Note 4 - Derivative financial instruments	6 Months Ended
Jun. 30, 2012
Notes to Financial Statements
Derivative financial instruments	The balance sheet caption derivative liabilities consist of Warrants, issued in connection with the 2005 Laurus Financing Arrangement, and the 2006 Omnibus Amendment and Waiver Agreement with Laurus. These derivative financial instruments are indexed to an aggregate of 1,658,333 shares of the Company’s common stock as of March 31, 2012 and December 31, 2011 and are carried at fair value. The balance at June 30, 2012 and December 31, 2011 was $66,117 and $96,367 respectively. The valuation of the derivative warrant liabilities is determined using a Black Scholes Merton Model. Freestanding derivative instruments, consisting of warrants and options that arose from the Laurus financing are valued using the Black-Scholes-Merton valuation methodology because that model embodies all of the relevant assumptions that address the features underlying these instruments. Significant assumptions used in the Black Scholes models as of December 31, 2011 and 2010 included conversion or strike prices ranging from $0.10 - $1.10; historical volatility factors ranging from 123.01% - 183.73% based upon forward terms of instruments; and a risk free rate ranging from 0.27% - 3.36%.

Note 4 - Derivative financial instruments

6 Months Ended

Jun. 30, 2012

The balance sheet caption derivative liabilities consist of Warrants, issued in connection with the 2005 Laurus Financing Arrangement, and the 2006 Omnibus Amendment and Waiver Agreement with Laurus. These derivative financial instruments are indexed to an aggregate of 1,658,333 shares of the Company’s common stock as of March 31, 2012 and December 31, 2011 and are carried at fair value. The balance at June 30, 2012 and December 31, 2011 was $66,117 and $96,367 respectively.

The valuation of the derivative warrant liabilities is determined using a Black Scholes Merton Model. Freestanding derivative instruments, consisting of warrants and options that arose from the Laurus financing are valued using the Black-Scholes-Merton valuation methodology because that model embodies all of the relevant assumptions that address the features underlying these instruments. Significant assumptions used in the Black Scholes models as of December 31, 2011 and 2010 included conversion or strike prices ranging from $0.10 - $1.10; historical volatility factors ranging from 123.01% - 183.73% based upon forward terms of instruments; and a risk free rate ranging from 0.27% - 3.36%.