WO2001034164A1

WO2001034164A1 - Disinfecting agent

Info

Publication number: WO2001034164A1
Application number: PCT/US1999/026351
Authority: WO
Inventors: Stephen Ray Wurzburger; James Michael Overton
Original assignee: Stephen Ray Wurzburger; James Michael Overton
Priority date: 1999-11-06
Filing date: 1999-11-06
Publication date: 2001-05-17
Also published as: AU1345500A

Abstract

A disinfectant is formed by selecting a metal hydride and an acid wherein the acid forms an insoluble salt with the metal, adding to a solution of the acid in gram equivalent amounts the metal hydride, and filtering the resultant solution to obtain a solution that is believed to consist essentially of oxonium ions but which, in its preferred embodiment, has less than 2500 parts per million of the metal salt and a pH of less than 2.5. In its preferred embodiment, the metal is calcium and the acid is sulfuric. The filter is preferably an eleven micron filter.

Description

DISINFECTING AGENT

TECHNICAL FIELD

This invention applies to relates to aqueous solutions for killing infectious microbes and particulai y to an aqueous solution having a large concenttation of oxonium ions that is a strong bactericide.

BACKGROUND

Many different substances can be classified as disinfectants. Chemical agents acting as disinfectants include strong acids and bases. The mode of action include one of five general types: oxidation, hydrolysis, modification of cell membrane permeability, mechanical disruption, chemical union.

A number of sulfur containing pharmaceutical compounds have been disclosed for use as bactericides.

For example, U.S. Patent 4,006,251 to Taylor et al discloses Thiocarbamylsulfenamide compounds.

U.S. Patent 5,084,449 discloses bis(4-aminophenyl-sulfonees. An apparatus (MicroWater™ distributed by Optimum Health Institute, San Mateo, Cal.) has been disclosed. The device produces two kinds of water with different redox potentials, one with a high reduction potential (referred to as "alkaline MicroWater") and one with a high oxidation potential (referred to as "acid MicroWater").

The acid Microwater has a been found to have commercially viable bactericidal properties when used in the lowest pH range (2.5) attainable (reported) for this solution. It is believed that the active molecule is the "hydronium"ion having the structure:

H+ H-O-H

It would be desirable to produce a solution of substantially exclusively oxonium ions having a pH less than 2.5 that would kill microbes on contact with the solution while not having a deleterious effect on human tissue since such a solution would be expected to have a stronger bactericidal effect than presently available solutions of oxonium ions.

The desire to express germicidal activity of various agents quantitatively has led to the development of numerous procedures, most of which are based on a phenol coefficient method developed by Rideal and Walker in 1906. The method involves culturing two batches of selected microbes for a period of time, one batch is disposed in a "standard" bactericide and the other batch is disposed in the "test" bactericide. A quantitative expression of effectiveness of the test bactericide may be expressed as a percent of the number of bacteria killed by test bactericide compared to the standard bactericide. Standard tests are outlined under ASTM guidelines.

DISCLOSURE OF INVENTION

In view of the above, it is an object of this invention to provide a stable micobicidal solution of substantially exclusively oxonium ions that is more effective than presently available solutions of oxonium ions having a pH of greater than 2.5.

It is an additional object that the solution be sufficiently stable for viable commercial purposes.

This invention is directed toward a method of making the solution which includes mixing a hydride of a metal with a molar equivalent of a strong acid wherein the metal and anion of the acid form an essentially insoluble salt that can be removed from the solution by filtration leaving an aqueous solution having concentration of Ca of not more than 2500 ppm and a concentration of sulfate ions of not mere than 2500 ppm and a pH less than 2.5.

In a preferred embodiment, the acid is sulfuric acid and the metal hydride is calcium hydride.

BRIEF DESCRIPTION OF THE FIGURES

Fig. 1 is a flow chart showing a method for making the invention. Fig. 2 is a flow chart showing fig. 1 in greater detail.

DESCRIPTION OF THE BEST MODE:

Turning now to a description of the drawings, fig. 1 is a flow diagram for one method of making the solution of this invention.

In step 1, a strong acid is selected together with the hydride of a metal wherein the metal and the anion of the acid forai a substantially insoluble salt.

In step 2 the acid is added to water forming an acid having an appropriate concentration.

In step 3 the metal hydride is added to the acid solution in a gram equivalent amount equal to the acid leading to the precipitation of the metal salt of the acid.

In step 4, the metal salt is filtered from the solution.

Fig. 2 shows the method in which the metal is calcium and the acid is sulfuric

In step 1, one mole of concentrated analytic grade of sulfuric acid is added to triple distilled water.

In step 2, slowly add 1 Gram Equivalent Weight of analytic grade CaH2 to the solution.

In step 3 slowly stir the solution until the reaction is complete producing a new solution.

In step 4 Pass the new solution through a 10 micron filter, removing all particles of CaSO4 larger than 10 microns.

In step 5, allow the solution to digest for 10 to 12 hours.

In step 6, filter the solution through an 11 micron filter.

To illustrate the invention by way of example, a sample of the invention was prepai'ed in accordance with fig. 2. Triply distilled water was used and the resultant test sample was found to contain less than 2500 ppm of sulfate and less than 2500 ppm of Calcium. The pH was 2.0. Bactericidal properties of the solution were evaluated by an independent laboratory, BioNir Laboratories, Inc. using the procedure ASTM El 153-87 which is hereby incorporated as reference into this specification. The method was modified in the following manner:

1. 22 mm² coverslips were used for the inocula step (step 3.2).

