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Chlorine dioxide is a size-selective antimicrobial agent.

Noszticzius Z, Wittmann M, Kály-Kullai K, Beregvári Z, Kiss I, Rosivall L, Szegedi J - PLoS ONE (2013)

Bottom Line: ClO2, the so-called "ideal biocide", could also be applied as an antiseptic if it was understood why the solution killing microbes rapidly does not cause any harm to humans or to animals.Thus, a few minutes of contact time (limited by the volatility of ClO2) is quite enough to kill all bacteria, but short enough to keep ClO2 penetration into the living tissues of a greater organism safely below 0.1 mm, minimizing cytotoxic effects when applying it as an antiseptic.We hope initiating clinical applications of this promising local antiseptic.

View Article: PubMed Central - PubMed

Affiliation: Department of Physics, Budapest University of Technology and Economics, Budapest, Hungary.

ABSTRACT

Background / aims: ClO2, the so-called "ideal biocide", could also be applied as an antiseptic if it was understood why the solution killing microbes rapidly does not cause any harm to humans or to animals. Our aim was to find the source of that selectivity by studying its reaction-diffusion mechanism both theoretically and experimentally.

Methods: ClO2 permeation measurements through protein membranes were performed and the time delay of ClO2 transport due to reaction and diffusion was determined. To calculate ClO2 penetration depths and estimate bacterial killing times, approximate solutions of the reaction-diffusion equation were derived. In these calculations evaporation rates of ClO2 were also measured and taken into account.

Results: The rate law of the reaction-diffusion model predicts that the killing time is proportional to the square of the characteristic size (e.g. diameter) of a body, thus, small ones will be killed extremely fast. For example, the killing time for a bacterium is on the order of milliseconds in a 300 ppm ClO2 solution. Thus, a few minutes of contact time (limited by the volatility of ClO2) is quite enough to kill all bacteria, but short enough to keep ClO2 penetration into the living tissues of a greater organism safely below 0.1 mm, minimizing cytotoxic effects when applying it as an antiseptic. Additional properties of ClO2, advantageous for an antiseptic, are also discussed. Most importantly, that bacteria are not able to develop resistance against ClO2 as it reacts with biological thiols which play a vital role in all living organisms.

Conclusion: Selectivity of ClO2 between humans and bacteria is based not on their different biochemistry, but on their different size. We hope initiating clinical applications of this promising local antiseptic.

Show MeSH
Permeation of ClO2 through a gelatin membrane as a function of time t.Each point in the diagram represents a „black burst” (see Methods). V is the cumulative volume of the 0.01 M Na2S2O3 titrant added before the burst and N is the amount of ClO2 permeated until time t. TL1 = 627 s and TL2 = 175 s are time lags of the first and the second experiments, respectively. The concentration of ClO2 source in the magnetically stirred aqueous solution was 1360 ppm (mg/kg) or 20.1 mM.
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pone-0079157-g002: Permeation of ClO2 through a gelatin membrane as a function of time t.Each point in the diagram represents a „black burst” (see Methods). V is the cumulative volume of the 0.01 M Na2S2O3 titrant added before the burst and N is the amount of ClO2 permeated until time t. TL1 = 627 s and TL2 = 175 s are time lags of the first and the second experiments, respectively. The concentration of ClO2 source in the magnetically stirred aqueous solution was 1360 ppm (mg/kg) or 20.1 mM.

Mentions: Figure 2 shows the results of two consecutive experiments performed with the same gelatin membrane (see the two curves denoted as 1st exp. and 2nd exp.). After the first experiment, the membrane was removed from the apparatus and was kept in distilled water for 1 hour before the second experiment.


Chlorine dioxide is a size-selective antimicrobial agent.

Noszticzius Z, Wittmann M, Kály-Kullai K, Beregvári Z, Kiss I, Rosivall L, Szegedi J - PLoS ONE (2013)

Permeation of ClO2 through a gelatin membrane as a function of time t.Each point in the diagram represents a „black burst” (see Methods). V is the cumulative volume of the 0.01 M Na2S2O3 titrant added before the burst and N is the amount of ClO2 permeated until time t. TL1 = 627 s and TL2 = 175 s are time lags of the first and the second experiments, respectively. The concentration of ClO2 source in the magnetically stirred aqueous solution was 1360 ppm (mg/kg) or 20.1 mM.
© Copyright Policy
Related In: Results  -  Collection

Show All Figures
getmorefigures.php?uid=PMC3818415&req=5

pone-0079157-g002: Permeation of ClO2 through a gelatin membrane as a function of time t.Each point in the diagram represents a „black burst” (see Methods). V is the cumulative volume of the 0.01 M Na2S2O3 titrant added before the burst and N is the amount of ClO2 permeated until time t. TL1 = 627 s and TL2 = 175 s are time lags of the first and the second experiments, respectively. The concentration of ClO2 source in the magnetically stirred aqueous solution was 1360 ppm (mg/kg) or 20.1 mM.
Mentions: Figure 2 shows the results of two consecutive experiments performed with the same gelatin membrane (see the two curves denoted as 1st exp. and 2nd exp.). After the first experiment, the membrane was removed from the apparatus and was kept in distilled water for 1 hour before the second experiment.

Bottom Line: ClO2, the so-called "ideal biocide", could also be applied as an antiseptic if it was understood why the solution killing microbes rapidly does not cause any harm to humans or to animals.Thus, a few minutes of contact time (limited by the volatility of ClO2) is quite enough to kill all bacteria, but short enough to keep ClO2 penetration into the living tissues of a greater organism safely below 0.1 mm, minimizing cytotoxic effects when applying it as an antiseptic.We hope initiating clinical applications of this promising local antiseptic.

View Article: PubMed Central - PubMed

Affiliation: Department of Physics, Budapest University of Technology and Economics, Budapest, Hungary.

ABSTRACT

Background / aims: ClO2, the so-called "ideal biocide", could also be applied as an antiseptic if it was understood why the solution killing microbes rapidly does not cause any harm to humans or to animals. Our aim was to find the source of that selectivity by studying its reaction-diffusion mechanism both theoretically and experimentally.

Methods: ClO2 permeation measurements through protein membranes were performed and the time delay of ClO2 transport due to reaction and diffusion was determined. To calculate ClO2 penetration depths and estimate bacterial killing times, approximate solutions of the reaction-diffusion equation were derived. In these calculations evaporation rates of ClO2 were also measured and taken into account.

Results: The rate law of the reaction-diffusion model predicts that the killing time is proportional to the square of the characteristic size (e.g. diameter) of a body, thus, small ones will be killed extremely fast. For example, the killing time for a bacterium is on the order of milliseconds in a 300 ppm ClO2 solution. Thus, a few minutes of contact time (limited by the volatility of ClO2) is quite enough to kill all bacteria, but short enough to keep ClO2 penetration into the living tissues of a greater organism safely below 0.1 mm, minimizing cytotoxic effects when applying it as an antiseptic. Additional properties of ClO2, advantageous for an antiseptic, are also discussed. Most importantly, that bacteria are not able to develop resistance against ClO2 as it reacts with biological thiols which play a vital role in all living organisms.

Conclusion: Selectivity of ClO2 between humans and bacteria is based not on their different biochemistry, but on their different size. We hope initiating clinical applications of this promising local antiseptic.

Show MeSH