Note 5 - Property and Equipment - Property and Equipment (Details) - USD ($)	Dec. 31, 2017	Dec. 31, 2016
Property and equipment, gross	$ 767,470	$ 319,647
Less: accumulated depreciation	(306,818)	(239,892)
Property and equipment, net	460,652	79,755
Laboratory Equipment [Member]
Property and equipment, gross	182,357	182,357
Furniture and Fixtures [Member]
Property and equipment, gross	155,113	137,290
Leasehold Improvements [Member]
Property and equipment, gross	$ 430,000

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

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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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.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
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-Subparagraph (b)
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+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
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