title: Multilayered pyramidal dissolving microneedle patches with flexible pedestals for improving effective drug delivery.
abstract: Dissolving microneedles have been employed as a safe and convenient transdermal delivery system for drugs and vaccines. To improve effective drug delivery, a multilayered pyramidal dissolving microneedle patch, composed of silk fibroin tips with the ability of robust mechanical strength, rapid dissolution and drug release supported on a flexible polyvinyl alcohol (PVA) pedestal is reported. To show the utility of this approach the ability of the fabricated microneedles to deliver insulin is demonstrated. The dissolving microneedles have sufficient mechanical strength to be inserted into abdomen skin of mice to a depth of approximately 150μm, and release their encapsulated insulin into the skin to cause a hypoglycemic effect. The fabrication of microneedles avoids high temperature which benefits storage stability at room temperature for 20d. This result indicates >99.4% of insulin remained in the microneedles. In comparison to traditional needle-based administration, the proposed multilayered pyramidal dissolving microneedle patches enable self-administration, miniaturization, pain-free administration, drug delivery and drug stability, all being important features in needle free drug delivery.
authors: Department of Biomedical Engineering, School of Medicine, Tsinghua University, Beijing, 100084, China.
authors: Shinying
authors: S
authors: Lau
authors: Department of Biomedical Engineering, School of Medicine, Tsinghua University, Beijing, 100084, China.
authors: Jie
authors: J
authors: Fei
authors: Department of Biomedical Engineering, School of Medicine, Tsinghua University, Beijing, 100084, China; Graduate School at Shenzhen, Tsinghua University, Shenzhen, 518055, China.
authors: Haoran
authors: H
authors: Liu
authors: Department of Biomedical Engineering, School of Medicine, Tsinghua University, Beijing, 100084, China.
authors: Weixing
authors: W
authors: Chen
authors: Department of Biomedical Engineering, School of Medicine, Tsinghua University, Beijing, 100084, China. Electronic address: liuran@tsinghua.edu.cn.
authors: Ran
authors: R
authors: Liu
mesh_terms: D000279:Administration, Cutaneous; D000818:Animals; D016503:Drug Delivery Systems / Q000379:methods; D004355:Drug Stability; D006801:Humans; D007004:Hypoglycemic Agents / Q000008:administration & dosage / Q000737:chemistry / Q000494:pharmacology*; D007328:Insulin / Q000008:administration & dosage / Q000737:chemistry / Q000494:pharmacology*; D055595:Mechanical Phenomena; D051379:Mice; D008845:Microinjections; D009339:Needles; D011142:Polyvinyl Alcohol / Q000737:chemistry*; D012867:Skin / Q000378:metabolism*; D012869:Skin Absorption; D012995:Solubility
chemical_list: D007004:Hypoglycemic Agents; D007328:Insulin; D011142:Polyvinyl Alcohol
keywords: Flexible; Insulin; Microneedles; Multilayer; Pyramidal dissolving; Transdermal delivery