Abstract Scope |
Herein, we present a pH-responsive hydrogel fabricated by Direct-ink-Writing (DIW) 3D printing. To realize this, we developed two inks, one contains poly (acrylamide-co-acrylic acid) hydrogel and can be utilized as the shape morphing template; the other one is composed of Ca-alginate with embedded cellulose-producing bacteria. The presence of the bacteria in the hydrogel allows in situ generation of bacterial cellulose (BC), which enhances the hydrogel's mechanical stability. We used these inks to construct a bilayer structure, which could undergo a significant shape morphing at acidic/alkaline conditions. The shape-changing effect arises from the swelling/deswelling mismatch, which is caused by the different extent of response when subject to different pH values. We evaluated the 3D printability of the two inks, in situ BC generation ability, pH-responsive performance, and internal structure of the hydrogel. Such 3D-printed engineered living material with pH-responsive capability represents an innovation in creating new types of smart soft materials. |