Pathology

Neuroscience

Nanotechnology

Iontophoresis

Stratum corneum

Operations research

Porosity

Biology

Engineering

Biomedical engineering

Composite material

Materials science

Transdermal

Transdermal patch

Computer science

Penetration (warfare)

Computer vision

Chemical engineering

Resistive touchscreen

Medicine

Pharmacology

Nature Communications

A microneedle array is an attractive option for a minimally invasive means to break through the skin barrier for efficient transdermal drug delivery. Here, we report the applications of solid polymer-based ion-conductive porous microneedles (PMN) containing interconnected micropores for improving iontophoresis, which is a technique of enhancing transdermal molecular transport by a direct current through the skin. The PMN modified with a charged hydrogel brings three innovative advantages in iontophoresis at once: (1) lowering the transdermal resistance by low-invasive puncture of the highly resistive stratum corneum, (2) transporting of larger molecules through the interconnected micropores, and (3) generating electroosmotic flow (EOF). In particular, the PMN-generated EOF greatly enhances the transdermal molecular penetration or extraction, similarly to the flow induced by external pressure. The enhanced efficiencies of the EOF-assisted delivery of a model drug (dextran) and of the extraction of glucose are demonstrated using a pig skin sample. Furthermore, the powering of the PMN-based transdermal EOF system by a built-in enzymatic biobattery (fructose / O 2 battery) is also demonstrated as a possible totally organic iontophoresis patch.

Transdermal electroosmotic flow generated by a porous microneedle array patch