Chemical hydrogen peroxide indicator
The disclosed hydrogen peroxide indicator includes a substrate on which is disposed an indicator composition that includes at least one of a select group of indicator compounds and a catalyst. As a result of contact with hydrogen peroxide, the indicator composition changes color, even from colorless to having a visually observable color, thereby providing an indication of the presence of hydrogen peroxide.
1. An indicator article for detecting hydrogen peroxide, comprising
a substrate and an indicator composition deposited thereon, wherein the indicator composition comprises:
at least one indicator compound comprising 4,4′-diamino-2,2′-stilbenedisulfonic acid (DSSA); and
a catalyst comprising cerium (IV) oxide nanoparticles;
wherein the indicator composition comprises an optical property,
wherein a visually detectable change in the optical property of the indicator composition is associated with a presence of hydrogen peroxide.
2. The indicator article of claim 1 , wherein the cerium (IV) oxide nanoparticles are present in a range from 0.0001 wt. % to 20 wt. % of the indicator composition.
3. The indicator article of claim 1 , wherein the cerium (IV) oxide nanoparticles are present in a range from 0.005 wt. % to 1 wt. % of the indicator composition.
4. The indicator article of claim 1 , wherein the catalyst accelerates a color change of the indicator composition.
5. The indicator article of claim 1 , wherein the indicator compound is colorless by visual observation when dissolved in water at a concentration of up to 0.1 wt. %, prior to exposure to hydrogen peroxide vapor.
6. The indicator article of claim 1 , wherein the hydrogen peroxide is in a sterilant vapor.
7. The indicator article of claim 1 , wherein the change in the optical property of the indicator composition is a change from having no visually detectable color to having a visually detectable color.
8. The indicator article of claim 1 , wherein the indicator composition further comprises a polymeric binder and/or a crosslinker.
9. The indicator article of claim 1 , wherein the substrate is a polyester film.
10. A method comprising:
providing the indicator article of claim 1 , comprising the indicator composition;
exposing the indicator composition to hydrogen peroxide vapor;
and visually detecting a change in an optical property of the indicator composition upon exposure to the hydrogen peroxide vapor.
11. The method of claim 10 , wherein the change in the optical property of the indicator composition is a change from colorless to having a visually detectable color.