Plant extracted natural fluorescent protein C-phycocyanin doped in PVA nanofibers for advanced apparel application

Natural dyes are gaining a great deal of attention due to their eco-friendly and sustainable properties for advanced apparel applications. However, the reproducibility and accessibility of various colors using natural dyes remain challenging. In this study, plant-extracted fluorescent protein C-phycocyanin (CP) is used as a natural dye source and doped in polyvinyl alcohol (PVA) nanofibers via electrospinning for advanced apparel applications. The prepared nanofibers show a smooth and bead-free surface morphology. The FTIR results confirmed the formation of PVA nanofibers followed by a major peak at 3304 cm(-1) due to the stretching of hydroxyl groups. Subsequently, CP-doping in PVA nanofibers is observed by the N-H deformation peaks at 1541 cm(-1); C-N stretching vibrations at 1250 cm(-1) and 1092 cm(-1); and the C=O stretching vibrations of the carboxyl group at 1722 cm(-1), respectively. Thus, CP-doped PVA nanofibers exhibit a good color strength (K/S) of 0.2 having a blue color tune and good color fastness properties. The mechanical strength of PVA nanofibers increased from 6 MPa to 18 MPa, due to crystalline characteristics endowed by the dope dyeing technique. Further, CP-doped PVA nanofibers exhibit homogeneous bright red fluorescence in individual nanofibers. Therefore, the proposed CP-doped PVA nanofibers can be used for flexible advanced apparel and biosensor applications.