Note 4 - Equipment - Equipment (Details) - USD ($)	Dec. 31, 2019	Dec. 31, 2018
Equipment, gross	$ 141,058	$ 1,134,855
Accumulated depreciation	(125,544)	(1,107,108)
Equipment, net	15,514	27,747
Computer Equipment [Member]
Equipment, gross	98,307	186,456
Laboratory Equipment [Member]
Equipment, gross	39,651	448,198
Furniture and Fixtures [Member]
Equipment, gross	$ 3,100	$ 500,201

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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