Prepaid expenses and other current assets (Details) - USD ($)	Dec. 31, 2019	Dec. 31, 2018
Prepaid Expense and Other Assets, Current [Abstract]
Prepaid insurance	$ 100,374	$ 90,754
Prepaid supplies	26,892	19,422
Prepaid professional services	97,513	38,375
Prepaid rent and lease deposits	25,581	13,508
Asset held for sale	98,000	0
Other current assets	42,802	153,910
Total prepaid expenses and other current assets	$ 391,162	$ 315,969