In 2012, Leipzig University Hospital introduced a special quality assurance method for MELD diagnostics (Model of End-Stage Liver Disease). MELD is required for patients with liver cirrhosis eligible for a liver transplant at the time of initial diagnosis as well as in follow-up and progress examinations. As part of the quality assurance process, serum retention samples are taken from routine diagnostics and stored at −20 °C. We analyzed 330 of these serum samples using the Thermo Scientific DXR 3 SmartRaman Spectrometer (Thermo Scientific Waltham, MA, USA).
For the measurements, 50 µL of each sample was placed on a glass cover slip. The samples were measured using a 785 nm laser with a power of 150 mW. A two-cycle loop was used for the automatic measurement. The first loop included three sets with an exposure time of 10 s per set, and the second loop included two sets with an exposure time of 30 s for each set. Subsequently, each set was saved separately for individual analysis. We measured each sample on different days over the course of one week.Table 3 shows the storage conditions of the sample over the week. Table 4 describes the compilation of patients. Figure 7 shows the collected spectra.
For the measurements, 50 µL of each sample was placed on a glass cover slip. The samples were measured using a 785 nm laser with a power of 150 mW. A two-cycle loop was used for the automatic measurement. The first loop included three sets with an exposure time of 10 s per set, and the second loop included two sets with an exposure time of 30 s for each set. Subsequently, each set was saved separately for individual analysis. We measured each sample on different days over the course of one week.