Development and application of a novel aldehyde nanoparticle-based amplified luminescent proximity homogeneous assay for rapid quantitation of pancreatic stone protein

Clin Chim Acta. 2022 Oct 1:535:120-130. doi: 10.1016/j.cca.2022.08.020. Epub 2022 Aug 27.

Abstract

Background: Timely diagnosis of bacterial infections is important to prevent sepsis. Classical infection biomarkers have some flaws, and common detection methods are time-consuming. Thus, we aimed to establish an efficient detection method that precisely detects pancreatic stone protein (PSP) in human plasma for the timely diagnosis of bacterial infections.

Methods: Based on the novel amplified luminescent proximity homogeneous assay (AlphaLISA) method, donor and acceptor beads modified with aldehyde groups were directly coupled to the anti-PSP antibodies. PSP was quickly detected by a double-antibody sandwich method. Plasma samples from healthy individuals, bacterially infected patients, and acute-phase response patients were tested.

Results: The detection time of the developed method is only 5 min. The results of PSP-AlphaLISA and time-resolved fluorescence were consistent (ρ = 0.9722). The plasma PSP levels of patients with bacterial infection were significantly higher than those of acute-phase response patients and healthy individuals (P < 0.05). PSP levels in patients with bacterial infection with sepsis were significantly higher than those in patients with bacterial infection without sepsis (P < 0.05).

Conclusions: The PSP-AlphaLISA exhibited excellent performance and may be applied to the differential diagnosis between bacterial infection and sepsis in patients without interference from patients with acute-phase response.

Keywords: Amplified luminescent proximity homogeneous assay; Bacterial infection; Pancreatic stone protein; Sepsis.