Condensed Consolidated Balance Sheets - USD ($)	Jun. 30, 2019	Dec. 31, 2018
Current assets:
Cash and cash equivalents	$ 11,813,589	$ 8,432,600
Short-term investments available-for-sale, at fair value	9,753,727	22,681,049
Accounts receivable	3,981,103	5,012,678
Inventory, net of allowance of $39,403 at both June 30, 2019 and December 31, 2018	1,160,682	1,306,609
Prepaid expenses and other	1,069,180	568,209
Total current assets	27,778,281	38,001,145
Restricted cash	3,270,247	3,270,247
Deferred offering costs	198,088	59,030
Deferred MidCap revolving loan costs	59,086	67,068
Operating lease right-of-use assets	1,394,664
Property and equipment, net	2,424,625	2,373,790
Total assets	35,124,991	43,771,280
Current liabilities:
Accounts payable	3,357,343	1,849,921
Accrued liabilities	1,499,510	3,358,465
Contract liabilities - current	486,994	332,711
NuvoGen obligation - current	1,286,152	1,290,234
MidCap Term Loan payable - current	583,333
Operating lease liabilities - current	682,863
Other current liabilities	63,344	186,043
Total current liabilities	7,959,539	7,017,374
NuvoGen obligation - non-current, net of discount	5,044,263	5,702,519
Convertible note, related party - net of debt issuance costs	2,980,940	2,974,213
MidCap Term Loan payable – non-current, net of discount and debt issuance costs	6,194,422	6,704,641
Operating lease liabilities - non-current	976,786
Other non-current liabilities	299,049	280,471
Total liabilities	23,454,999	22,679,218
Commitments and Contingencies (Note 16)
Stockholders’ equity:
Common stock, $0.001 par value; 200,000,000 shares authorized at June 30, 2019 and December 31, 2018, 28,707,047 shares issued and outstanding at June 30, 2019 and 28,585,449 shares issued and outstanding at December 31, 2018	28,707	28,585
Additional paid-in-capital	172,831,416	172,086,909
Accumulated other comprehensive loss	(2,036)	(3,453)
Accumulated deficit	(161,188,095)	(151,019,979)
Total stockholders’ equity	11,669,992	21,092,062
Total liabilities and stockholders’ equity	$ 35,124,991	$ 43,771,280