Acids in Human Biology

[3bromopyr]

Tumors are known to produce an extracellular environment which is acidic. How would acid/base concentrations be changed by this acidity?

For example, consider citrate circulating through the body. At physiological pH, this molecule dissociates to citric acid. However, what form would citrate take if exposed to the acidic pH of cancer (~6.5)? Are there chemicals that can shape shift from being neutral at a neutral pH to being acidic (or basic) in an acidic environment?  

 

 

[3bromopyr]

This is from the wiki article for citric acid. The curves represent  different species of citrate/citric acid at different pH levels. The species of citric(ate) present in the normal / cancer environment appears to fluctuate between A3- and AH2-.

Citrate is apparently the predominant species at physiological pH. ( Interested to know why.)

 

This gives a very explanation of protonation/depronation. Additional urls/details would be welcome.

http://ch302.cm.utexas.edu/chemEQ/polyprotics/polyprotics-all.php

Edited November 17, 2019 by 3bromopyr
Error

[3bromopyr]

My understanding of acids and bases is increasing, so I will explore further.

The molecule below is phenformin. Phenformin is described as being cationic at physiological pH. "Phenformin's dissociation constant (pKa) is 2.7, 11.8 (at 32 °C), ..." Where on the molecule will these disssociations occur?

 

 

 

Edited November 17, 2019 by 3bromopyr
Better spacing