6. Share-based Compensation (Tables)

6 Months Ended

Jun. 30, 2013

Notes to Financial Statements

Weighted average assumptions of share based payment

	Three Month Period Ended				Six Month Period Ended
	June 30,				June 30,
	2013		2012		2013		2012
Risk free interest rate		––		0.76%		––		0.80%
Dividend yield		––		0.0%		––		0.0%
Expected term (in years)		––		7		––		6.5
Volatility		––		104.95%		––		103.12%

Stock compensation expense

	Three Month Period Ended				Six Month Period Ended
	June 30,				June 30,
	2013		2012		2013		2012
Research and development costs	$	6,954	$	7,119	$	13,908	$	13,487
Sales and marketing costs		630		210		1,260		210
General and administrative costs		1,378		38,523		49,314		75,822
Cost of product sales		11,209		5,073		23,071		8,094
Total	$	20,171	$	50,925	$	87,553	$	97,613

Summary of stock option activity

	Six Month Period Ended
	June 30, 2013
				Wtd. Avg.
				Exercise
	Shares			Price
Outstanding at beginning of year		20,379,602		$	0.09
Granted		––			––
Exercised		(355,855	)		(0.08	)
Forfeited		(200,000	)		(0.16	)
Outstanding at June 30, 2013		19,823,747		$	0.09
Stock options exercisable at June 30, 2013		16,236,389		$	0.08