Poly(p-phenylenediamine) nanofibers having conjugated structures, a novel, simple and highly selective fluorescent probe for l-cysteine

In this paper, the poly(p-phenylenediamine) (PpPD) nanofibers were synthesized via chemical oxidation polymerization of p-phenylenediamine (pPD) monomers by (NH4)2S2O8 (APS) at room temperature. The structure, morphology and properties of the polymer were characterized with IR, UV–vis, Raman spectroscopy, XRD, scanning electron microscope (SEM), and fluorescence spectroscopy. It is spectacular that the PpPD nanofibers show high-efficiency effects of enhancing the fluorescence intensity of l-Cys. Therefore, PpPD can be used as a novel, simple and highly selective fluorescent probe to detect l-cysteine. This measuring method is simple, efficient, pollution-free, low-cost and sensitive. The possible formation mechanism involved is also discussed.