BALANCE SHEETS - USD ($) $ in Thousands	Dec. 31, 2022	Dec. 31, 2021
Current assets:
Cash and cash equivalents	$ 4,775	$ 9,326
Accounts receivable, net	113	77
Prepaid expenses	378	230
Inventory, net	853	1,001
Total current assets	6,119	10,634
Right to use assets, operating leases	347	511
Property and equipment, net	294	334
Other noncurrent assets	22	22
Total assets	6,782	11,501
Current liabilities:
Short-term debt	0	32
Accounts payable	540	333
Accrued expenses	560	578
Current portion of operating lease liability	180	164
Deferred revenue	44	0
Total current liabilities	1,324	1,107
Operating lease liability, less current portion	179	359
Total liabilities	1,503	1,466
Commitments and contingencies (see notes)
Stockholders’ equity:
Preferred stock, $0.001 par value, 10,000,000 shares authorized, none issued and outstanding	0	0
Common stock, $0.001 par value, 100,000,000 shares authorized, 809,648 and 610,364 shares issued and outstanding as of December 31, 2022 and 2021, respectively	1	1
Additional paid-in capital	127,481	122,542
Accumulated deficit	(122,203)	(112,508)
Total stockholders’ equity	5,279	10,035
Total liabilities and stockholders’ equity	$ 6,782	$ 11,501