Talk:MiPNet19.03 O2k-cleaning and ISS

Cleaning with diluted acids

Question: Colleagues and I want to introduce heavy metals into the chambers of the oxygraph-2k. We were wondering what that would mean in terms of cleaning: Would acid-washing the chambers with either 0,1-0,3N HNO3 or HCl be a problem for the membranes?

Answer: The glass chambers and membranes (FEP) would not be a problem, but some polymeric components might. Therefore, we tested approx 0.3 M HNO3 over night at room temperature plus 2 hours at approx 35 °C on the following materials: FEP (POS membranes), PVDF ( white stoppers), POM O2k-Chamber Holder), butyl rubber ( OroboPOS-Seal Tip, and Viton O-ring\Viton\12x1 mm. No immediately visible problem was detected. Frequent or prolonged use might of course still have negative effects. Since HNO3 was nor problem for the polymers (non oxidizing) HCl of similar concentration is presumable save.

Of course 0.3 M HNO2 is still a rather mild way to deal with heavy metal contaminations. Classical methods (cocentrated acids) would require to remove the glass chamber and clean it outside the O2k as described for protein contamination MiPNet19.03_O2k-cleaning_and_ISS#General_cleaning_instructions. Fasching Mario 15:45, 20 August 2014 (CEST)