Chemical & Biological Dynamics

*****!!!!*** {Very useful info on chemistry. List of susceptible pathogens} "Chlorine dioxide exists in the water as ClO2 (little or no dissociation) and thus is able to permeate through bacterial cell membranes and destroy bacterial cells (Junli et. Al, 1977b). its action on viruses involves adsorbing onto and penetrating the protein coat of the viral capsid and reacting with the viral RNA... As a result, the genetic capability of the virus is damaged (Junli et. Al, 1977a). In comparison to chlorine, chlorine dioxide can be more effective as a disinfectant due to the fact that chlorine exists in the water as HOCL or OCL-. As a result, bacterial cell walls are negatively charged and repel these compounds, leading to less penetration and absorption of the disinfectant into the membranes. " "ClO2 DOES NOT REACT WITH: hippuric acid, cinnamic acid, betaine, creatine, alanine, phenylalanine, valine, leucine, asparaginic acid, asparagine, glutaminic acid...."

****!!!!*** 2020 label {Chart of some effective concentrations against pathogens}

This invention relates to biocidal blends comprising quaternary ammonium compounds and chlorine dioxide. It also relates to a process of inhibiting the growth of bacteria in aqueous system which comprises adding the biocidal blend to an aqueous system containing bacteria. The use of the biocidal blend results in an unexpected synergism.

"Surprisingly, chlorine dioxide was not effective for As III oxidation. A three-fold stoichiometric dose of chlorine dioxide produced only 20 to 30 percent oxidation in 21 seconds and none thereafter. Even a 100-times stoichiometric dose produced only 76 percent oxidation in five minutes."

{Note: Appropriate concentrations to use need to be verified) Disinfecting with sodium hypochlorite: "Based on the EPA List N: Disinfectants for Use Against SARS-CoV-2 products, 2500 ppm (0.25%) for 5 minutes is effective. Most readily available bleach is approximately 6% so 2/3 cup of bleach per gallon of cold tap water (1:24 dilution) for 5 minutes is appropriate." "If a lower concentration of bleach is desired, the EPA standard disinfection rate for hypochlorite products is 600 ppm for 10 minutes."

Free radicals and oxidants play a dual role as both toxic and beneficial compounds, since they can be either harmful or helpful to the body. They are produced either from normal cell metabolisms in situ or from external sources

"We evaluated the efficacies of formulated microbicidal actives against alpha- and beta-coronaviruses, including SARS-CoV-2. The coronaviruses SARS-CoV, SARS-CoV-2, human coronavirus 229E, murine hepatitis virus-1, or MERS-CoV were deposited on prototypic HITES or spiked into liquid matrices along with organic soil loads. Alcohol-, quaternary ammonium compound-, hydrochloric acid-, organic acid-, p-chloro-m-xylenol-, and sodium hypochlorite-based microbicidal formulations were evaluated per ASTM International and EN standard methodologies. All evaluated formulated microbicides inactivated SARS-CoV-2 and other coronaviruses in suspension or on prototypic HITES. Virucidal efficacies (≥ 3 to ≥ 6 log10 reduction) were displayed within 30 s to 5 min."

*****!!!!**** {Data on effectiveness of various disinfectants. Also data on survival of SARS-CoV-2 on various surfaces}

"virucidal effects of disinfectants by adding 15 μL of SARS-CoV-2 culture... to 135 μL of various disinfectants at working concentration ... With the exception of a 5-min incubation with hand soap, no infectious virus could be detected after a 5-min incubation at room temperature (22°C). Additionally, we also found that SARS-CoV-2 is extremely stable in a wide range of pH values at room temperature ... Overall, SARS-CoV-2 can be highly stable in a favourable environment,4 but it is also susceptible to standard disinfection method"

*****!!!!**** {This article only mentions chlorine dioxide effectiveness against SARS-CoV-1, not SARS-CoV-2, against which it has greater effectiveness} "The exposure of SARS-CoV-2 (7.8 of log10 (TCID50/ml) to 1:49 (~150 ppm) and 1:99 (~75 ppm) *household bleach* resulted in the virus titer being reduced below levels of detection after 5 min" "The aim of this review is to provide information, primarily to the food industry, regarding a range of biocides effective in eliminating or reducing the presence of coronaviruses from fomites, skin, oral/nasal mucosa, air, and food contact surfaces. As several EPA approved sanitizers against SARS-CoV-2 are commonly used by food processors, these compounds are primarily discussed as much of the industry already has them on site and is familiar with their application and use. Specifically, we focused on the effects of alcohols, povidone iodine, quaternary ammonium compounds, hydrogen peroxide, sodium hypochlorite (NaOCl), peroxyacetic acid (PAA), chlorine dioxide, ozone, ultraviolet light, metals, and plant-based antimicrobials. This review highlights the differences in the resistance or susceptibility of different strains of coronaviruses, or similar viruses, to these antimicrobial agents."

