I just got night contact lenses, and you are supposed to use a "one-step" cleaning solution to clean it over a period of six hours. At the bottom of the lenses case, there is a "titanium plate neutralizer", which causes the liquid to bubble. What is this gas?

Edit: it was platinum, not titanium


1 Answer 1


Hydrogen peroxide will damage your eye tissue; that's why there are enzymes in our cells actually to catalyze the conversion of $HOOH$ to water and oxygen gas. The enzymes are actually contained in peroxisomes (name is self-explanatory).* The neutralizer serves the same function of catalyzing the otherwise relatively slow decomposition of $HOOH$ into water and oxygen gas; hydrogen peroxide will decompose in the presence of light and that's why bottles of hydrogen perioxide are opaque - generally black or brown (but not transparent like bottles of which witch hazel or isopropyl alcohol). I have seen platinum used as a catalyst in contact cleaning solutions but I suppose titanium can be used as well.

*Edit: peroxisomes actually create $HOOH$ upon catabolism of cell by-products but can also break down its own toxic byproduct.

  • $\begingroup$ What happens to the platinum after it is used for a certain amount of time? The box says to replace the neutralizer disc after 30 days. Also, what happens to HOOH when it decomposes (what results)? $\endgroup$
    – Jason Chen
    May 10, 2014 at 21:49
  • $\begingroup$ You get water and oxygen gas when the HOOH dissolves. The platinum is actually consumed through HOOH decomposition. I've found out the hard way (from using my contact neutralization case for way over 30 days ... ouch!) $\endgroup$
    – Dissenter
    May 10, 2014 at 22:13
  • $\begingroup$ What does the platinum become after the chemical reaction? (just curious) $\endgroup$
    – Jason Chen
    May 10, 2014 at 23:14
  • $\begingroup$ So if after 30 days, I take out the neutralizer somehow and slice off the outer layer of platinum (which would be very hard indeed), would the reaction still work? $\endgroup$
    – Jason Chen
    May 11, 2014 at 3:52
  • $\begingroup$ I'm thinking there is a very, very thin layer of platinum on there so if you scrape off what was consumed, then you won't have much left. Also now I'm unclear on the catalysis of the decomposition of HOOH by Pt. By definition, a catalyst is NOT consumed in a reaction, but by all empirical means, it appears that Pt is consumed. Also, HOOH can be both reduced and oxidized, depending on pH. I'm thinking that HOOH is oxidized because that's when it creates oxygen gas. When it is reduced, it produces reactive radicals (not good for your cells!).If HOOH is oxidized then PT must be reduced; gains e- $\endgroup$
    – Dissenter
    May 11, 2014 at 3:55

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