Experimental and theoretical investigation of the effects of low-frequency sonophoresis on transdermal drug transport

Transdermal drug delivery offers many advantages over traditional drug administration methods such as injections and oral delivery, including increased patient compliance, and avoiding first-pass effects. However, due to the low skin permeability, transdermal drug delivery is currently limited to only a handful of drugs that are hydrophobic and of low molecular weight. The pharmaceutical relevance of many molecules that are excluded from this category, such as proteins, peptides, and DNA, has stimulated the investigation of various skin permeation enhancement methods, among which ultrasound represents a promising skin permeation enhancer. Previous work by our group has shown that ultrasound at a frequency of 20 kHz significantly enhances transdermal transport of drugs, a phenomenon referred to as Low-Frequency Sonophoresis (LFS). The objective of this thesis was to develop a fundamental understanding of the mechanisms of low-frequency sonophoresis (LFS) with an emphasis on the transdermal transport of hydrophilic permeants. An important goal was to utilize this mechanistic understanding to develop guidelines for the rational design of clinical LFS systems. With this in mind, a transport theory was developed to characterize the skin porous pathway of hydrophilic permeants, and to account for the effects of convection during LFS. Through a combined theoretical and experimental investigation of transdermal transport of hydrophilic permeants in both the presence and in the absence of ultrasound, I demonstrated that skin transport of hydrophilic permeants can be described adequately with a skin porous-pathway model.

Department dc:contributor.department

Massachusetts Institute of Technology. Dept. of Chemical Engineering.

Grantor dc:publisher

Massachusetts Institute of Technology

Year dc:date.issued

2002

Author dc:creator

• Tang, Hua, 1972-

Advisor dc:contributor.advisor

• Daniel Blankschtein.

• Chemical Engineering.

Statement dc:rights

• M.I.T. theses are protected by copyright. They may be viewed from this source for any purpose, but reproduction or distribution in any format is prohibited without written permission. See provided URL for inquiries about permission.

Licence dc:rights.uri

• http://dspace.mit.edu/handle/1721.1/7582

Language dc:language.iso

eng

Handle dc:identifier.uri

http://hdl.handle.net/1721.1/8270

OAI identifier oai:identifier

oai:dspace.mit.edu:1721.1/8270