Publication: Polymers, Vol 16, Issue 16
Ganna Zubova, Hanna Melnyk, Iryna Zaets, Tetyana Sergeyeva, Olesia Havryliuk, Sergiy Rogalsky, Lyudmila Khirunenko, Leonid Zaika, Tetina Ruban, Svitlana Antonenko, and Natalia Kozyrovska.
Abstract
Polymer-based dressings deriving from natural biomaterials have advantages such as nontoxicity, biocompatibility, and mechanical stability, which are essential for efficient wound healing and microbial infection diagnostics. Here, we designed a prototype of an intelligent hydrogel dressing on the base of bacterial cellulose (BC) for monitoring wound microbial infection due to the uploaded natural pH dye-sensor, anthocyanins (ANC) of elderberry fruit (Sambucus nigra L.). The highest sensor responses to bacterial metabolites for ANC immobilized to BC were observed at pH 5.0 and 6.0. The detection limit of the sensor signals was 3.45 A.U., as it was evaluated with a smartphone-installed application. The FTIR spectral analysis of the hybrid BC/ANC hydrogel films has proved the presence of anthocyanins within the BC matrix. Hybrid films differed from the control ones by thicker microfibrils and larger pores, as detected with scanning electron microscopy. Halochromic BC/ANC films exhibited antimicrobial activities mainly against gram-positive bacteria and yeast. They showed no cytotoxicity for the in vitro human cell lines and mouse fibroblasts within a selected range of anthocyanin concentrations released from the BC/ANC film/dressing prototype. Compared to the control, the in vitro healing test showed overgrowth of primary mouse fibroblasts after applying 0.024–2.4 µg/mL ANC.
Conclusion:
A dual-use smart hydrogel dressing prototype designed for in situ monitoring bacterial contamination in wounds possesses a stable presence of anthocyanins of Sambucus nigra L. in the BC hydrogel composition, probably due to the interaction of its functional groups with OH-groups of cellulose. The presence of anthocyanins in the BC polymer slightly altered the morphology and network of its fibrils. Anthocyanins sense a change in the pH of the microenvironment, and the color changes of the ANC sensor elements can be successfully recorded visually or with the help of commercially available digital image analysis software installed in a smartphone. The elderberry extract is not toxic for mouse fibroblasts at concentrations released from BC/AE dressing, and small AE doses stimulate their migration. The activation of mouse fibroblasts at therapeutic concentrations may predict their healing capability. Combining natural dye-pH-sensor with healing potential, the BC/AE hybrid polymer could provide an attractive initial material for simultaneous wound healing and online monitoring of bacterial metabolites.
Link to full article: https://www.mdpi.com/2073-4360/16/16/2327
