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    Units in Mass Transfer k_t model
- dirk
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                5 years 1 week ago                #1
        by dirk
    
    
 	
					
			
				    
            
            
            
            
            
                                
    
                    
    
        Units in Mass Transfer k_t model was created by dirk            
    
        I have a question about the units in the differential equations for the mass transfer model with k_t parameter. Although the units for all quantities are displayed when clicking on the info button, there seems to be something wrong. The left side of the first equation is in M/s while the other terms in that equation and also in the other two equations are in RU/s.
How is this handled when doing a calclulation? Can one translate molar concentrations to RU using the 10e9 factor which appears in the formulas of the k_m model?
    How is this handled when doing a calclulation? Can one translate molar concentrations to RU using the 10e9 factor which appears in the formulas of the k_m model?
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- Arnoud
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                5 years 1 week ago         -  4 years 11 months ago        #2
        by Arnoud
    
    
    
            
            
            
            
                                
    
                    
    
        Replied by Arnoud on topic Units in Mass Transfer k_t model            
    
        Hi,
It is something like that.
Since the response is proportional to the molecular weight of the analyte, and, for dextran chips the relation of 1 RU = 1 pg/mm2 is valid. You can convert the response in RU to Molar.
1 RU = 1 pg/mm2 = 10 g/L → g/L divided by Mr (g/mole) → mole/L = M.
Main problem with writing the formula in concentrations (e.g. [LA]) is that we actual mean Response in RU. But this is how most of the formulas are published.
Kind regards
Arnoud
    It is something like that.
Since the response is proportional to the molecular weight of the analyte, and, for dextran chips the relation of 1 RU = 1 pg/mm2 is valid. You can convert the response in RU to Molar.
1 RU = 1 pg/mm2 = 10 g/L → g/L divided by Mr (g/mole) → mole/L = M.
Main problem with writing the formula in concentrations (e.g. [LA]) is that we actual mean Response in RU. But this is how most of the formulas are published.
Kind regards
Arnoud
        Last edit: 4 years 11 months ago  by Arnoud.            
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                5 years 1 week ago                #3
        by dirk
    
    
            
            
            
            
            
                                
    
                    
    
        Replied by dirk on topic Units in Mass Transfer k_t model            
    
        Thank you for your answer! Yes, that was exactly what confused me. Just using a factor of 10e9 RU/M would have been to simple because it doesn't take the molecule weight of the analyte into account.    
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