Note 11 - Income Taxes (Tables)

12 Months Ended

Dec. 31, 2022

Notes Tables

Summary of Operating Loss Carryforwards [Table Text Block]

Year Ending December 31,	Amount
2024	$	66,000
2028		7,000
2030		160,000
2031		73,000
2032		48,000
2034		727,000
2035		1,969,000
2036		2,867,000
2037		2,481,000
Indefinite		33,997,000
Total	$	42,395,000

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

	2022			2021
Deferred tax assets:
Net operating loss carryforwards	$	10,761,000		$	9,570,000
Tax credits		10,354,000			8,104,000
Impairment allowances		19,000			13,000
Stock-based compensation		45,000			-
Other		105,000			99,000
Accrued bonuses		245,000			-
Research and development expenses, net		1,642,000			-
Less valuation allowance		(23,167,000	)		(17,703,000	)
Deferred tax asset, net of valuation		4,000			83,000
Deferred tax liabilities:
Property and equipment		(4,000	)		(8,000	)
Stock-based compensation		-			(75,000	)
Deferred tax liabilities		(4,000	)		(83,000	)
Net tax assets	$	-		$	-

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

	2022			2021
Tax benefit (expense) at Federal statutory rate		21	%		21	%
Effect of State taxes		3	%		3	%
Effect of tax rate change		-	%		3	%
Tax credits		15	%		16	%
Nondeductible expenses		(3	)%		(3	)%
Valuation allowance – deferred tax assets		(36	)%		(39	)%
Total tax benefit (provision)	$	-		$	-