3. Derivative financial instruments	3 Months Ended
Mar. 31, 2013
Derivative Instrument Detail [Abstract]
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 758,333 shares of the Company’s common stock as of March 31, 2013 and December 31, 2012 and are carried at fair value. The balance at March 31, 2013 of $64,459 compared to $57,634 at December 31, 2012. 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 March 31, 2013 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%.

3. Derivative financial instruments

3 Months Ended

Mar. 31, 2013

Derivative Instrument Detail [Abstract]

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 758,333 shares of the Company’s common stock as of March 31, 2013 and December 31, 2012 and are carried at fair value. The balance at March 31, 2013 of $64,459 compared to $57,634 at December 31, 2012.

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 March 31, 2013 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%.