Note 6 - Stock-Based Compensation Expense - Schedule of Stock-Based Compensation Expense (Details) - USD ($)	3 Months Ended	6 Months Ended
Jun. 30, 2022	Jun. 30, 2021	Jun. 30, 2022	Jun. 30, 2021
Total stock-based compensation expense	$ 207,178	$ 86,763	$ 412,329	$ 163,553
Share-Based Payment Arrangement, Option [Member]
Total stock-based compensation expense	190,191	56,190	380,382	112,380
Share-Based Payment Arrangement, Option [Member] \| Research and Development Expense [Member]
Total stock-based compensation expense	54,293	21,468	108,585	42,936
Share-Based Payment Arrangement, Option [Member] \| General and Administrative Expense [Member]
Total stock-based compensation expense	135,898	34,722	271,797	69,444
Restricted Stock [Member] \| General and Administrative Expense [Member]
Total stock-based compensation expense	$ 16,987	$ 30,573	$ 31,947	$ 51,173