BALANCE SHEETS (USD $)	Dec. 31, 2011	Dec. 31, 2010
Current assets:
Cash and cash equivalents	$ 20,145,854	$ 1,138,916
Short-term investments	10,400,905	395,556
Refundable income taxes	0	0
Prepaid expenses and other current assets	961,726	492,184
Total current assets	31,508,485	2,026,656
Property and equipment (at cost, less accumulated depreciation of $643,472 and $1,046,758, respectively)	782,720	378,672
Other assets:
Security deposit on letter of credit	250,000	0
Deposits and other assets	72,629	76,796
Patent license fees, net	35,625	43,125
Total other assets	358,254	119,921
Total assets	32,649,459	2,525,249
Current liabilities:
Accounts payable - trade	4,010,203	4,548,586
Other accrued liabilities	2,031,934	2,124,189
Note payable - current portion	110,287	123,465
Total current liabilities	6,152,424	6,796,240
Common stock warrant liability	166,398	248,131
Note payable - non-current portion	71,602	56,403
Other liabilities - noncurrent	65,467	0
Total liabilities	6,455,891	7,100,774
Stockholders' (deficit) equity:
Common stock - $0.01 par value (75,000,000 shares authorized; 33,899,057and 14,091,370 shares issued and 33,186,325 and 13,331,096 shares outstanding at December 31, 2011 and 2010, respectively)	338,991	140,914
Additional paid-in capital	153,237,225	99,316,859
Accumulated other comprehensive loss	(276,700)	(18,367)
Accumulated deficit	(124,221,823)	(100,938,261)
Subtotal	29,077,693	(1,498,855)
Treasury stock, at cost (712,732 and 760,274 shares at December 31 2011 and 2010, respectively)	(2,884,125)	(3,076,670)
Total stockholders' equity (deficit)	26,193,568	(4,575,525)
Total liabilities and stockholders' equity (deficit)	$ 32,649,459	$ 2,525,249