Note 9 - Stock-based Compensation Expense - Compensation Expense (Details) - USD ($)	3 Months Ended		9 Months Ended
	Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2022	Sep. 30, 2021
Stock-based compensation	$ 118,548	$ 105,491	$ 307,379	$ 217,942
Cost of Revenue [Member]
Stock-based compensation	9,221	7,715	26,100	7,715
Research and Development Expense [Member]
Stock-based compensation	16,367	3,972	42,684	3,972
Selling and Shipping [Member]
Stock-based compensation	7,508	4,371	18,305	4,371
General and Administrative [Member]
Stock-based compensation	$ 85,452	$ 89,433	$ 220,290	$ 201,884