Condensed Consolidated Statements of Cash Flows - USD ($)	9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017
Cash flows from operating activities
Net loss	$ (9,635,722)	$ (12,454,647)
Adjustments to reconcile net loss to net cash used in operating activities
Depreciation and amortization	508,162	499,651
Noncash interest expense	108,011	65,511
Share-based compensation	658,731	722,304
Gain on sale of equipment	(5,253)	0
Change in fair value of warrant liabilities	(8,070)	(124,139)
Unamortized discount on bridge loan at repayment	0	85,932
Changes in operating assets and liabilities:
Accounts receivable	492,444	72,466
Inventory	3,179	231,239
Other assets	(164,346)	(337,999)
Accounts payable	(493,971)	(293,388)
Accrued compensation and other liabilities	174,560	337,562
Deferred revenue	(14,119)	(6,158)
Net cash used in operating activities	(8,376,394)	(11,201,666)
Cash flows from investing activities
Purchases of property and equipment	(41,910)	(142,687)
Proceeds from sale of equipment	10,440	0
Net cash used in investing activities	(31,470)	(142,687)
Cash flows from financing activities
Proceeds from issuance of common stock, net of issuance costs	597,743	3,426,050
Proceeds from issuance of units, net of selling costs	10,728,132	8,754,882
Proceeds from debt, net of issuance costs	381,253	1,168,222
Proceeds from exercise of stock options	0	48,179
Payments on debt	(299,256)	(1,146,287)
Payments on capital lease obligations	(177,092)	(156,161)
Net cash provided by financing activities	11,230,780	12,094,885
Effects of exchange rates on cash	7,419	(13,825)
Net increase in cash, cash equivalents and restricted cash	2,830,335	736,707
Cash, cash equivalents and restricted cash at beginning of period	2,090,551	4,360,704
Cash, cash equivalents and restricted cash at end of period	4,920,886	5,097,411
Supplemental disclosure of cash flow information
Cash paid for interest	32,442	108,463
Supplemental disclosures of noncash investing and financing activities:
Shares issued to settle obligations	272,610	110,000
Issuance of placement agent warrant	0	93,677
Property and equipment acquired through capital lease	585,278	0
Conversion of accounts payable to capital lease	156,775	0
Unpaid deferred offering costs	$ 0	$ 48,398