Combined covalent and noncovalent carboxylation of carbon nanotubes for sensitivity enhancement of clinical immunosensors

Abstract

We report here for the first time with quantitative details that the combination of pi–pi stacking of pyrenecarboxylic acid with chemically carboxylated multiwalled carbon nanotubes (MWNT-COOH) offers superior sensitivity compared to MWNT-COOH alone for serum insulin measurements and that this combination is broadly applicable for biosensors, drug delivery, and catalytic systems.