Three types of samples were examined, including artificial serum (provided by Sigma-Aldrich, Warsaw, Poland), whole blood samples obtained from anonymous donors at a blood center in Warsaw, Poland, and blood plasma derived from the same whole blood samples (for details on the preparation process, please see the previous report ). Artificial serum was diluted to 1 mg mL -1 . The prepared artificial serum and plasma samples were subsequently spiked with varying CRP concentrations ranging from 10 ng mL -1 to 100 μg mL -1 . Blood samples were used without any preparation process. The recovery efficacy of the spiked CRP in artificial serum, plasma, and whole blood was calculated to assess the accuracy of the detection process.