Magnetically induced protein gradients on electrospun nanofibers

Peripheral nerve regeneration can be significantly enhanced by the distribution of the extracellular matrix (ECM) proteins at an increasing concentration along the length of a scaffold. In this study, we have created a gradient of an extracellular matrix protein, laminin, on nanofibrous scaffolds using an external magnetic field. The laminin was crosslinked to ferritin, a biocompatible protein with functional amino and carboxylic acid groups on the surface and a magnetically inducible iron core. The presence of laminin gradients on the scaffolds was demonstrated through immunofluorescent staining with antibodies against laminin. When culturing Schwann cells on the nanofibrous scaffolds, the number of cells increased along the gradients with increasing laminin concentrations. The method developed in this study allows for precise control over the gradient formation in terms of distances and concentrations and thus provides a platform for high throughput screening of cell materials interactions. The nanofibrous scaffolds with laminin gradients can be potentially used in neural tissue engineering.