A Highly Sensitive Lateral-Flow Strip Using Latex Microspheres to Detect NGAL in Urine Samples

Area of Science:

• Biomarker Discovery
• Diagnostic Assay Development
• Point-of-Care Testing

Background:

• Global increase in kidney disease incidence necessitates early detection methods.
• Neutrophil Gelatinase-Associated Lipocalin (NGAL) is a promising biomarker for acute kidney injury (AKI) and chronic kidney disease (CKD).
• Existing diagnostic methods may lack speed and cost-effectiveness for widespread early screening.

Purpose of the Study:

• To develop a rapid, point-of-care lateral flow strip (LFS) for detecting urinary NGAL.
• To utilize latex microspheres (LMs) as a visual label in a lateral flow immunoassay (LFIA).
• To evaluate the performance and stability of the developed NGAL LFS for clinical utility.

Main Methods:

• Development of a lateral flow immunoassay (LFIA) incorporating latex microspheres (LMs) for NGAL detection.
• Testing the LFS for sensitivity, specificity, and interference using urine samples.
• Comparison of LFS results with the established enzyme-linked immunosorbent assay (ELISA) method.

Main Results:

• The developed LMs-LFS detected urinary NGAL within 15 minutes with high specificity.
• Visual limit of detection (vLOD) was 18.75 ng/mL, and the limit of detection (LOD) was 1.65 ng/mL.
• High correlation observed between LMs-LFS and ELISA (R² = 0.973, n=60), with good room-temperature stability (≥6 months).

Conclusions:

• The developed latex microsphere-based lateral flow strip (LMs-LFS) is a rapid and sensitive tool for urinary NGAL detection.
• This assay demonstrates potential for point-of-care diagnosis and monitoring of kidney disorders.
• The LMs-LFS offers a stable, specific, and cost-effective alternative for renal health assessment.