Consolidated Statements of Changes in Stockholders' Equity (Unaudited) - USD ($)	Preferred Stock - Series F [Member]	Common Stock [Member]	Additional Paid-in Capital [Member]	Accumulated Deficit [Member]	Total
Balance at Apr. 30, 2018		$ 17,591	$ 30,911,222	$ (18,228,552)	$ 12,700,261
Balance, shares at Apr. 30, 2018		17,590,574
Issuance of common stock for services		$ 19	76,489		76,508
Issuance of common stock for services, shares		19,319
Issuance of common stock for accrued services		$ 9	12,491		12,500
Issuance of common stock for accrued services, shares		9,191
Stock options granted for services			33,636		33,636
Net loss				(1,481,504)	(1,481,504)
Balance at Jul. 31, 2018		$ 17,619	31,033,838	(19,710,056)	11,341,401
Balance, shares at Jul. 31, 2018		17,619,084
Balance at Apr. 30, 2019		$ 19,861	33,408,056	(26,275,102)	7,152,815
Balance, shares at Apr. 30, 2019		19,860,625
Issuance of preferred stock and warrants for cash, net of offering cost	$ 1		2,401,201		2,401,202
Issuance of preferred stock and warrants for cash, net of offering cost, shares	1,250
Issuance of common stock for services		$ 21	24,979		25,000
Issuance of common stock for services, shares		21,534
Conversion of preferred stock into common stock		$ 1,080	(1,080)
Conversion of preferred stock into common stock, shares	(616)	1,080,707
Issuance of common stock for accrued services		$ 11	12,489		12,500
Issuance of common stock for accrued services, shares		10,684
Stock options granted for services			52,214		52,214
Stock-based compensation in connection with restricted common stock unit grants			52,682		52,682
Cancellation of common stock		$ (85)	85
Cancellation of common stock, shares		(85,000)
Deemed dividends - series F preferred stock			2,022,712	(2,022,712)
Net loss				(1,308,599)	(1,308,599)
Balance at Jul. 31, 2019	$ 1	$ 20,888	$ 37,973,338	$ (29,606,413)	$ 8,387,814
Balance, shares at Jul. 31, 2019	634	20,888,550