Fabricating Reproducible, Reversible, and High Signal Change Aptasensors with Gold-Modified Nanopipettes

ACS Applied Materials & Interfaces, Journal Year: 2025, Volume and Issue: unknown

Published: April 21, 2025

Aptamer-functionalized nanopipettes are an emerging class of biosensors for the label-free detection specific molecules. While various strategies exist immobilizing single-stranded DNA aptamers onto inner walls glass nanopipettes, impact fabrication method on sensor sensitivity, signal change, reproducibility, and reliability remains unexplored. In this study, we compared three methods found that sensors fabricated using gold nanoparticles (AuNPs) synthesized within produced most reproducible results while also allowing control over modification process. contrast, two other aptamer immobilization methods, which relied multistep polymer coatings with aminated or thiolated coupling, were hindered by water sensitivity uneven deposition, resulting in inconsistent responses. Using AuNP-coated successfully numerous varying sizes, demonstrating smaller produce greater changes. Sensors constructed diameters ranging from 22 to 30 nm exhibited large changes (>40%) when AuNP synthesis particles near tip opening without causing blockage. However, observed significantly lower (using same-sized nanopipettes), attributed either minimal Au present at conversely blocked probe. These highlight critical role maximizing enhancing identifying how why fail. This work aims facilitate broader adoption aptamer-functionalized analytical sensing applications.

Language: Английский

Understanding Sensitivity in Nanoscale Sensing Devices

ACS Measurement Science Au, Journal Year: 2025, Volume and Issue: unknown

Published: April 14, 2025

Language: Английский