Plant dye-based sensors for monitoring of wound status

The new sensor with sensitive pH-response is highly desirable material for monitoring wound infection. However, most of the indicator dyes used are synthesized by chemical methods, which pose a potential threat to human health. Therefore, we developed a pH sensor based on sappanwood plant dye. The pigment is extracted from natural plants and dyed on the fabric to obtain the pH-response discoloration of fabric. The change color rules are characterized by UV-visible-light spectrophotometer and the concept of CIELab space. The discoloration time of two kinds of dyed fabrics is also obtained. The experimental results show that the color of the dyed fabric are three different colors visible to the naked eye at pH 6, 7 and 8. The response time of color change is 18 s and 7 s, respectively. The results showed that the plant dyestuff of sappanwood had the same response to change color as the chemical dyestuff and could be used as an indicator for wound monitoring.