Balance Sheets (Unaudited) (USD $)	Jun. 30, 2012	Dec. 31, 2011
Current assets:
Cash and cash equivalents	$ 11,708,110	$ 20,145,854
Short-term investments	12,287,271	10,400,905
Other current assets	939,163	961,726
Total current assets	24,934,544	31,508,485
Property and equipment (at cost, less accumulated depreciation of $747,631 and $643,472, respectively)	1,049,775	782,720
Other assets:
Deposits, deferred fees and other assets	520,047	322,629
Patent licensing fees, net	31,875	35,625
Total other assets	551,922	358,254
Total assets	26,536,241	32,649,459
Current liabilities:
Accounts payable	4,305,660	4,010,203
Accrued liabilities	1,890,412	2,031,934
Notes payable - current portion	493,949	110,287
Total current liabilities	6,690,021	6,152,424
Common stock warrant liability	536,121	166,398
Notes payable – non-current portion	4,605,384	71,602
Other liabilities	128,381	65,467
Total liabilities	11,959,907	6,455,891
Stockholders' equity:
Common stock, $0.01 par value; 75,000,000 shares authorized and 33,899,057 shares issued at June 30, 2012 and December 31, 2011 and 33,227,679 and 33,186,325 shares outstanding at June 30, 2012 and December 31, 2011, respectively	338,991	338,991
Additional paid-in capital	153,867,900	153,237,225
Accumulated other comprehensive loss	(315,600)	(276,700)
Accumulated deficit	(136,598,303)	(124,221,823)
Subtotal	17,292,988	29,077,693
Treasury stock, at cost (671,378 and 712,732 shares at June 30, 2012 and December 31, 2011, respectively)	(2,716,654)	(2,884,125)
Total stockholders' equity	14,576,334	26,193,568
Total liabilities and stockholders' equity	$ 26,536,241	$ 32,649,459