Enhancing RBP4 protein detection in clinical urine samples with solid-state nanopores through optimized sandwich...

Area of Science:

• Biomolecular Engineering
• Nanotechnology
• Clinical Diagnostics

Background:

• Nanopore technology offers single-molecule sensing via ion current monitoring, but protein detection in clinical samples is hindered by low signal-to-noise ratios (SNR) and capture rates.
• The complex structure of proteins presents challenges for accurate analysis using current nanopore methods.

Purpose of the Study:

• To develop an enhanced nanopore sensing strategy for sensitive and specific protein biomarker detection.
• To improve signal-to-noise ratios (SNR) and capture efficiency for protein analysis in clinical samples.
• To enable rapid and accurate quantification of retinol-binding protein 4 (RBP4) for potential clinical diagnostics.

Main Methods:

• Utilized a double-antibody sandwich technique to specifically capture and amplify target antigens.
• Systematically optimized key parameters including buffer composition, voltage, antibody concentration, and pore dimensions.
• Employed solid-state nanopores for ion current monitoring and signal detection.

Main Results:

• Achieved significant improvement in SNR and effective discrimination of target signals from background noise.
• Demonstrated precise and reliable detection of retinol-binding protein 4 (RBP4) with a linear response from 55 fM to 5.5 pM.
• Successfully quantified RBP4 in clinical urine samples within 40 minutes with 100% accuracy in distinguishing chronic kidney disease (CKD) patients from healthy donors.

Conclusions:

• The developed double-antibody nanopore method significantly enhances protein detection sensitivity and specificity.
• This approach provides a robust platform for the rapid clinical diagnosis of protein biomarkers like RBP4.
• The study offers valuable insights into advancing nanopore technology for practical healthcare applications.