Background:This study was planned to assess the accuracy and comparability of two commercially available,laboratory-based SARS-CoV-2(severe acute respiratory syndrome)antigen(Ag)immunoassays.Methods:We studied a cohor...Background:This study was planned to assess the accuracy and comparability of two commercially available,laboratory-based SARS-CoV-2(severe acute respiratory syndrome)antigen(Ag)immunoassays.Methods:We studied a cohort of subjects with acute SARS-CoV-2 infection,from whom a nasopharyngeal swab was taken and tested with a molecular assay(Altona Diagnostics RealStar SARS-CoV-2 RT-PCR Kit)and two laboratory-based,fully automated SARS-CoV-2 Ag immunoassays(Fujirebio Lumipulse G SARS-CoV-2 Ag and Roche Elecsys SARS-CoV-2 Ag).Results:The final population consisted in 93 subjects testing positive for SARS-CoV-2 RNA,34 with cycle threshold(Ct)values<29.5.The results of the two SARS-CoV-2 Ag immunoassays were significantly intercorrelated(r=0.77;P<0.001)in the entire cohort,though such correlation considerably improved in patients with high viral load(cycle threshold values<29.5:r=0.96;P<0.001).The accuracy for identifying samples with high viral load was excellent for both Lumipulse G SARS-CoV-2 Ag(AUC,0.99;P<0.001)and Elecsys SARS-CoV-2 Ag(AUC,0.99;P<0.001),with best cut-offs of 2.03 ng/mL for Lumipulse G SARS-CoV-2 Ag(1.00 sensitivity and 0.88 specificity)and 0.70 COI for Elecsys SARS-CoV-2 Ag(1.00 sensitivity and 0.80 specificity),respectively.Conclusion:The results of this study provide valuable support to usability of fully-automated,rapid,high throughput and accurate SARS-CoV-2 Ag immunoassays for complementing molecular assays.展开更多
New reagents for immunofluorescence analysis of carbazole series containing fluorinated β-dicarbonyl fragments and carboxylic substituent groups separated by spacers of different lengths from the light-gathering carb...New reagents for immunofluorescence analysis of carbazole series containing fluorinated β-dicarbonyl fragments and carboxylic substituent groups separated by spacers of different lengths from the light-gathering carbazole scaffold have been developed. The markers in complex with Eu<sup>3+</sup> ions possess stability in the aqueous phase, intense and prolonged luminescence (τ 550 - 570 μs) with characteristic emission maxima in the region of 615 nm and excitation wavelengths in the region of 380 - 390 nm, which distinguishes them from most of the analogs used. In the study of marker conjugation with streptavidin, a reagent containing 4 - 5 europium labeling complexes based on spacer-containing carbazole tetraketone was obtained. The marker-doped silicate nanoparticles exhibit intense and long-lived luminescence in the characteristic region.展开更多
文摘Background:This study was planned to assess the accuracy and comparability of two commercially available,laboratory-based SARS-CoV-2(severe acute respiratory syndrome)antigen(Ag)immunoassays.Methods:We studied a cohort of subjects with acute SARS-CoV-2 infection,from whom a nasopharyngeal swab was taken and tested with a molecular assay(Altona Diagnostics RealStar SARS-CoV-2 RT-PCR Kit)and two laboratory-based,fully automated SARS-CoV-2 Ag immunoassays(Fujirebio Lumipulse G SARS-CoV-2 Ag and Roche Elecsys SARS-CoV-2 Ag).Results:The final population consisted in 93 subjects testing positive for SARS-CoV-2 RNA,34 with cycle threshold(Ct)values<29.5.The results of the two SARS-CoV-2 Ag immunoassays were significantly intercorrelated(r=0.77;P<0.001)in the entire cohort,though such correlation considerably improved in patients with high viral load(cycle threshold values<29.5:r=0.96;P<0.001).The accuracy for identifying samples with high viral load was excellent for both Lumipulse G SARS-CoV-2 Ag(AUC,0.99;P<0.001)and Elecsys SARS-CoV-2 Ag(AUC,0.99;P<0.001),with best cut-offs of 2.03 ng/mL for Lumipulse G SARS-CoV-2 Ag(1.00 sensitivity and 0.88 specificity)and 0.70 COI for Elecsys SARS-CoV-2 Ag(1.00 sensitivity and 0.80 specificity),respectively.Conclusion:The results of this study provide valuable support to usability of fully-automated,rapid,high throughput and accurate SARS-CoV-2 Ag immunoassays for complementing molecular assays.
文摘New reagents for immunofluorescence analysis of carbazole series containing fluorinated β-dicarbonyl fragments and carboxylic substituent groups separated by spacers of different lengths from the light-gathering carbazole scaffold have been developed. The markers in complex with Eu<sup>3+</sup> ions possess stability in the aqueous phase, intense and prolonged luminescence (τ 550 - 570 μs) with characteristic emission maxima in the region of 615 nm and excitation wavelengths in the region of 380 - 390 nm, which distinguishes them from most of the analogs used. In the study of marker conjugation with streptavidin, a reagent containing 4 - 5 europium labeling complexes based on spacer-containing carbazole tetraketone was obtained. The marker-doped silicate nanoparticles exhibit intense and long-lived luminescence in the characteristic region.
