A paper-supported aptasensor for total IgE based on luminescence resonance energy transfer from upconversion nanoparticles to carbon nanoparticles

Abstract

A paper-supported aptasensor was constructed for total IgE using a luminescence resonance energy transfer (LRET) protocol with upconversion nanoparticles (UCNPs) as energy donors and carbon nanoparticles (CNPs) as energy acceptors. This is the first time that zero-dimensional carbon nanoparticles were used as energy acceptors for paper-based LRET assays. The π-π stacking interaction between the aptamer and CNPs brought the energy donor (UCNPs) and energy acceptor (CNPs) in close proximity, induced the LRET process on the surface of paper and thus led to the luminescence quenching of UCNPs. The introduction of IgE inhibited the energy transfer and hence recovered the luminescence of UCNPs in a concentration-dependent manner, as a result of the recognition between IgE and aptamer. This aptasensor can be used to detect IgE concentration in the range of 0.5–80ng/mL in both buffer solution and human serum samples. The IgE concentrations measured by our method were well correlated to those obtained from chemiluminescence-based clinical assay. Owing to its simplicity and accuracy, the proposed sensor thus showed the potential of clinical applications.