****!!!!**** {Direct testing against SARS-CoV-2} "To better inform the choice and use of disinfectants by DHS operators against SARS-CoV-2, the NBACC performed studies to evaluate the effectiveness of several products to reduce SARS-CoV-2 contamination when it was in simulated respiratory fluids. Disinfectants were tested against both wet and dried virus droplets to simulate disinfection of fresh and old contamination. No pre-cleaning or wiping was done during these tests to model a high tempo operations scenario where disinfectant is simply applied onto a potentially contaminated surface without precleaning or wiping"

****!!!!!*** {Chart of various disinfectants, hand sanitizers, etc directly against SARS-CoV-2}

{disinfectants tested against infectious bronchitis virus: IBV}

****!!!!!****!!!!*** {Includes chart of Chlorine Dioxide vs Sodium Hypochlorite effectiveness against many pathogens}

****!!!!*** Chlorine dioxide has been used for a disinfectant by exhibiting antimicrobial activity and is also potent to kill insect pests infesting stored grains. This study aimed to extend the usefulness of chlorine dioxide with respect to anticancer and antiviral activities. Cytotoxicity of chlorine dioxide was assessed against five different human cancer cell lines. Chlorine dioxide exhibited significant cytotoxicity against two breast cancer cell lines (MCF-7, MDA-MB-231) and three colorectal cancer cell lines (LoVo, HCT-116, SW-480). This cytotoxicity appeared to be associated with the capacity of chlorine dioxide to induce the production of reactive oxygen species (ROS). Compared to control insect cell lines, the cancer cell lines possessed much higher levels of ROS. On the other hand, a treatment of an antioxidant, vitamin E, significantly reduced the cytotoxicity, suggesting that the cytotoxicity was induced by high levels of ROS production. Chlorine dioxide exhibited antiviral activity against different viruses. A baculovirus, Autographa californica nuclear polyhedrosis virus (AcNPV), is a dsDNA insect virus and lost its viral activity to form polyhedral viral particles in response to chlorine dioxide. The antiviral activity against AcNPV was dependent on the incubation time with chlorine dioxide. Tobacco mosaic virus is a ssRNA plant virus and was reduced in its population after exposure to chlorine dioxide along with significant decrease of viral symptoms. These results indicate that chlorine dioxide possesses anticancer and antiviral activities probably due to its inducing activity of ROS production.

2013. "The quantitative sterilization test of the carrier showed that when the addition of gemini fluorocarbon, sodium xyl sulphate and sodium perfluoroyl peroxybenzene in disinfection liquid was 60, 60 and 40 mg/L, the concentration of chlorine dioxide disinfectant was 50mg/L, and the effect on Staphylococcus aureus on contaminated bacteria tablets was 10min, and the kill value was 3. When the amount of geminid fluorocarbon, sodium xyl sulfate and sodium perfluoroyl benzene phenyl sulfonate in disinfection liquid was 60mg/L, the concentration of chlorine dioxide disinfectant was 20mg/L, which acted on E. coli by 10min, and the kill-to-kill value was 3. The sterilization effect is better than that of using chlorine dioxide solution alone. On-site simulation tests showed that the concentration of chlorine dioxide in disinfection solution was 20mg/L, the concentration of sodium perfluorocarbonoxyl benzodiazepine was 40mg/L, and the disinfection liquid acted on E. coli on the surface of the object by 15min, and the kill pair was 3."

****!!!!****!!!!*** 2020. "reaction rate constants of ClO_2 with tryptophan residues in five heptapeptides and four proteins using stopped-flow or competition kinetic method.Each heptapeptide and protein contain only one tryptophan residue and the reactivity of tryptophan residue with ClO_2 was lower than that of free tryptophan (3.88×10~4 (mol/L)~(-1) sec~(-1) at pH 7.0).The neighboring amino acid residues affected the reaction rates through promoting inter-peptide aggregation,changing electron density,shifting pK_a values or inducing electron transfer via redox reactions.A single amino acid residue difference in oligopeptides can make the reaction rate constants differ by over 60%(e.g.3.01×10~4 (mol/L)~(-1) sec~(-1) for DDDWNDD and 1.85×10~4 (mol/L)~(-1) sec~(-1)for DDDWDDD at pH 7.0 (D:aspartic acid,W:tryptophan,N:asparagine)).The reaction rates of tryptophan-containing oligopeptides were also highly pH-dependent with higher reactivity for deprotonated tryptophan than the neutral specie.Tryptophan residues in proteins spanned a 4-fold range reactivity toward ClO_2 (i.e.0.84×10~4 (mol/L)~(-1) sec~(-1) for ribonuclease T1 and 3.21×10~4 (mol/L)~(-1) sec~(-1) for melittin at pH 7.0) with accessibility to the oxidant as the determinating factor.The local environment surrounding the tryptophan residue in proteins can also accelerate the reaction rates by increasing the electron density of the indole ring of tryptophan or inhibit the reaction rates by inducing electron transfer reactions."

