Consolidated Balance Sheets - USD ($)	Dec. 31, 2018	Dec. 31, 2017
Current assets:
Cash and cash equivalents	$ 8,432,600	$ 9,968,600
Short-term investments available-for-sale, at fair value	22,681,049
Accounts receivable	5,012,678	6,356,268
Inventory, net of allowance of $39,403 and $62,142 at December 31, 2018 and 2017, respectively	1,306,609	1,180,521
Prepaid expenses and other	568,209	443,068
Total current assets	38,001,145	17,948,457
Restricted cash - non-current	3,270,247
Deferred offering costs	59,030	2,953
Deferred MidCap revolving loan costs	67,068
Property and equipment, net	2,373,790	3,304,890
Total assets	43,771,280	21,256,300
Current liabilities:
Accounts payable	1,849,921	2,438,798
Accrued liabilities	3,358,465	3,746,786
Contract liabilities - current	332,711	665,882
NuvoGen obligation - current	1,290,234	496,442
Growth Term Loan payable - net of discount and debt issuance costs		5,793,599
Other current liabilities	186,043	200,460
Total current liabilities	7,017,374	13,341,967
NuvoGen obligation - non-current, net of discount	5,702,519	7,520,913
Convertible note, related party - net of debt issuance costs	2,974,213	2,960,760
MidCap Term Loan payable - net of discount and debt issuance costs	6,704,641
Other non-current liabilities	280,471	492,197
Total liabilities	22,679,218	24,315,837
Commitments and Contingencies (Note 14)
Stockholders’ equity (deficit):
Common stock, $0.001 par value; 200,000,000 shares authorized at December 31, 2018 and December 31, 2017, 28,585,449 shares issued and outstanding at December 31, 2018 and 13,929,763 shares issued and outstanding at December 31, 2017	28,585	13,929
Additional paid-in-capital	172,086,909	131,492,595
Accumulated other comprehensive loss	(3,453)
Accumulated deficit	(151,019,979)	(134,566,061)
Total stockholders’ equity (deficit)	21,092,062	(3,059,537)
Total liabilities and stockholders' equity (deficit)	$ 43,771,280	$ 21,256,300