PH changes, measurement

As far as ApH measurements have been taken as a basis [9], overestimation of ApH has been arisen from the use of a false fluorescence quenching interpretation. (3) Direct H flux measurements during ATP synthesis [10] may have suffered from a limited response time of the experimental setup for pH change measurement. 

For the pH change measurements, the bacterial cells was washed with 300 mM KCl. pH changes were measured with a pH electrode. The cell suspension was kept anaerobic for 30 min befor the measurement. 

---