Aptamer-based colorimetric assay on poly(allylamine)-blended polycaprolactone electrospun nanofibers for CD36...

A new bioanalytical system was designed to provide colorimetric determination on nanofibers for the determination of CD36, a biomarker of atherosclerosis. First, electrospun nanofibers (ENFs) with a bead-free morphology and hydrophilic surface were produced using electrospinning with polycaprolactone (PCL) and poly(allylamine) hydrochloride (PAH) polymers. Bioconjugates were prepared using CD36-specific aptamers and gold nanoparticles (AuNPs) for the determination of CD36. Aptamer-AuNPs bioconjugates were incubated with various concentrations of CD36. Then, mixtures of CD36 and Aptamer-AuNPs bioconjugates were applied on NaCl-pretreated PCL-PAH ENFs. Visible color changes occurred on the PCL-PAH ENFs in proportion to the increasing CD36 concentrations. Each color intensity was recorded using a smartphone camera. The linear range of the colorimetric bioassay designed on the PCL-PAH ENFs was found to be 25-400 ng•mL^- 1 CD36 with a limit of detection (LOD) of 23.1 ng•mL^- 1. CD36 detection was successfully performed in spiked commercial serum samples. To the best of our knowledge, this study presents the first aptamer-based colorimetric method for optical detection of CD36.