Consolidated Balance Sheets - USD ($)	Dec. 31, 2019	Dec. 31, 2018
Current assets:
Cash and cash equivalents	$ 7,619,748	$ 8,432,600
Short-term investments available-for-sale, at fair value	25,410,222	22,681,049
Accounts receivable	3,164,176	5,012,678
Inventory, net of allowance of $39,403 at both December 31, 2019 and December 31, 2018	1,269,667	1,306,609
Restricted cash, current	3,270,247
Prepaid expenses and other	633,522	519,002
Total current assets	41,367,582	37,951,938
Restricted cash, non-current		3,270,247
Operating lease right-of-use assets	1,209,145
Property and equipment, net	2,240,133	2,373,790
Other non-current assets	302,409	175,305
Total assets	45,119,269	43,771,280
Current liabilities:
Accounts payable	1,662,583	1,849,921
Accrued liabilities	1,870,296	3,358,465
Contract liabilities - current	426,014	332,711
NuvoGen obligation - current	1,152,233	1,290,234
Convertible note - current, net of debt issuance costs	2,987,667
Operating lease liabilities - current	758,932
Other current liabilities	41,134	186,043
Total current liabilities	8,898,859	7,017,374
NuvoGen obligation - non-current, net of discount	4,498,777	5,702,519
Convertible note - non-current, net of debt issuance costs		2,974,213
MidCap Term Loan payable - net of discount and debt issuance costs	6,871,545	6,704,641
Operating lease liabilities - non-current	636,340
Other non-current liabilities	244,114	280,471
Total liabilities	21,149,635	22,679,218
Commitments and Contingencies (Note 15)
Stockholders’ equity:
Common stock, $0.001 par value; 200,000,000 shares authorized at December 31, 2019 and December 31, 2018, 58,090,233 shares issued and outstanding at December 31, 2019 and 28,585,449 shares issued and outstanding at December 31, 2018	58,090	28,585
Additional paid-in-capital	194,234,151	172,086,909
Accumulated other comprehensive loss	(4,964)	(3,453)
Accumulated deficit	(170,317,643)	(151,019,979)
Total stockholders’ equity	23,969,634	21,092,062
Total liabilities and stockholders' equity	$ 45,119,269	$ 43,771,280