Note 11 - Income Taxes (Tables)

12 Months Ended

Dec. 31, 2014

Notes Tables

Schedule of Deferred Tax Assets and Liabilities [Table Text Block]

	2014			2013
Deferred tax assets:
Net operating loss carryforward	$	22,831,626		$	21,983,109
Research and development tax credit carryforward		825,896			799,248
Stock-based compensation expense		2,396,805			2,233,909
Total deferred tax assets		26,054,327			25,016,266
Deferred tax liabilities
Depreciation		(7,149	)		(13,386	)
Total deferred tax liabilities		(7,149	)		(13,386	)
Net deferred tax assets		26,047,178			25,002,881
Valuation allowance		(26,047,178	)		(25,002,881	)
	$	-0-		$	-0-

Schedule of Effective Income Tax Rate Reconciliation [Table Text Block]

	2014			2013			2012
U.S. federal statutory rate applied to pretax loss	$	(929,409	)	$	(776,881	)	$	(725,948	)
Permanent differences		1,734			3,138			2,674
Research and development credits		26,648			14,047			21,236
Change in valuation allowance		901,027			759,696			702,038
Reported income tax expense	$	-0-		$	-0-		$	-0-