title: Microneedles with Controlled Bubble Sizes and Drug Distributions for Efficient Transdermal Drug Delivery.
abstract: Drug loaded dissolving microneedles (DMNs) fabricated with water soluble polymers have received increasing attentions as a safe and efficient transdermal drug delivery system. Usually, to reach a high drug delivery efficiency, an ideal drug distribution is gathering more drugs in the tip or the top part of DMNs. In this work, we introduce an easy and new method to introduce a bubble with controlled size into the body of DMNs. The introduction of bubbles can prevent the drug diffusion into the whole body of the MNs. The heights of the bubbles are well controlled from 75 μm to 400 μm just by changing the mass concentrations of polymer casting solution from 30 wt% to 10 wt%. The drug-loaded bubble MNs show reliable mechanical properties and successful insertion into the skins. For the MNs prepared from 15 wt% PVA solution, bubble MNs achieve over 80% of drug delivery efficiency in 20 seconds, which is only 10% for the traditional solid MNs. Additionally, the bubble microstructures in the MNs are also demonstrated to be consistent and identical regardless the extension of MN arrays. These scalable bubble MNs may be a promising carrier for the transdermal delivery of various pharmaceuticals.
authors.affiliation: Beijing Laboratory of Biomedical Materials, College of Materials Science and Engineering, Beijing University of Chemical Technology, Beijing, 100029, P.R. China.
authors.forename: Qi Lei
authors.initials: QL
authors.lastname: Wang
authors.affiliation: Beijing Laboratory of Biomedical Materials, College of Materials Science and Engineering, Beijing University of Chemical Technology, Beijing, 100029, P.R. China.
authors.forename: Dan Dan
authors.initials: DD
authors.lastname: Zhu
authors.affiliation: Beijing Laboratory of Biomedical Materials, College of Materials Science and Engineering, Beijing University of Chemical Technology, Beijing, 100029, P.R. China.
authors.forename: Xu Bo
authors.initials: XB
authors.lastname: Liu
authors.affiliation: Beijing Laboratory of Biomedical Materials, College of Materials Science and Engineering, Beijing University of Chemical Technology, Beijing, 100029, P.R. China.
authors.forename: Bo Zhi
authors.initials: BZ
authors.lastname: Chen
authors.affiliation: Beijing Laboratory of Biomedical Materials, College of Materials Science and Engineering, Beijing University of Chemical Technology, Beijing, 100029, P.R. China.
authors.forename: Xin Dong
authors.initials: XD
authors.lastname: Guo
mesh_terms: D000279:Administration, Cutaneous; D016503:Drug Delivery Systems; D008845:Microinjections; D009339:Needles