Electrospun polycaprolactone:gelatin (PCL:GT) fibre scaffolds are widely employed in the field of tissue implants. Here, the orientation of fibres plays an important role in regard to implantation due to the impact on the mechanical properties. Likewise, the orientation of collagen fibres in skin tissue is relevant for dermatology. State-of-the-art fibre orientation measurement methods like electron microscopy are time consuming and destructive. In this work, we demonstrate polarimetry as a non-invasive approach and evaluate its potential by measuring the Mueller matrix (MM) of gelatin and collagen containing samples as simple skin tissue phantoms. We demonstrate that it is possible to determine the orientation of PCL:GT fibre scaffolds within one MM measurement. Furthermore, we determine the structural orientation in collagen film samples. Currently, the diagnosis of skin diseases is often performed by image analysis or histopathology respectively, which are either subjective or invasive. The method presented, here, provides an interesting alternative approach for such investigations. Our findings indicate that the orientation of collagen fibres within skin lesions might be detectable by MM measurements in the future, which is of interest for skin diagnostics, and will be further investigated during the next step.
Keywords: Mueller matrix; Raman spectroscopy; collagen; electrospinning; fibre alignment; gelatin; tissue engineering.