Consolidated Statements of Cash Flows - USD ($)	6 Months Ended
	Jun. 30, 2015	Jun. 30, 2014
Cash flows from operating activities
Net loss	$ (3,724,000)	$ 2,566,000
Adjustments required to reconcile net income (loss) from operations to net cash used in operating activities:
Change in fair value of warrant liability	86,000	(2,166,000)
Change in fair value of Preferred B derivative liability	(1,652,000)	(6,682,000)
Warrants issued to placement agents	213,000
Amortization of patents	15,000	15,000
Depreciation	117,000	86,000
Stock-based compensation	105,000	468,000
Changes in operating assets and liabilities net of acquisitions:
Accounts receivable	100,000	(128,000)
Accounts payable, accrued expenses and other	181,000	(675,000)
Accrued severance	(234,000)
Prepaid expenses and other current assets	(174,000)	(229,000)
Net cash used in operating activities	(4,967,000)	(6,745,000)
Investing activities:
Purchases of property and equipment	(44,000)	(1,060,000)
Net cash provided by (used in) investing activities	(44,000)	(1,060,000)
Financing activities:
Proceeds from warrant exercises	397,000
Proceeds from issuance of common stock, net	12,384,000
Net cash provided by financing activities	12,781,000
Net increase (decrease) in cash and cash equivalents	7,770,000	(7,805,000)
Cash and cash equivalents, beginning of period	6,581,000	20,355,000
Cash and cash equivalents, end of period	14,351,000	12,550,000
Supplemental schedule of non-cash financing activities:
Accretion of Series B redeemable convertible preferred stock	$ 2,166,000	$ 632,000
Fair value of warrant liability upon issuance	4,210,000