eprintid: 10849
rev_number: 8
userid: 6
dir: disk0/00/01/08/49
datestamp: 2012-10-09 20:20:10
lastmod: 2016-11-15 13:55:46
status_changed: 2012-10-09 20:11:52
type: thesis_degree
metadata_visibility: show
contact_email: amf47@pitt.edu
item_issues_count: 0
eprint_status: archive
creators_name: Faraji, Amir Hussein
creators_email: amf47@pitt.edu
creators_id: AMF47
title: Convection-Enhanced Delivery of Macromolecules to the Brain Using Electrokinetic Transport
ispublished: unpub
divisions: sch_as_chemistry
full_text_status: public
keywords: drug delivery; glioma; brain tumors; electroosmosis; electrophoresis; convection-enhanced delivery
abstract: Electrokinetic transport in brain tissue represents the movement of molecules due to an applied electric field and the interplay between the electrophoretic and electroosmotic velocities that are developed. This dissertation provides a framework for understanding electrokinetic transport and how it may be utilized for short-distance ejections, relevant to capillary iontophoresis, and long-distance infusions, for the clinical management of malignant brain tumors as a novel convection-enhanced drug delivery system.In particular, electrokinetic transport was first analyzed in a series of poly(acrylamide-co-acrylic acid) hydrogels that demonstrated varying electroosmotic velocities. Moreover, a hydrogel was synthesized to mimic the electrokinetic properties of organotypic hippocampal slice cultures (OHSC), as a surrogate for brain tissue. Short- and long-distance capillary infusions of molecules into the hydrogels and OHSC provided a framework to understand the relevant phenomena, such as the effect of varying the capillary tip size, applied electrical current, ζ-potential of the capillary or the outside matrix, infusion time, tortuosity, and properties of the solute (including molecular weight and electrophoretic mobility). Control of the directional transport of molecules was also demonstrated over a distance of several hundred micrometers to millimeters. Finally, electrokinetic infusions were conducted in vivo in the adult rat brain, with results compared to those of pressure-driven infusions.The experiments and results described in this dissertation provide a foundation for further development, by presenting a methodical means to increase the ejection profile and attain clinically relevant penetration distances while minimizing adverse effects to the brain tissue, including from the electric field itself. The rate of electrokinetic transport is greater than the rate of diffusion, and therefore it represents a novel form of convection-enhanced drug delivery system.
date: 2011-09-30
date_type: completed
institution: University of Pittsburgh
refereed: TRUE
etd_defense_date: 2011-07-06
etd_approval_date: 2011-09-30
etd_submission_date: 2011-07-14
etd_release_date: 2011-09-30
etd_access_restriction: immediate
etd_patent_pending: TRUE
assigned_doi: doi:10.5195/pitt.etd.2011.10849
thesis_type: dissertation
degree: PhD
committee: Adrian C. Michael (amichael@pitt.edu) - Committee Member
committee: Ian F. Pollack, M.D. (pollaci@upmc.edu) - Committee Member
committee: Stephen G. Weber (sweber@pitt.edu) - Committee Chair
committee: Billy W. Day (bday@pitt.edu) - Committee Member
etdurn: etd-07142011-113306
other_id: etd-07142011-113306
citation:   Faraji, Amir Hussein  (2011) Convection-Enhanced Delivery of Macromolecules to the Brain Using Electrokinetic Transport.  Doctoral Dissertation, University of Pittsburgh.    (Unpublished)  
document_url: http://d-scholarship-dev.library.pitt.edu/10849/1/FarajiAH_ETD_2011.pdf