Development of a colorimetric nanofibrous film sensor based on polycaprolactone (PCL) incorporated with alizarin for tracking shrimp freshness

In this study, a colorimetric nanofibrous film was developed using polycaprolactone (PCL) and alizarin through electrospinning, and the film was subsequently employed for tracking shrimp freshness. Scanning electron microscopy (SEM) showed that the film was composed of beaded, continuous and smooth nanofibers. In the pH range of 4–13, the nanofibrous films displayed discernible color changes from yellow green to bluish-purple. Furthermore, when used together with shrimps, the films underwent a color change from yellow to purple, demonstrating a robust association with TVB-N and the pH value. Thus, the alizarin-based colorimetric nanofibrous films developed here could be potentially used as an indicator for tracking the freshness of shrimps.