Analyte system and method for determining hemoglobin parameters in whole blood

Inventors

Cafferty, Michael S. • Cionek, Scott P.

Assignees

Nova Biomedical Corp

Abstract

A method of measuring whole-blood hemoglobin parameters includes providing a LED light source, guiding light having the spectral range from the LED light source along an optical path, providing a cuvette module with a sample receiving chamber, providing a pair of first and second optical diffusers disposed in the optical path where the cuvette module is disposed between the pair of first and second optical diffusers, guiding light from the cuvette module into an optical spectrometer, and processing an electrical signal from the spectrometer into an output signal useable for displaying and reporting hemoglobin parameter values and/or total bilirubin parameter values of the sample of whole blood.

Core Innovation

The invention relates to a method of measuring hemoglobin parameters in a whole blood sample using optical absorbance. The method includes measuring and recording a transmitted light intensity scan over a plurality of wavelengths in a measurement range by transmitting light through a cuvette module having an optical path with a known optical path length, where the cuvette module is filled with a transparent fluid, and then measuring and recording a transmitted light intensity scan over the plurality of wavelengths for a second transmission through the cuvette module when it is filled with a whole blood sample having the same known optical path length.

For each measuring and recording step of the transparent fluid and the whole blood sample, the transmitted light is diffusing and circularly polarizing before transmission through the cuvette module, and the transmitted light emitting from the cuvette module is diffused before determining a spectral absorbance at each wavelength. The spectral absorbance at each wavelength is determined based on a ratio of the transmitted light intensity scan of the whole blood sample to the transmitted light intensity scan of the transparent fluid, and a spectrometer is used in determining the spectral absorbance.

The method further correlates the spectral absorbance at each wavelength of the plurality of wavelengths to hemoglobin parameter values and/or bilirubin parameter values using a computational mapping function. The correlating targets can include total hemoglobin, carboxyhemoglobin, deoxyhemoglobin, and methemoglobin as hemoglobin parameter values.

The invention also includes refinements directed to measurement stability and implementation, including thermal-drift compensation by insulating the spectrometer, controlled heating, and/or using a thermal-compensating lens mounting. Known cuvette optical path length is handled by selecting a cuvette module with an electronic chip that stores the measured optical path length electronically, and the correlating step can employ a kernel-based orthogonal projection computational mapping function to a latent structures function.

Claims Coverage

The independent claim contains three main inventive aspects: two scan measurements through a cuvette module with a known optical path length using a transparent-fluid/whole-blood ratio, specific optical conditioning with diffusing and circular polarization to determine wavelength-by-wavelength spectral absorbance, and correlating that spectral absorbance to hemoglobin and/or bilirubin parameter values using a computational mapping function.

Overall, the claim coverage centers on producing wavelength-resolved spectral absorbance from ratioed transmitted-light scans through a cuvette with a known optical path length, using diffusing and circularly polarized light conditioning, and then correlating that spectral absorbance to hemoglobin and/or bilirubin parameter values via a computational mapping function.

Stated Advantages

Documented Applications