Note 10 - Net Loss Per Share (Tables)

12 Months Ended

Dec. 31, 2020

Notes Tables

Schedule of Earnings Per Share, Basic and Diluted [Table Text Block]

	Year Ended December 31,
	2020			2019
Numerator
Net loss	$	(17,827,952	)	$	(17,239,777	)
Deemed dividend attributable to preferred stock		(4,502,799	)		-
Net loss attributable to common shareholders	$	(22,330,751	)	$	(17,239,777	)
Denominator
Weighted average common shares outstanding used to compute net loss per share, basic and diluted		11,308,532			8,496,964
Net loss per share of common stock, basic and diluted:	$	(1.97	)	$	(2.03	)

Schedule of Antidilutive Securities Excluded from Computation of Earnings Per Share [Table Text Block]

	Year Ended December 31,
	2020		2019
Options to purchase common stock		6,138,485		3,013,370
Series B convertible preferred stock		227,010		258,230
Warrants to purchase common stock		2,270,848		1,637,013
		8,636,343		4,908,613