent time delay of a cascade initiation of a reaction is included as a variable in the curve-fitting step.

2 . The method of claim 1 , wherein said physical property is an optical property selected from the group consisting of transmittance, absorbance, turbidity, light scattering, optical density, color, color value, hue, spectrum, chemiluminescence, fluorescence, magnetic resonance of absorbance over time, time to a fixed change in absorbance, maximum slope of absorbance over time, and absorbance after a fixed time.

3 . The method of claim 1 , wherein said physical property is a non-linear property, said non-linear property selected from the group consisting of reaction kinetics of said reaction and said quality of said sample measurement is validated using said non-linear property.

4 . The method of claim 3 , wherein said reaction is selected from the group consisting of an endotoxin reaction, a glucan reaction, and a combination thereof.

5 . A method for measuring concentration of a LAL-reactive substance in an aqueous sample, said method comprising:
(a) contacting said aqueous sample with a detection reagent to form a prepared sample; (b) measuring a physical property of said prepared sample to obtain at least two sample measurements characteristic of said prepared sample; and (c) forecasting a concentration of said LAL-reactive substance said aqueous sample will have at a specified time in the future based on said sample measurements and a correlation developed between the non-linear behavior of at least three standard measurements of a physical property of a solution with a known concentration of a LAL-reactive substance therein; wherein at least one apparent time delay of a cascade initiation of a reaction between the detection reagent and LAL-reactive substance is included as a variable in the forecasting step.

6 . The method of claim 5 , wherein said physical property is an optical property selected from the group consisting of transmittance, absorbance, turbidity, light scattering, optical density, color, color value, hue, spectrum, chemiluminescence, fluorescence, magnetic resonance of absorbance over time, time to a fixed change in absorbance, maximum slope of absorbance over time, and absorbance after a fixed time.

7 . The method of claim 5 , wherein said physical property is a non-linear property, said non-linear property based on known reaction kinetics of the reaction between the detection reagent and LAL-reactive substance.

8 . The method of claim 7 , wherein said reaction is selected from the group consisting of an endotoxin reaction, a glucan reaction, and a combination thereof.

Assignees

• Gen Electric

Inventors

• Melanson Paul Charles
• Sundaresan Vidyasankar
• Godec Richard Douglas
• Deng Shouquan

Classifications

• G01N33/56911 Primary

  Bacteria · CPC title

• B01L2300/0864

  comprising only one inlet and multiple receiving wells, e.g. for separation, splitting · CPC title

• B01L3/5027 Primary

  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 · CPC title

• G01N33/579 Primary

  involving limulus lysate · CPC title

• B01L2300/087

  Multiple sequential chambers · CPC title