Effect of Selenium Nanoparticle Size on IL-6 Detection Sensitivity in a Lateral Flow Device

Area of Science:

• Nanotechnology
• Biomedical Diagnostics
• Immunochemistry

Background:

• Sepsis diagnosis is critical but challenged by slow, centralized testing.
• Current point-of-care (POC) sepsis detection methods, like lateral flow devices (LFDs), lack sufficient sensitivity.
• Interleukin-6 (IL-6) is a key biomarker for sepsis detection.

Purpose of the Study:

• To develop and evaluate larger selenium nanoparticles (SeNPs) for enhanced sensitivity in LFD-based sepsis detection.
• To compare the performance of SeNPs with commercial gold nanoparticles (AuNPs) in detecting the sepsis biomarker IL-6.
• To investigate the impact of SeNP size on LFD assay sensitivity.

Main Methods:

• Fabrication of LFDs utilizing 150-310 nm sized selenium nanoparticles (SeNPs).
• Comparison of SeNP-based LFDs against commercial 40 nm gold nanoparticle (AuNP) LFDs.
• Quantification of the limit of detection (LOD) for IL-6 using both SeNP and AuNP LFDs.

Main Results:

• SeNP-based LFDs demonstrated a lower LOD for IL-6 (0.1 ng/mL) compared to AuNP-based LFDs (1 ng/mL).
• Larger SeNPs (150-310 nm) achieved higher sensitivity than standard 40 nm AuNPs.
• A trade-off was observed between sensitivity and test line visual intensity with SeNPs.

Conclusions:

• Larger selenium nanoparticles are viable and potentially superior labels for LFDs in sepsis diagnostics.
• SeNPs offer a promising avenue for improving the sensitivity of POC sepsis detection assays.
• This study represents the first use of larger SeNPs (>100 nm) in LFDs for biomarker detection and compares their size-dependent effects on sensitivity.