Antibacterial activity of cyclodextrin-Azo dye inclusion complex encapsulated electrospun polycaprolactone nanofibers

Polycaprolactone (PCL) nanofibers incorporating azo dye/γ-cyclodextrin inclusion complex (Azo/γ-CD-IC) were successfully produced. The characteristics of the Azo/γ-CD-IC and PCL/Azo/γ-CD-IC nanofibers were investigated by X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR) and thermogravimetric analysis (TGA). Based on the SEM analysis the prepared nanofiber has a smooth surface with a size diameter below 500 nm. Meanwhile, the thermal stability of Azo was further improved after being embedded into Azo/γ-CD-IC and the PCL/Azo/γ-CD-IC nanofibers. Proton nuclear magnetic resonance (1H-NMR) was used to calculate the molar ratio of Azo/γ-CD. The antibacterial activity of the PCL/Azo/γ-CD-IC and PCL/Azo nanofibers was investigated using colony counting method and bacterial strains of Escherichia coli and Staphylococcus aureus were used. The results indicated that PCL/Azo/γ-CD-IC nanofibers have enhanced antibacterial activity against Escherichia coli and Staphylococcus aureus compared to PCL/Azo owing to inclusion complexation. Therefore, these PCL/Azo/γ-CD-IC nanofibers might have potential applications in the biomedical field.