Conductive Textile Structures for Haemorrhage Detection: Electrical Resistance-Based Sensing and Performance Evaluation

The electrical response of conductive textile structures to liquid exposure was investigated as a basis for electrical resistance-based haemorrhage detection. The sensing principle relies on changes in the electrical resistance of the conductive network following liquid exposure, with the resulting resistance variation used as the sensing parameter. Nine conductive textile variants were developed and evaluated, comprising three knitted structures (K1–K3) and six woven structures produced in raw and finished states (W1–W3). The structures incorporated silver-coated polyamide and stainless-steel conductive yarns and were exposed to water, acidic perspiration (pH 5.5), alkaline perspiration (pH 8.0), and saline solution. Saline solution was used as a controlled conductive aqueous medium for comparison and does not reproduce the physical, chemical, rheological, cellular, or biochemical properties of whole blood. Electrical resistance measurements, together with physical and mechanical characterization, scanning electron microscopy (SEM), and Fourier-transform infrared spectroscopy (FTIR), were performed to assess structural stability and electrical response. Saline solution produced the largest resistance variations among the tested liquids, whereas water and perspiration resulted in lower responses. Localized mechanical deformation further induced pronounced resistance changes in several woven structures. Among the evaluated variants, W2 exhibited the most favorable combination of structural stability and electrical responsiveness. These results support further investigation of W2 (conductive yarn: Filix DA5393 yarn) as an electrical resistance-based sensing structure for potential haemorrhage-related liquid detection applications.