2134/4086
Adam Davidson
Adam
Davidson
Barrak Al-Qallaf
Barrak
Al-Qallaf
Diganta Das
Diganta
Das
Transdermal drug delivery by coated microneedles : geometry effects on effective skin thickness and drug permeability
Loughborough University
2009
Effective skin permeability
Effective skin thickness
Transdermal drug delivery
Coated microneedles
Chemical Engineering not elsewhere classified
2009-01-12 15:32:07
Journal contribution
https://repository.lboro.ac.uk/articles/journal_contribution/Transdermal_drug_delivery_by_coated_microneedles_geometry_effects_on_effective_skin_thickness_and_drug_permeability/9241859
Although transdermal drug delivery has been used for about three decades, the range of
therapeutics that are administered this way is limited by the barrier function of the stratum
corneum (the top layer of skin). Microneedle arrays have been shown to increase the drug
permeability in skin by several orders of magnitude by bypassing the stratum corneum. This 15
can potentially allow the transdermal delivery of many medicaments including large
macromolecules that typically cannot diffuse through the skin. This paper addresses the use of
microneedles coated with a drug solution film. In particular, we identify how the geometries
of various microneedles affect the drug permeability in skin. Effective skin permeability is
calculated for a range of microneedle shapes and dimensions in order to identify the most 20
efficient geometry. To calculate effective permeability (Peff), the effective skin thickness (Heff)
is calculated. These are then plotted for insulin as a model drug to see how various
microneedle parameters affect the profiles of both Heff and Peff. It is found that the depth of
penetration from the microneedle array is the most important factor in determining Peff,
followed by the microneedle spacings. Other parameters such as microneedle diameter and 25
coating depth are less significant.