Stockholders' equity (Details)				1 Months Ended	12 Months Ended			20 Months Ended
	Feb. 10, 2023	Sep. 02, 2022 USD ($)	May 16, 2022 $ / shares shares	Feb. 28, 2023 USD ($) $ / shares shares	Dec. 31, 2023 USD ($) Vote $ / shares shares	Dec. 31, 2022 USD ($) $ / shares shares	Dec. 31, 2021 USD ($) shares	Dec. 31, 2023 $ / shares shares	Jan. 26, 2024 USD ($)	Nov. 12, 2020 USD ($)
Common stock
Stock, shares authorized | shares					440,000,000			440,000,000
Common stock, shares authorized | shares					400,000,000	400,000,000		400,000,000
Common stock, par value (in dollars per share) | $ / shares					$ 0.001	$ 0.001		$ 0.001
Preferred stock, shares authorized | shares					40,000,000			40,000,000
Preferred stock, par value (in dollars per share) | $ / shares					$ 0.001			$ 0.001
Reverse stock split ratio	0.05
Number of voting rights per common share | Vote					1
Shelf Registration Statement
Maximum amount to be issued under universal shelf registration statement | $										$ 350,000,000.0
Proceeds from issuance of common stock | $					$ 5,788,918	$ 682,973	$ 1,538,645
Common stock issuance costs | $					$ 648,928
Common Stock
Common stock
Conversion of preferred stock into common stock (in shares) | shares								1,446,701
Series A Convertible Preferred Stock
Common stock
Conversion of preferred stock into common stock (in shares) | shares						2,893,403		2,893,403
Number of shares remained to be converted into common stock | shares					56,227			56,227
Issuance of preferred stock upon acquisition of Atrin (in shares) | shares						2,949,630
Atrin Pharmaceuticals, Inc | Common Stock
Common stock
Common stock, par value (in dollars per share) | $ / shares			$ 0.001
Issuance of stock upon acquisition of Atrin (in shares). | shares			55,869
Atrin Pharmaceuticals, Inc | Series A Convertible Preferred Stock
Common stock
Issuance of stock upon acquisition of Atrin (in shares). | shares			2,949,630
Preferred stock conversion ratio			10
2020 Shelf Registration Statement
Shelf Registration Statement
Shares issued | shares				1,050,000
Issue price per share | $ / shares				$ 5.25
Proceeds from issuance of common stock | $				$ 4,900,000
Common stock issuance costs | $				$ 600,000
ATM offering
Common stock
Number of shares issued | shares					26,302	38,481	18,338
Commission payable as a percentage of gross proceeds from sale of common stock under ATM offering		3.00%
Shelf Registration Statement
Maximum amount to be issued under at-the-market offering program | $		$ 14,744,728
Proceeds from issuance of common stock | $					$ 300,000	$ 700,000	$ 1,500,000
2024 Shelf Registration Statement
Shelf Registration Statement
Maximum amount to be issued under universal shelf registration statement | $									$ 150,000,000
Maximum amount to be issued under at-the-market offering program | $									1,000,000
Maximum amount to be issued under at-the-market offering program, supplement | $									2,000,000
2024 ATM offering | HCW
Shelf Registration Statement
Maximum amount to be issued under at-the-market offering program | $									$ 2,000,000