Substrate-Free Dissolvable Microneedles with Barbed Structure Prepared by Modified Dual-Moulding Processes

As an emerging approach in the field of drug delivery, dissolvable microneedles have been extensively developed and applied. Most of the tips are with the conical or pyramid-shap, which allows low penetration force, but the tips are easy to slip out of the skin. Moreover, the medicine in the substrate cannot be used, resulting in waste of medicine. Based on the above problems, this paper reports a new type of substrate-free dissolvable microneedles with the barbed structure, which are prepared by modified dual-moulding processes and have the potential for mass production. Compared with the traditional conical microneedle, the barbed microneedle has stronger adhesion to the skin, and takes shorter pressing time to produce more drug dissolution amount and deeper penetration depth to ensure effective transdermal delivery.