| abstract |
Disclosed herein is an article that includes a first plurality of spaced features. The spaced features are arranged in a plurality of groupings; the groupings of features include repeat units; the spaced features within a grouping are spaced apart at an average distance of about 1 nanometer to about 500 micrometers; each feature having a surface that is substantially parallel to a surface on a neighboring feature; each feature being separated from its neighboring feature; the groupings of features being arranged with respect to one another so as to define a tortuous pathway. The plurality of spaced features provide the article with an engineered roughness index of about 5 to about 20. |