Nano Archive

Fabrication and physical evaluation of a polymer-encapsulated paramagnetic probe for biomedical oximetry

Meenakshisundaram, Guruguhan and Eteshola, Edward and Pandian, Ramasamy P. and Bratasz, Anna and Lee, Stephen C. and Kuppusamy, Periannan (2009) Fabrication and physical evaluation of a polymer-encapsulated paramagnetic probe for biomedical oximetry. Biomedical Microdevices, 11 (4). pp. 773-782.

Full text is not hosted in this archive but may be available via the Official URL, or by requesting a copy from the corresponding author.


Lithium octa-n-butoxynaphthalocyanine (LiNc-BuO) is a promising probe for biological electron paramagnetic resonance (EPR) oximetry and is being developed for clinical use. However, clinical applicability of LiNc-BuO may be hindered by potential limitations associated with biocompatibility, biodegradation, and migration of individual crystals in tissue. To overcome these limitations, we have encapsulated LiNc-BuO crystals in polydimethyl siloxane (PDMS), an oxygen-permeable and bioinert polymer, to fabricate conveniently implantable and retrievable oxygen-sensing chips. Encapsulation was performed by a simple cast-molding process, giving appreciable control over size, shape, thickness and spin density of chips. The in vitro oxygen response of the chip was linear, reproducible, and not significantly different from that of unencapsulated crystals. Cast-molding of the structurally-flexible PDMS enabled the fabrication of chips with tailored spin densities, and ensured non-exposure of embedded LiNc-BuO, mitigating potential biocompatibility/toxicological concerns. Our results establish PDMS-encapsulated LiNc-BuO as a promising candidate for further biological evaluation and potential clinical application.

Item Type:Article
Uncontrolled Keywords:EPR oximetry - Oxygen sensor - Particulate probe - Encapsulation - Polymer coating - Biocompatible EPR probe
Subjects:Material Science > Nanofabrication processes and tools
Biomedical Science > Nanomedicine
ID Code:5856
Deposited By:IoN
Deposited On:24 Aug 2009 11:48
Last Modified:24 Aug 2009 11:48

Repository Staff Only: item control page