LSPR-Based Aptasensor for Rapid Urinary Detection of NT-proBNP

Area of Science:

• Biomedical Engineering
• Nanotechnology
• Clinical Diagnostics

Background:

• N-terminal pro-brain natriuretic peptide (NT-proBNP) is a key biomarker for myocardial stress and cardiovascular disease.
• Current diagnostic methods for NT-proBNP can be time-consuming or require specialized equipment.
• Urine offers a non-invasive biofluid for biomarker detection, but challenges remain in assay development.

Purpose of the Study:

• To develop a rapid and straightforward localized surface plasmon resonance (LSPR)-based assay for detecting NT-proBNP in urine.
• To evaluate the assay's performance, including its limit of detection and linear range.
• To assess the potential clinical applicability of the assay for diagnosing cardiovascular disease.

Main Methods:

• Utilized citrate-capped gold nanoparticles (AuNPs) and an NT-proBNP-specific aptamer for the LSPR assay.
• Developed a detection mechanism based on aptamer interaction with NT-proBNP and subsequent NaCl-induced AuNP aggregation.
• Measured changes in absorbance at specific wavelengths (A521 and A750) to quantify NT-proBNP concentration.

Main Results:

• The LSPR assay achieved rapid detection of NT-proBNP in urine within approximately 25 minutes.
• Demonstrated a limit of detection (LOD) of 0.417 µg·L⁻¹ and a detection range of 0.589-6 µg·L⁻¹ in diluted urine.
• Successfully detected NT-proBNP in urine samples from preterm infants with cardiovascular disease, showing high recovery rates (92.3-116.3%).

Conclusions:

• The developed LSPR-based assay is a sensitive and rapid tool for NT-proBNP detection in urine.
• The assay shows potential for the non-invasive diagnosis and monitoring of cardiovascular disease.
• Further research may be needed to overcome limitations observed with other biofluids like saliva.