Note 7 - Stockholders' Equity (Details Textual) - USD ($)
 12 Months Ended
Feb. 11, 2021
Sep. 29, 2020
Dec. 31, 2021
Dec. 31, 2020
Sep. 30, 2021
Sep. 28, 2021
Jun. 01, 2021
Sep. 24, 2020
Jun. 26, 2020
Preferred Stock, Par or Stated Value Per Share (in dollars per share)     $ 0.01 $ 0.01          
Proceeds from Issuance or Sale of Equity, Gross   $ 12,800,000              
Proceeds from Issuance or Sale of Equity, Total   $ 11,200,000              
Number of Common Stock Securities Called by Each Unit (in shares)   1              
Deferred Compensation Liability Conversion to Equity, Amount   $ 1,500,000   $ 1,500,000          
Deferred Compensation Liability Conversion to Equity, Conversion Price (in dollars per share)   $ 5              
Stock Issued During Period, Shares, Cancellation of Accrued Compensation (in shares)   300,001   300,001          
Stock Issued During Period, Shares, Conversion of Convertible Securities (in shares)   177,626              
Stock Issued During Period, Shares, New Issues (in shares) 1,644,000                
Stock Issued During Period, Value, New Issues $ 10,300,000   $ 9,408,920 $ 11,158,496          
Proceeds from Issuance of Common Stock $ 9,400,000                
Proceeds from Warrant Exercises     $ 3,404,156 $ 2,500          
Stock Issued During Period, Shares, Issued for Services (in shares)     13,707 26,581          
Conversion of Stock, Shares Issued (in shares)       716,790          
Share-based Compensation Arrangement by Share-based Payment Award, Purchase Price of Common Stock, Percent       110.00%          
Share-based Compensation Arrangement by Share-based Payment Award, Expiration Period (Year)       10 years          
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Weighted Average Grant Date Fair Value (in dollars per share)     $ 2.87 $ 1.12          
Prepaid Expense, Value of Stock Issued for Services During Period     $ 19,947            
Expense Related To Consulting And Investment Banking Agreements [Member]                  
Share-based Payment Arrangement, Expense     100,560 $ 45,733          
Share-based Payment Arrangement, Option [Member]                  
Share-based Payment Arrangement, Expense     269,427 $ 18,730          
Share-based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Amount, Total     $ 1,420,144            
Share-based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Period for Recognition (Year)     2 years 73 days            
Stock Incentive Plan 2020 [Member]                  
Common Stock, Capital Shares Reserved for Future Issuance (in shares)         1,500,000        
Conversion of Series H, Series I, and Series J Preferred Stock into Common Stock [Member]                  
Conversion of Stock, Shares Issued (in shares)       716,790          
Conversion from Convertible Debentures to Conversion Units [Member]                  
Debt Conversion, Converted Instrument, Principal and Interest, Amount   $ 1,214,667              
Conversion Warrants [Member]                  
Class Of Warrant Or Right, Issued During Period (in shares)   2,560,000              
Conversion Warrants [Member] | Conversion from Convertible Debentures to Conversion Units [Member]                  
Debt Conversion, Converted Instrument, Warrants or Options Issued (in shares)   303,668              
Unit Warrant [Member]                  
Class of Warrant or Right, Number of Securities Called by Each Warrant or Right (in shares)   1              
Class of Warrant or Right, Exercise Price of Warrants or Rights (in dollars per share)   $ 5 $ 5            
Warrants and Rights Outstanding, Term (Year)   5 years              
Class of Warrant or Right, Exercised During Period (in shares)     740,034            
Proceeds from Warrant Exercises, Gross     $ 3,700,000            
Proceeds from Warrant Exercises     $ 3,400,000            
Stock Issued During Period, Shares, Warrants Exercised (in shares)     27,004            
Pre-Funded Warrants [Member]                  
Class of Warrant or Right, Number of Securities Called by Each Warrant or Right (in shares)   1              
Pre-Funded Warrants [Member] | Conversion from Convertible Debentures to Conversion Units [Member]                  
Debt Conversion, Converted Instrument, Warrants or Options Issued (in shares)   126,042   126,042          
Management Warrant [Member]                  
Number of Warrants Called by Each Unit (in shares)   1              
Class of Warrant or Right, Number of Securities Called by Warrants or Rights (in shares)   300,001              
Stock Purchase Warrants [Member]                  
Class of Warrant or Right, Exercised During Period (in shares)     215,672 54,557          
Stock Issued During Period, Shares, Warrants Exercised (in shares)     149,705 36,902          
June 2020 Warrants [Member]                  
Class of Warrant or Right, Exercise Price of Warrants or Rights (in dollars per share)   $ 5             $ 10
Warrants and Rights Outstanding, Term (Year)                 5 years
Class of Warrant or Right, Number of Securities Called by Warrants or Rights (in shares)                 120,000
Conversion of Convertible Debenture [Member]                  
Class of Warrant or Right, Number of Securities Called by Warrants or Rights (in shares)   303,668              
Unit Warrants [Member]                  
Class of Warrant or Right, Number of Securities Called by Warrants or Rights (in shares)   2,560,000              
Unit Warrants [Member] | Conversion from Convertible Debentures to Conversion Units [Member]                  
Debt Conversion, Converted Instrument, Warrants or Options Issued (in shares)       303,668          
Representative Warrants 2020 [Member]                  
Class of Warrant or Right, Exercise Price of Warrants or Rights (in dollars per share)     $ 5.5         $ 5.50  
Warrants and Rights Outstanding, Term (Year)   3 years 180 days              
Class of Warrant or Right, Number of Securities Called by Warrants or Rights (in shares)   128,000              
Representative Warrants 2021 [Member]                  
Class of Warrant or Right, Exercise Price of Warrants or Rights (in dollars per share) $ 6.875   6.875            
Warrants and Rights Outstanding, Term (Year) 3 years 180 days                
Class of Warrant or Right, Number of Securities Called by Warrants or Rights (in shares) 72,000                
Warrants 2021 [Member]                  
Class of Warrant or Right, Exercise Price of Warrants or Rights (in dollars per share)     $ 13     $ 13      
Warrants and Rights Outstanding, Term (Year)           5 years      
Class of Warrant or Right, Number of Securities Called by Warrants or Rights (in shares)           100,000      
Series B Convertible Preferred Stock [Member]                  
Preferred Stock, Shares Outstanding, Ending Balance (in shares)     0 100     100    
Preferred Stock, Par or Stated Value Per Share (in dollars per share)     $ 1,000 $ 1,000          
Capital Units Tranche One [Member] | Capital Units [Member]                  
Number of Common Stock Securities Called by Each Unit (in shares)   1