Arrowhead Subsidiary, Unidym, Signs a Collaboration Agreement with IMRE to Develop Organic Light Emitting Diodes Incorporating Unidym's Transparent Electrodes.

PASADENA, Calif. -- Arrowhead Research Corporation (NASDAQ:ARWR) announced today that its majority-owned subsidiary, Unidym, has entered into a collaborative agreement with the Institute of Materials Research and Engineering ("IMRE") in Singapore to develop organic light emitting diodes ("OLEDs") incorporating transparent electrodes made of carbon nanotubes. Under the terms of the agreement, Unidym will provide IMRE researchers with access to its proprietary, carbon nanotube-based, transparent electrodes which IMRE will incorporate into its OLED devices.

An OLED is a thin-film, light-emitting device generally comprised of organic layers between two electrodes on a glass or flexible substrate. OLEDs are primarily used for display and lighting applications. They offer bright, colorful images with a wide viewing angle and low power consumption. According to iSuppli Corp., the market for OLEDs was $408 million in 2004 and is expected to reach $2.9 billion by 2011.

Carbon nanotube-based transparent electrodes have the potential to improve the performance of OLEDs while also reducing their production costs.

"We believe IMRE is a world leader in OLED technology and are pleased that Unidym has entered this collaboration with such a distinguished institution," said R. Bruce Stewart, Chairman of Arrowhead Research. "We will continue to look for strategic partners to integrate Unidym's transparent electrodes into optoelectronic systems."

Arrowhead has an 88% ownership stake in Unidym.

About Arrowhead Research Corporation

Arrowhead Research Corporation (www.arrowheadresearch.com) (NASDAQ:ARWR) is a publicly-traded nanotechnology company commercializing new technologies in the areas of life sciences, electronics, and energy. Arrowhead is building value for shareholders through the progress of majority owned subsidiaries founded on nanotechnologies originally developed at universities. The company works closely with universities to source early stage deals and to generate rights to intellectual property covering promising new nanotechnologies. Currently, Arrowhead has four subsidiaries commercializing nanotech products and applications, including anti-cancer drugs, RNAi therapeutics, carbon-based electronics and compound semiconductor materials.

About Unidym

Unidym, Inc. is developing low-cost, carbon-based materials, processes, and devices for the electronics industry. The Company's initial product is a thin, transparent film of carbon nanotubes that replaces the expensive, failure-prone materials currently employed by manufacturers of devices such as touch screens, flat panel displays, and solid state lighting. Unidym is also developing novel carbon nanotube-based transistors and conductive inks for the printable electronics industry to replace today's complex and capital intensive semiconductor manufacturing processes with inexpensive, solution-based printing processes. Unidym differentiates itself through its emphasis on low-cost materials and processes, in-house carbon nanotube production, aggressive partnership strategy, and significant intellectual property portfolio that includes foundational IP in both of its initial applications.

About IMRE

The Institute of Materials Research and Engineering (IMRE) (www.imre.a-star.edu.sg) is a research institution of Singapore's Agency for Science, Technology and Research (A*STAR). Established in 1996, our mission is to create materials knowledge, develop human capital and to transform technology through innovative research. We undertake research in selected fields of materials science and engineering, including optoelectronics, nanomaterials, chemicals and polymers. Our innovations and discoveries are constantly being explored to further the applications of advanced materials and processes. IMRE and other research institutes under A*STAR's Science and Engineering Research Council will be co-located in Singapore's new Fusionopolis (www.a-star.edu.sg/astar/fusionopolis/index.do), scheduled for completion in 2008. Fusionopolis is the icon for physical sciences and engineering research in Singapore.

Encompassing multidisciplinary research and public-private co-location, Fusionopolis will be the focal point where world class talent and organisations congregate. The amalgamation of cutting-edge facilities and human capital will catalyse scientific innovations and breakthroughs to spur the growth of new industry sectors.

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