Format

Send to

Choose Destination
See comment in PubMed Commons below
J Control Release. 2006 Apr 10;111(3):252-62. Epub 2006 Feb 14.

Fabrication and characterization of microfluidic probes for convection enhanced drug delivery.

Author information

1
School of Chemical and Biomolecular Engineering, Cornell University, Ithaca, NY 14853, USA.

Abstract

Convection enhanced drug delivery (CED) is a promising therapeutic method for treating diseases of the brain by enhancing the penetration of drugs. Most controlled release delivery methods rely on diffusion from a source to transport drugs throughout tissue. CED relies on direct infusion of drugs into tissue at a sufficiently high rate so that convective transport of drug is at least as important as diffusive transport. This work describes the fabrication and characterization of microfluidic probes for CED protocols and the role diffusion plays in determining penetration. Microfluidic channels were formed on silicon substrates by employing a sacrificial photoresist layer encased in a parylene structural layer. Flow in the microchannels was characterized by applying constant upstream pressures from 35 to 310 kPa, which resulted in flow rates of 0.5-4.5 microL/min. The devices were used to infuse Evans Blue and albumin in hydrogel brain phantoms. The results of these infusions were compared to a simple convection-diffusion model for infusions into porous media. In vivo infusions of albumin were performed in the gray matter of rats at upstream pressures of 35, 70, and 140 kPa. The microfabricated probes show reduced evidence of backflow along the device-tissue interface when compared with conventional needles used for CED.

PMID:
16476500
DOI:
10.1016/j.jconrel.2005.11.018
[Indexed for MEDLINE]
PubMed Commons home

PubMed Commons

0 comments
How to join PubMed Commons

    Supplemental Content

    Full text links

    Icon for Elsevier Science
    Loading ...
    Support Center