The present invention provides a wound dressing containing macromolecular compounds, wherein said macromolecular compounds comprise multiple blocks having a cloud point and hydrophilic blocks, have a sol-gel transition temperature in aqueous solutions, and indicate a liquid state reversibly at temperatures lower than said sol-gel transition temperature. Said system also comrises a pull-off protective coating, whereby the matrix layer contains one or more active ingredients andor one or more biologically active substances and highly dispersed silicon dioxide. The methods can include recognizing colors andor reflectivity of the coin using, for example, pixel thresholding algorithms.