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Dysfunctional hemoglobin derivatives, such as carboxyhemoglobin and methemoglobin, do not participate in vital oxygen transport and are therefore of great importance in clinical diagnostics. The optical determination of their concentrations in whole blood is difficult due to the strong light scattering processes, which depend on numerous parameters unknown at the time of measurement. For this reason, the erythrocytes are usually destroyed prior analysis. This can be an exclusion criterion for subsequent analyses. We present a new method for the determination of hemoglobin derivatives in unaltered whole blood using Support Vector regression (SVR) in the spectral range from 450 to 700 nm. Diffuse reflection as well as diffuse, unscattered and total transmission of 358 blood samples were measured using a double integrating sphere setup and used to train SVR models that predict hemoglobin derivative concentrations in unknown samples. The proportions of the hemoglobin derivatives as well as the hematocrit and osmotic concentration of the samples were adjusted using a tonometer and buffer solutions. 34 separate whole blood samples were used as test set. Overall R2 greater than 0.97 and mean absolute errors smaller than 2.03 % solely on total transmission spectra indicate that SVR is an appropriate method.
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