Back to results
US 2014/0192342 A1Published application
Method and system for determining the concentration of substances in body fluids
AssigneeSiemens Healthcare Diagnostics Products GmbH
InventorsKarl Sass, Dirk Greis, Michael Noah, Christian Ueckermann
Life of this patent
Estimating the term…
Abstract
The invention relates to a method for the spectrophotometric determination of the concentration of multiple substances, preferably bilirubin, haemoglobin and lipids, in a sample of body fluid.
Claims15
A method for determining the concentrations of lipids and at least one further substance in a body fluid sample, comprising the steps of:
- a) irradiating light through the body fluid sample at a multiplicity of wavelengths and
- b) capturing a multiplicity of measured values of the absorbance of the body fluid sample at the multiplicity of wavelengths;
- characterized by the steps of:
- c) capturing a first measured value at a first wavelength at which the absorbance not caused by lipids is negligible, and determining the concentration of the lipids by dividing the measured value by the extinction coefficient specific for lipids;
- d) calculating a power-function approximation curve of the form
- E(λ)=p·λ−q
- for the absorbance of the lipids on the basis of the first measured value by determining the factor p at predetermined exponent q;
- e) determining a first approximate value of the concentration of the second substance on the basis of a second measured value and values of the approximation curve at a second wavelength.
5 more elements
A system for determining the concentrations of substances in a body fluid sample, comprising:
- i. a measurement device designed for irradiating light beams having a multiplicity of wavelengths through a body fluid sample, and for capturing a multiplicity of measured values of the absorbance of the body fluid sample at the multiplicity of wavelengths;
- and
- ii. a calculation device designed for calculating a power-function approximation curve of the form
- E(λ)=p·λ−q
- for the absorbance of the lipids on the basis of a first measured value by determining the factor p at predetermined exponent q at a first wavelength at which the absorbance not caused by lipids is negligible, and for determining a first approximate value of the concentration of a second substance on the basis of a second measured value and values of the approximation curve at a second wavelength.
2 more elements
Dependencies are inferred from the claim text.