"using modified maifanshi as the carrier and sodium chlorite and solid acid as the main agent, a new solid chlorine dioxide disinfectant that can release chlorine dioxide can be prepared by relying on environmental humidity, and the effect of the addition amount, activation temperature, various additives and environmental humidity on the release rate of chlorine dioxide was investigated. the results show that the addition of maifanshi can significantly reduce the peak of the release rate, eliminate the phenomenon of violent release, make the release rate in the later stage larger, and enhance the sterilization effect in the later stage; activation of maifanshi can enhance its adsorption capacity, and the optimal activation temperature is 100 °c; the addition of a certain amount of magnesium sulfate, calcium chloride and superabsorbent resin can make the release rate better controlled; the smaller the relative humidity, the more gentle the release of chlorine dioxide."

2019. "Using the method of drug-containing medium to study the effect of chlorine dioxide on the expansion of penicillin filament growth, it is found that chlorine dioxide can inhibit its growth, 400 mg L to (-1) chlorine dioxide can completely inhibit the growth of extended penicillin;" " By measuring the content of rod cytotoxin in apple fruit and liquid medium, it is found that chlorine dioxide can inhibit the content of lollipop toxin in apple fruit and liquid culture. 3. To expand penicillin as the target strain, to explore the effect of chlorine dioxide on the surface shape of its mycelium, cell membrane integrity, mitochondrial function, metabolic capacity and membrane peroxidation degree. Through scanning the electron mirror found that chlorine dioxide treatment can change the surface shape of extended penicillin filaments, make them rough, dry, after 350 mg L to (-1) chlorine dioxide after the expansion of penicillin silk surface found adhesion, serious collapse, the surface boundary of mycelium becomes blurred;" "chlorine dioxide can affect the expression of these 15 genes, suggesting that chlorine dioxide can reduce the yield of lollipop toxin by controlling the synthesis of rodtocin in penicillin."

2008

2015 "The danger of chlorine dioxide is mainly manifested in two aspects: the explosive properties of gaseous chlorine dioxide and its raw materials, and its adverse effects on food safety. Its explosiveness depends largely on the composition of their activators."

2015

"This paper analyzes the presence of ClO_2 and carbonate-presenter in the so-called "stable chlorine dioxide" solution prepared with stabilizer H_2O_2 and Na_2CO_3 and ClO_2, and compares the thermal stability, acid activation factors and sterilization effects of "stable chlorine dioxide" with pure NaClO_2 and ClO_2. The results showed that the ClO_2 in the solution of "stable chlorine dioxide" existed in chlorate ClO_2-type and carbonate in bicarbonate. It is also proved by theoretical analysis that the oxidation reduction and proton transfer reaction occurred between the ClO_2 and the H_2O_2 and the Na_2CO_3 during the preparation of the "stable chlorine dioxide" solution, which produced the chlorate ClO_2 -and bicarbonate HCO_3--- and released O_2. Therefore, the "stable dioxy-to-chlorine" solution is considered to be Cl"

1996

1998 "the results of the mutagenic comparison between chlorine dioxide and liquid chlorine disinfection water samples show that the water samples ClO_2 disinfection do not show mutation, while the wood samples of liquid chlorine disinfection show mutation"

2017. "In recent years, chlorine dioxide gas is directly dissolved in water, through the addition of stabilizers to become a direct use of products without activation, although the removal of the risk of insecurity, but also brought convenience to use, but the addition of stabilizers, reduce the purity of the solution, restricting the use of products in higher-end areas. The use of nanospheres directly to the absorption of chlorine dioxide gas, through control and then release, not only without any additives and activation, but also small size and large capacity, easy to use."

2012

2020. {Testing of various formulations on various organisms} "average concentration of chlorine dioxide in the high and low test groups was 224.1 mg/L and 75.2 mg/L, respectively. There was no significant difference between the average concentration of the high and low concentration groups and their theoretical concentrations, and the results of the chlorine dioxide content determinations were consistent with their theoretical concentrations. The average of the 5 measurement concentrations of the combined sodium chlorate powder dissolver in the control group was in the theoretical concentration (380 to 460 mg/L). Therefore, the improved five-step iodine measurement results are accurate, and the method can be used as an effective detection method for chlorine dioxide disinfectant products. The results of the qualitative quantitative killing test of chlorine dioxide solution on four bacteria showed that when the effective concentration of chlorine dioxide solution was 3.12 mg/L, it had a 1 min effect on E. coli 8099, and the kill rate was 99.90 %, 10 min for Staphylococcus aureus ATCC6538, the killing rate reached 99.97 percent, the effect on type B hemolytic streptococcus 32210 30 min, the killing rate reached 100%; The effective concentration was 12.5 mg/L, which was 10 min for bacillus 63501, and the kill rate was 100%. Chlorine dioxide solution sterilization effect is good, and with the compound sodium chlorate powder sterilization effect is similar, and the sterilization effect is much better than ammonium methyl bromide solution. The results of the killing test of chlorine dioxide solution on swine fever virus showed that chlorine dioxide solution and compound sodium chlorate powder dissolver with concentration of 25 mg/L were able to achieve 100% inactivation rate when the Thiveral strain of swine fever virus was 3 min, indicating that the chlorine dioxide solution had good effect on swine plague virus eradication and similar effect to the pig plague virus."