Functional pH-sensitive cellulose fabric dyed with bacterial extract from Streptomyces sp.

Abstract

In this work, cellulose (viscose) was functionalized with chitosan and dyed with an extract of Streptomyces sp. NP4 bacterial culture. Cellulose was first converted to dialdehyde cellulose; afterward chitosan was deposited, making fabric susceptible to dyeing. The dyed fabric exhibited pH responsiveness in a broad range of pH, 4-7-10, where colour shade of the fabric, exposed to buffer solutions, was pink, red, and blue, respectively. Response to the pH change was measured in seconds, whereby faster colour shift is from blue to red/pink. The dyed fabrics can withstand 10 cycles of colour change. Due to the broad range of pH activity, the presented cellulose product has the potential to be used as a textile pH sensor, and, more importantly, it is completely made from natural and sustainable resources.