Condensed Consolidated Balance Sheets (unaudited) - USD ($)	Mar. 31, 2024	Dec. 31, 2023
Current assets
Cash and cash equivalents	$ 267,493	$ 1,151,823
Accounts receivable, net	37,968	103,316
Prepaid expenses and other current assets	227,112	324,735
Total current assets	532,573	1,579,874
Property and equipment, net	1,192,774
Operating lease right-of-use assets	844,705
Finance lease right-of-use assets, net		138
Other noncurrent assets	302,262	302,262
Total assets	2,872,314	1,882,274
Current liabilities
Accounts payable	191,575	111,149
Accrued compensation and benefits	47,828	127,601
Accrued liabilities	378,586	135,476
Deferred revenue	8,571	25,926
EIB loan guaranty	10,920,451	10,873,867
Short-term finance lease liabilities		280
Short-term operating lease liabilities	154,117	147,943
Total current liabilities	11,701,128	11,422,242
Long-term operating lease liabilities, net of short-term amount	1,981,428	2,021,616
Total liabilities	13,682,556	13,443,858
Stockholders’ deficit
Common stock, $0.01 par value; 100,000,000 shares authorized; 1,303,739 and 1,282,686 shares issued and outstanding at March 31, 2024 and December 31, 2023, respectively	13,037	12,827
Additional paid-in capital	294,380,054	293,991,529
Accumulated deficit	(305,205,335)	(305,493,302)
Accumulated other comprehensive loss		(75,138)
Total stockholders’ deficit	(10,810,242)	(11,561,584)
Total liabilities and stockholders’ deficit	2,872,314	1,882,274
Preferred Stock Series D [Member]
Stockholders’ deficit
Preferred stock, value	2	2,500
Preferred Stock Series E [Member]
Stockholders’ deficit
Preferred stock, value	$ 2,000