Polymer Microneedle Array Integrated with CNT Nanofilter for Selective Drug Delivery Review Decision

An innovative process to integrate microneedle and CNT nanofilter is developed to realize a selective transdermal drug delivery. The microneedle is fabricated with SU-8 by double drawing lithography process. These microneedles are strong enough to penetrate skin easily and deliver drugs to the tissues under it. The CNT bundles integrated within microneedles could act as nanofilters to block all the micro-scale substance and selectively deliver drugs. Two kinds of biomolecules, glucose and Hemagglutinin, are used for tests. Glucose, whose dimension is much smaller than the inner diameter of the CNT hollow channel, could pass the CNT nanofilter just by applying pressure. The transport rate is proportional to the pressure applied. Hemagglutinin, which is a kind of cylindrical molecules whose dimension is close to the inner diameter of the CNT hollow channels, cannot pass through the CNT nanofilter just by applying pressure. In our previous study, we already confirmed that only when both electric field and pressure are applied together, hemagglutinin could be aligned by DEP force then pass through the CNT nanofilter. When glucose and hemagglutinin are mixed together, the delivery of hemagglutinin could be controlled by electric field when the glucose is always delivered by applying pressure.