Biomedical Microdevices

, Volume 7, Issue 1, pp 47–52

In Vitro and In Vivo Characterization of MEMS Microneedles

  • Melissa Ai Ling Teo
  • Christopher Shearwood
  • Kian Chye Ng
  • Jia Lu
  • Shabbir Moochhala
Article

DOI: 10.1007/s10544-005-6171-y

Cite this article as:
Teo, M.A.L., Shearwood, C., Ng, K.C. et al. Biomed Microdevices (2005) 7: 47. doi:10.1007/s10544-005-6171-y

Abstract

Transdermal drug delivery TDD systems have many advantages but are conventionally limited by the low permeability of skin. The idea of using microneedles to painlessly penetrate the topmost impermeable stratum corneum has previously been put forward. In this paper, the fabrication of solid and hollow silicon microneedles with straight side-walls and with the following dimensions: 20–100 μm in diameter and 100–150 μm in length is described. In vitro tests demonstrate that with prior solid microneedle application, transdermal drug transport is significantly increased by 10–20 times, with the degree of enhancement being related to needle diameter. In vivo tests in diabetic animals, however, were unable to demonstrate any delivery of insulin through the hollow microneedles. It is proposed that two factors, microneedle length and tip sharpness, have to be improved for systemic drug delivery to be seen in vivo.

Key Words

transdermal drug deliverymicroneedlesin vitro characterizationdiabetic rat model

Copyright information

© Springer Science + Business Media, Inc. 2005

Authors and Affiliations

  • Melissa Ai Ling Teo
    • 1
  • Christopher Shearwood
    • 2
  • Kian Chye Ng
    • 1
  • Jia Lu
    • 1
  • Shabbir Moochhala
    • 1
  1. 1.Defence Science OrganisationDefence Medical & Environmental Research InstituteSingapore
  2. 2.School of Mechanical & Production EngineeringSingapore