Statements of Stockholders' Equity - USD ($)	Total	Common Stock [Member]	Additional Paid-In Capital [Member]	Accumulated Deficit [Member]
Beginning Balance at Dec. 31, 2016	$ 3,787,638	$ 1,235	$ 62,595,546	$ (58,809,143)
Beginning Balance, Shares at Dec. 31, 2016		12,350,360
Stock-based compensation expense	1,819,431		1,819,431
Issuance of common stock from employee stock purchase plan	$ 134,753	$ 7	134,746
Issuance of common stock from employee stock purchase plan, Shares	75,529	75,529
Issuance of common stock from warrant exercise		$ 21	(21)
Issuance of common stock from warrant exercise, Shares		211,860
Issuance of common stock, net	$ 7,254,348	$ 278	7,254,070
Issuance of common stock, shares net		2,775,861
Reclassification of warrant liability due to warrant amendment and exercise	1,399,091		1,399,091
Net loss	(12,229,512)			(12,229,512)
Ending Balance at Dec. 31, 2017	$ 2,165,749	$ 1,541	73,202,863	(71,038,655)
Ending Balance, Shares at Dec. 31, 2017	15,413,610	15,413,610
Stock-based compensation expense	$ 1,539,469		1,539,469
Issuance of common stock from employee stock purchase plan	$ 47,057	$ 3	47,054
Issuance of common stock from employee stock purchase plan, Shares	28,869	28,869
Issuance of common stock, net	$ 4,571,240	$ 199	4,571,041
Issuance of common stock, shares net		1,985,054
Reclassification of warrant liability due to warrant amendment and exercise	3,267,885		3,267,885
Net loss	(7,566,080)			(7,566,080)
Ending Balance at Dec. 31, 2018	$ 4,025,320	$ 1,743	$ 82,628,312	$ (78,604,735)
Ending Balance, Shares at Dec. 31, 2018	17,427,533	17,427,533