Note 9 - Income Taxes (Tables)

12 Months Ended

Dec. 31, 2019

Notes Tables

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

	2019			2018
Deferred tax assets:
Net operating loss carryforward	$	15,328,336		$	16,681,908
Research and development tax credit carryforward		1,122,536			1,063,877
Stock-based compensation expense		1,877,284			1,808,509
Accrued salaries and directors’ fees		450,503			315,246
Depreciation		8,571			8,414
Total deferred tax assets		18,787,230			19,879,954
Deferred tax liabilities		-			-
Net deferred tax assets		18,787,230			19,879,954
Valuation allowance		(18,787,230	)		(19,879,954	)
Net deferred tax asset after reduction for valuation allowance	$	-0-		$	-0-

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

	2019			2018
U.S. federal statutory rate applied to pretax loss	$	(497,833	)	$	(537,620	)
Permanent differences		278			549
Research and development credits		(47,053	)		(53,884	)
Change in valuation allowance		544,308			590,955
Reported income tax expense	$	-0-		$	-0-