2. Only 0.6 mL of ARS-I was used on the coverslips.

3. Trypticase Soy Broth (TSB) pH 10 was employed as pH neutralizer.

4. 10 mL of TSB pH 10 with 0,6 mL of the test sample resulted in a final pH 6.7.

5. The test organisms were Staphylcoccous aureus and Enterobacter aerogenes.

6. Sterile petri dishes were substituted for sterile glass jars.

The results of the test are presented in table I.

Organism/Test Expected (cfu/m ιL) Observed Log reduction % reduction

S. aureus Control NA 50,000 NA NA

S. aureus A 50,000 <1 >4.5 99.995

S. aureus B 50,000 <1 >4,5 99.995

S. aureus C 50,000 90 2.7 99.9

E. aerogenes Ctrl NA 53,000 NA NA

E. aerogenes A 53,000 <1 >4.7 99.995

E. Aerogenes B 53,000 <1 >4.7 99.995

E. Aerogenes C 53,000 <1 >4.7 99.995

Conclusion of the testing lab (Bio-Nir): According to these test results, the test sample has demonstrated a capability of a 99.9 ->99.99% bactericidal effect within five minutes.

The pH of the test solution resulting from preparing the test solution in accordance with fig. 2 was measured to be 2.0 compared 2.7 which was the lowest value reported using the electrolysis method discussed in the BACKGROUND of the specification. The lower the attainable pH, it would be expected that the greater would be the bactericidal power of the product.

The reaction of the solution of this invention on human tissue has been tested many times in this laboratory at pH 2.0 and it has been found that there is no reaction whatsoever with periods of fifteen minutes exposure.

While WE DO NOT WISH TO BE BOUND BY THEORY, it is believed that the resultant solution consists essentially of hydronium ions in view of the purity of the water, (being less than 2500 ppm of either Ca or Sulfate) in spite of a pH of 2.0.

The solution prepared according to the techniques of this invention is apparently an oxidizing acid that can withdraw elections from bacteria and kill them. The solution contained in sufficient concentration (2.7 or lower) can be used to clean hands and utensils, meat, vegetables, fruit, and sterilize cutting boards and wounds. Tests have shown that

solutions of this type can be used effectively to treat athlete's foot t, bums, insect bites and wounds. It is excellent for cleansing and household use. It has bleaching ability. It disinfects and sterilizes yet is harmless to the skin. It is an astringent. It tightens skin.

A major advantage of the present invention over the prior art is the ease and economy of preparing the solution. The present method is a chemical method whereas the competing process is an electrophoretic method. The competing process has the major disadvantage that the equipment is relatively expensive and difficult to maintain due to such factors as fouling of filter membranes by metal ions that are initially in the water. Furthermore, the achievable pH of the electrolytic process (reported 2.7) is not as low as can be achieved with the present invention. Another major advantage is that the solution of the present invention maintains a pH of less than 2.5 for longer than 48 hours (actually months compared to the electrolytic process of the prior art where pH remains at 2.7 for only a few hours.

Variations and modifications of the invention may be suggested by reading the specification which are within the scope of the invention. For example, other metal hydrides may be considered along with acids forming insoluble metal salts with the metal.

These would include not only metals of the 2A group but also certain precious metals.'

These would include

Barium hydride and sulfuric acid;

Beryllium hydride and sulfuric acid. INDUSTRIAL APPLICABILITY

This invention provides a stable micobicidal solution of substantially exclusively hydronium ions that is more effective than presently available solutions of hydronium ions having a pH of greater than 2.5. Solutions of these ions are sufficiently stable for viable commercial purposes.

Claims

What is claimed is:

1. A method for preparing a solution having disinfectant properties which comprises the steps in operable order::

(a) selecting a metal hydride and an acid having an anion capable of forming an insoluble salt with said metal of said metal hydride;

(b) mixing a gram molar quantity of said acid in water;

(c) stining into said acid in water an equivalent of said gram molar quantity of said metal hydride;

(d) passing the resultant solution of step (c) through a filter to remove precipitates of salt formed by said metal and said acid.

2. The method of claim 1 wherein said step (a) includes the step: selecting said metal hydride to be calcium hydride and said acid to be sulfuric acid.

3. A solution consisting essentially of less than 2500 parts per million of calcium sulfate, and a pH of less than 2.5.

4. A solution consisting essentially of less than 2500 parts per million of calcium sulfate, sufficient oxonium ions to provide a pH of less than 2.5 wherein pH of less than 2.5 is maintained for longer than 48 hours..

5. A method for preparing a solution having a pH of less than 2.5, and less than 2500 parts per million of calcium sulfate which comprises the steps in operable combination of:

(a) forming a solution of one mole H2SO4 per one liter of water:

(b) stirring into said solution of step (a) one Gram Equivalent Weight of CaH2 per one mole of H2SO4

(c) filtering the solution of step (b) through an eleven micron filter;

(d) allowing the solution of step (c) to digest for at least 10 hours ;

(e) filtering the solution of step (d) through a two micron filter.

6. A method for treating an infected area of a human which includes the steps:

(a) forming a solution of one mole H2SO4 per one liter of water:

(b) stining into said solution of step (a) one Gram Equivalent Weight of CaH2 per one mole of H₂SO4

(c) filtering the solution of step (b) through an eleven micron filter;

(d) allowing the solution of step (c) to digest for at least 10 hours ;

(e) filtering the solution of step (d) through a two micron filter providing a disnfecting solution consisting of less than 2500 ppm Ca^{++ and} SO4 ^~ and a pH less than 2.5 that is stable longer than 48 hours;

(f) applying said disinfecting solution to said infected area