Microfluidic Paper-Based Analytical Device for Sensitive Detection of Peptides Based on Specific Recognition of Aptamer and Amplification Strategy of Hybridization Chain Reaction

In this paper, a microfluidic paper-based analytical device is presented for sensitively detecting peptides based on the specific recognition of aptamer and the amplification strategy of hybridization chain reaction (HCR). The aptamer/initiation strand (AP/IS) was designed for the specific target recognition, and the presence of the target peptide could release the initiating sequence from the AP/IS. The released IS could trigger the HCR between two hairpin probes, which could complete the detection for the targets indirectly when the electro-chemiluminescence (ECL) probe (Ru(phen)(3)(2+)) is introduced into the double-strand DNA grooves, which could produce a significantly amplified ECL signal output. Mucin-1 was employed as a model peptide, and the detection limit of the proposed assay is calculated as 8.33 pMwith a range from 25 pM to 50 nM. The novel sensing platform can be widened for the detection of other kinds of peptides as well as potentials used for sensitively detecting other biomolecules, and even cells.