Smart Colour Textiles is a technology for highly stable coupling of indicator dyes and sensor pigments to fibres, yarns and fabrics. Thus, textiles and dressing materials can be equipped with specific sensor properties, which may find use in medical diagnostics. These materials are washable and stable against elevated temperatures, do not affect the wearing comfort and can be used reversibly.
As part of the project, specific indicator dyes are developed in order to e.g.
- Detect metabolites of a bacterial infection in wounds (biogenic amines, hydrogen sulfide). A distinct colour change of the dressing material can indicate when a therapy is required
- Indicate if a washing solution for the skin of babies is too alkaline and will cause irritations. This is accomplished by a sensor textile (e.g. a washcloth) that shows a colour change from green to red upon increasing pH
To exclude contamination by dyes, a covalent binding of the indicator dyes to textiles and non-wovens is crucial. For the quantitative evaluation of the sensor fabrics, they may be combined with opto-electronic evaluation (fiber optics, smart phones).
In addition to the synthesis of new functional dyes, the production process of textile sensors is researched as well:
- Yarns and textiles are dyed directly, as well as sensor pigments, which are mixed into the spinning solution prior to the spinning of the fibres
- In the case of textile materials that cannot be coloured covalently (e.g. polyester) sensor pigments are embedded into binder polymers and processed via screen or template printing
- Using the electro-spinning technology nano-fibres are prepared that exhibit extremely fast response and high sensitivity
- Preparation of new indicator dyes for pH, Na+, Ca2+, Mg2+, amines and thiols
- Binding of indicator dyes to textile materials and non-wovens
- Characterisation of sensor materials with respect to stability, colour change, sensitivity, reversibility, washability, sterilisability and toxicity
- Fabrication of sensor textiles for the detection of pH and electrolytes (Na+, Ca2+, Mg2+) in sweat
- Preparation of sensor wound dressings for the detection of pH, or metabolites of microbial contamination (amines, thiols) for monitoring of wound healing
- Preparation if indicator swabs and indicator tests for the control of pH in (chronic) wounds
- Programming of smartphones/tablets for the quantitative evaluation of colour changes
- Development of a fibre-optic system for the detection of colour changes within textiles and non-wovens (in the case of no direct optical visibility)
- Adaption of existing optical sensor devices (CCD technology, colour measurement devices, colour sensing chips) to the colour changes of textile materials