Balance Sheets - USD ($)	Dec. 31, 2017	Dec. 31, 2016
Current assets:
Cash and cash equivalents	$ 9,968,600	$ 7,507,659
Short-term investments available-for-sale, at fair value		4,304,901
Accounts receivable	6,356,268	1,377,441
Inventory, net of allowance of $62,142 at December 31, 2017 and $270,307 at December 31, 2016	1,180,521	1,511,053
Prepaid expenses and other	443,068	433,328
Total current assets	17,948,457	15,134,382
Deferred offering costs	2,953	49,630
Property and equipment, net	3,304,890	3,270,197
Total assets	21,256,300	18,454,209
Current liabilities:
Accounts payable	2,438,798	761,663
Accrued liabilities	3,746,786	1,670,286
Deferred revenue - current	665,882	335,659
NuvoGen obligation - current	496,442	604,751
Term loan payable - current, net of discount and debt issuance costs of $64,807 at December 31, 2017 and $0 at December 31, 2016	5,793,599	6,389,782
Other current liabilities	200,460	258,850
Total current liabilities	13,341,967	10,020,991
Term loan payable - non-current, net of discount and debt issuance costs of $0 at December 31, 2017 and $263,378 at December 31, 2016		5,389,137
NuvoGen obligation - non-current, net of discount	7,520,913	8,017,356
Convertible note, related party - net of debt issuance costs	2,960,760
Other non-current liabilities	492,197	619,587
Total liabilities	24,315,837	24,047,071
Commitments and Contingencies (Note 13)
Stockholders’ deficit:
Common stock, $0.001 par value; 200,000,000 shares authorized at December 31, 2017 and December 31, 2016; 13,929,763 shares issued and outstanding, at December 31, 2017; 7,939,967 and 7,938,571 shares issued and outstanding, respectively, at December 31, 2016	13,929	7,938
Additional paid-in-capital	131,492,595	110,081,334
Treasury stock, no shares as of December 31, 2017 and 1,396 shares as of December 31, 2016		(75,000)
Accumulated other comprehensive loss		(1,090)
Accumulated deficit	(134,566,061)	(115,606,044)
Total stockholders’ deficit	(3,059,537)	(5,592,862)
Total liabilities and stockholders' deficit	$ 21,256,300	$ 18,454,209

Carrying value as of the balance sheet date of liabilities incurred (and for which invoices have typically been received) and payable to vendors for goods and services received that are used in an entity's business. Used to reflect the current portion of the liabilities (due within one year or within the normal operating cycle if longer).

Name:	us-gaap_AccountsPayableCurrent
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Amount due from customers or clients, within one year of the balance sheet date (or the normal operating cycle, whichever is longer), for goods or services (including trade receivables) that have been delivered or sold in the normal course of business, reduced to the estimated net realizable fair value by an allowance established by the entity of the amount it deems uncertain of collection.