Poster
Presentation 23:
Evaluation and Characterization of PHEMA Sponges as Implantable
Drug Delivery Systems
Thomas D. Dziubla1, Marc
C. Torjman2, Jeffrey I. Joseph2 and Anthony M. Lowman1
School of Biomedical Science Engineering and Health
Systems
1Drexel University
3141 Chestnut Street
Philadephia, PA 19104
td25@Drexel.edu
(215) 895-5831
2Thomas Jefferson
University
Implantable drug delivery devices are being pursued as
a means of long-term quick-delivery vehicle of bioactive substances to
the body. The draw back to most implantable devices is the chronic-inflammatory
response that results in the avascular fibrous encapsulation of the implant,
which prevents the device from effectively administering the drug over
a long period of time. One method of overcoming this problem is the
addition of an intermediate that prevents this capsule formation.
Biocompatible materials with interconnected pores greater
than 10µm have been shown to support the ingrowth and maintenance
of vascularized tissue. Implants coated in such a porous material would
not be encapsulated but actually generate a direct route for fast systemic
delivery as well as anchoring the implant to the surrounding soft tissue.
In this work, we synthesize and evaluate the use of poly
(2-hydroxy ethyl methacrylate) (PHEMA) sponges as an intermediate for an
implantable drug delivery system. Here we use a catheter tip as the
model system. Scanning electron microscopy (SEM) and mercury porosimetry
are used to characterize the pore microstructure of the sponges.
Also, in vitro and in vivo insulin infusion studies are performed
to evaluate the effect of the hydrogel sponges on release characteristics.
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