Note 12 - Segments - Segments (Details) - USD ($)	3 Months Ended						9 Months Ended
	Sep. 30, 2023	Jun. 30, 2023	Mar. 31, 2023	Sep. 30, 2022	Jun. 30, 2022	Mar. 31, 2022	Sep. 30, 2023	Sep. 30, 2022	Dec. 31, 2022
Revenue	$ 715,056			$ 455,827			$ 1,445,061	$ 1,141,986
Net loss	(3,163,450)	$ (3,923,368)	$ (3,421,802)	(4,059,484)	$ (10,391,324)	$ (3,370,715)	(10,508,620)	(17,821,524)
Assets	18,166,868						18,166,868		$ 25,734,644
Operating Segments [Member] | Pittsburgh [Member]
Revenue	417,096			172,637			441,567	266,642
Net loss	(674,952)			(1,076,508)			(3,428,644)	(10,891,767)
Assets	3,422,462						3,422,462		1,055,228
Operating Segments [Member] | Eagan [Member]
Revenue	259,530			253,751			866,535	809,875
Net loss	(189,031)			(109,408)			(756,115)	(259,444)
Assets	1,336,101						1,336,101		946,394
Operating Segments [Member] | Birmingham [Member]
Revenue	38,430			29,439			136,959	64,580
Net loss	(415,083)			(407,622)			(1,483,222)	(1,206,550)
Assets	1,116,990						1,116,990		1,353,434
Corporate, Non-Segment [Member]
Revenue	0			0			0	889
Net loss	(1,884,384)			$ (2,465,946)			(4,840,639)	$ (5,463,763)
Assets	$ 12,291,315						$ 12,291,315		$ 22,379,588