Abstract
Transdermal delivery has made an indispensable impact to medical practice, but often been limited by low efficiency due to the barrier of the outer stratum corneum layer of skin. In Issue 9 of Theranostics, Huang et al. [1] proposed a new design of transdermal gene delivery strategy via the combination of a microneedle roller and a flexible interdigitated electroporation array. With the assistance of the microneedle roller, a deep and uniform electric field in the skin can be formed, accompanying an enhanced transport efficiency even at a low voltage. Furthermore, this combination strategy can promote the gene expression and siRNA transfection in mice skin in a safe and convenient process.