Fabrication of pH-responsive self-assembled biofilament and its application in non-invasive monitoring of wound healing

Abstract

Conventional wound healing assessment techniques are often invasive and may interfere with the natural healing process, creating a critical need for non-invasive detection system. To address this challenge, the present work reports the development of a fluorescent bio-filament composed of κ-Carrageenan and Chitosan polysaccharides, fabricated via polyelectrolyte complexation, with Pyranine serving as both crosslinker and fluorescent marker. By leveraging pH sensitivity, the developed filament effectively serves as a non-invasive wound pH detector. A comprehensive analysis of the resultant filaments was performed. The mechanical properties, such as tensile strength and elongation at break were thoroughly evaluated. Chemical and structural properties were analyzed using Fourier-transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), and UV-visible spectroscopy. Scanning electron microscopy (SEM) confirmed the morphologically uniform filament structure, while thermal analysis demonstrated enhanced thermal stability of the composite filament relative to its precursor materials. Importantly, fabrication process is additive-free and toxic solvent-free addressing sustainability and biocompatibility requirements. To our knowledge, this is the first report on the synthesis of a composite filament integrating κ-Carrageenan, Pyranine, and Chitosan, along with an in-depth investigation of its physicochemical, mechanical, and thermal properties. Furthermore, a prototype wound covering patch is developed and proof-of-concept is successfully validated using rodent model for both non-diabetic and diabetic wound groups. The results underscore the potential of this biofilament as a sustainable and non-invasive platform for the real-time wound healing assessment.