Team:Brown-Stanford/Lab/Protocols/Conductivity
From 2011.igem.org
Conductivity Measurements of Ureolysis
(Guided by conductivity protocol of [[http://researchrepository.murdoch.edu.au/399/2/02Whole.pdf Whiffen et al. (2004)]])
Reagents/supplies
- Cell culture(s), 5 mL per culture of known cell density
- 1.5M Urea, 30 mL per culture
- Conductivity meter
Protocol
- Before beginning, equalize the temperatures of both the 1.5M urea solution and the liquid cultures are made constant; changes in temperature can have large effects on the conductivity of ionic solutions, and a change in temperature may overshadow the increase in conductivity due to ureolysis
- Calibrate conductivity meter
- Take background measurements of the conductivity of both staring solutions
- Add 30 µL of 1.5M urea to each cell culture. Measure conductivity at prescribed intervals
Calculations
- Urea hydrolyzed (mM) = Conductivity (mS/cm) x 11.11 at 25˚C