Accurate neuron-specific enolase quantification via amino acid analysis-IDMS: enabling magnetic nanoparticle-based...

Area of Science:

• Biochemistry
• Analytical Chemistry
• Biomarker Detection

Background:

• Neuron-specific enolase (NSE) is a crucial biomarker for neurological conditions and certain cancers.
• Accurate quantification of NSE is essential for reliable clinical diagnostics.
• Existing detection methods may lack the necessary precision or point-of-care accessibility.

Purpose of the Study:

• To develop and validate an accurate method for quantifying recombinant neuron-specific enolase (NSE).
• To utilize the quantified NSE as a calibrator for a novel point-of-care diagnostic assay.
• To assess the performance of a magnetic nanoparticle-based immunochromatographic assay (MNP-ICA) for serum NSE detection.

Main Methods:

• Quantification of recombinant NSE using isotope dilution liquid chromatography-mass spectrometry (IDMS) with amino acid analysis.
• Traceability of measurements to SI-moles for high accuracy.
• Development and optimization of a magnetic nanoparticle-based immunochromatographic assay (MNP-ICA) using the quantified NSE as a calibrator.

Main Results:

• Accurate NSE concentration determined as (0.0924 ± 0.0074) mg∙mL⁻¹, traceable to SI-moles.
• The MNP-ICA demonstrated a linear range of 2.5–80.0 ng∙mL⁻¹ with a low detection limit of 2.09 ng∙mL⁻¹.
• High precision (RSD < 4.5% intra-assay, < 11.6% inter-assay) and recovery (88.8–107.3%) were achieved, with results correlating well to a commercial ELISA kit.

Conclusions:

• The IDMS method provides accurate, SI-traceable quantification of recombinant NSE.
• The developed MNP-ICA is a reliable and sensitive tool for point-of-care detection of NSE in human serum.
• The validated MNP-ICA holds promise for clinical diagnostics and monitoring of NSE-related conditions.