Note 4 - Property and Equipment - Property and Equipment (Details) - USD ($)	Dec. 31, 2019	Dec. 31, 2018
Property and equipment, gross	$ 763,799	$ 767,470
Less: accumulated depreciation	(511,433)	(417,189)
Property and equipment, net	252,366	350,281
Laboratory Equipment [Member]
Property and equipment, gross	182,357	182,357
Furniture and Fixtures [Member]
Property and equipment, gross	151,442	155,113
Leasehold Improvements [Member]
Property and equipment, gross	$ 430,000	$ 430,000

Amount of accumulated depreciation, depletion and amortization for physical assets used in the normal conduct of business to produce goods and services.

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Amount before accumulated depreciation, depletion and amortization of physical assets used in the normal conduct of business and not intended for resale. Examples include, but are not limited to, land, buildings, machinery and equipment, office equipment, and furniture and fixtures.

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