Living Dual Heat- and pH-Responsive Textiles

Abstract

Smart textiles that integrate multiple environmental sensing capabilities are an emerging frontier in wearable technology. In this study, we developed dual pH- and temperature-responsive textiles by combining engineered bacterial systems with bacterially derived proteins. For temperature sensing, we characterized the properties of a heat sensitive promoter, P_hs, in Escherichia coli (E. coli) using enhanced green fluorescent protein as a reporter. Our findings demonstrate that the P_hs promoter drives elevated gene expression at temperatures between 37 and 43 °C, maintaining sustained activity for several hours. Moreover, we found that short heat shocks can significantly boost expression levels of the P_hs promoter. We successfully integrated E. coli expressing P_hs-EGFP cells onto textiles and confirmed their ability to retain heat-responsive behavior after integration. To achieve pH responsiveness, we utilized curli fibers, genetically engineered to incorporate a pH-sensitive fluorescent protein, pHuji. pH-sensing curli fibers are bacterial proteins that have a proven track record of creating stable bioresponsive textile coatings. By embedding P_hs-EGFP-expressing bacteria within curli fiber coatings, we created a dual-responsive textile capable of differentiating between acidic and alkaline environments while simultaneously responding to thermal stimuli. These multifunctional textiles exhibited dual environmental response and sensing capabilities. This work establishes a proof-of-concept for creating smart living textiles with modular functionalities, paving the way toward advanced bioresponsive materials.