Fabrication of a novel fluorescent polyacrylonitrile electrospun nanofiber for DNA-based optical biosensing of microRNA-21

In this study, an optical platform based on fluorescent nanofiber was developed for detection of microRNA-21 as a biomarker of cancerous cells. The fluorescent polyacrylonitrile nanofiber was fabricated using electrospinning method. The surfaces of nanofiber were treated by NaOH to convert nitrile groups to carboxyl moieties. Activation of these carboxyl groups by EDC-sulfo NHS coupling agents was done and then the covalent bonding between COOH groups of nanofiber and -NH2 groups of amino-probe was formed. The results of SEM, XRD, FTIR, and fluorescence microscopy confirmed that the process of fluorescent nanofiber synthesis was successfully performed. Hybridization of probe and microRNA-21 showed that the capture efficiency of this fluorescent nanofiber was 1 pmol mu l(-1) and these nanofibers have the potential to be used as optical sensors for detection of microRNA-21.