Many quantitative and semi-quantitative lateral flow (LF) assays have been introduced for clinical analytes such as biomarkers for cancer or acute myocardial infarction (AMI). Different detection technologies involving quantitative analyzing devices have been reported to have sufficient analytical sensitivity and quantification capability for clinical point-of-care tests. Fluorescence-based detection technologies such as quantum dots, Eu(III)-nanoparticles and photon-upconverting nanoparticles (UCNPs) have been introduced as promising solutions for point-of-care devices because of their high detectability by optical sensors. Lateral flow assays can be used for various sample types, e.g. urine, saliva, cerebrospinal fluid, and blood. This study focuses on the properties of serum and plasma because of their relevance in cancer- and AMI-diagnostics. The limit of detection was compared in LF-assays having Eu(III)-nanoparticles or UCNPs as reporters and the antibody configurations for two different analytes (PSA and cTnI). The results indicate significant effect of anticoagulants in venipuncture tubes. The samples in K3EDTA-tubes resulted in significant interference by decreased reporter particle mobility, and thus the limit of detection was up to eight folds less sensitive compared to serum sample. Despite the matrix interference the cTnI-assay with UCNP-reporters a limit of detection of 41 ng/L with serum and 66 ng/L with Li-heparin sample was obtained.