Arrowhead Research Partners with Rinzler Lab at University of Florida to Make Flexible Thin Film Transistors Aimed at the Estimated $20 Billion Flexible Electronics Market

PASADENA, California – August 3, 2006 – Arrowhead Research Corporation (Nasdaq: ARWR), announced today that it will begin a collaboration with Dr. Andrew Rinzler to further develop flexible electronic devices made at the University of Florida. Arrowhead will have the first option to exclusively license and commercialize the technology.

"Dr. Rinzler has made new thin film transistors using carbon nanotubes that could break open this field," said R. Bruce Stewart, CEO and Chairman of Arrowhead. "We look forward to working with him to optimize his devices and put together a plan for commercialization."

Thin film transistors (TFTs) can be used to make products such as low cost RFID (radio frequency ID) tags, flexible displays, and electronic paper. Further, unlike state of the art electronics manufacturing facilities which cost billions of dollars, flexible electronics are likely to be produced with low cost ink-jet printing technologies. According to estimates from NanoMarkets, the total market for products based on thin film transistors could reach over $20 billion by 2012.

Dr. Rinzler is a professor in the Physics Department at the University of Florida, specializing in carbon nanotube processing and devices. In addition to his novel nanotube-based transistor architecture, he also developed pure homogeneous nanotube films as transparent conductors. As a post doctoral fellow in Rick Smalley's Laboratory, Dr. Rinzler was among the early researchers to develop the field of carbon nanotubes. He was listed by Thomson ISI in the top 10 of the most cited authors in Nanotechnology for the decade 1992-2002. He is coauthor on over 65 refereed publications, with 20 patents issued and several applications in process.

Under the agreement with the University of Florida, Arrowhead will provide $647,000 over a two year period to develop optimized TFT devices and prototypes of TFT arrays.

About Arrowhead Research Corporation

Arrowhead Research Corporation (www.arrowheadresearch.com) 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.

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Contacts

Virginia Dadey; Vice President, Investor Relations
Telephone: 212.541.3707
Email: vdadey@arrowres.com