Biocides cationic

Kugler R, Bouloussa O, Rondelez F (2005) Evidence of a charge-density threshold for optimum efficiency of biocidal cationic surfaces. Microbiology 151 1341-1348... 

Campanac, C., Pineau, L., Payard, A., Baziard-Mouysset, G. and Roques, C., 2002. Interactions between biocide cationic agents and bacterial biofilms. Antimicrobial Agents and Chemotherapy 46, 1469-1474. 

A strong adsorption of the major part of a biocide on the soil clay minerals reduces its bioavailability and must be compensated by addition of increased amounts. On the other hand, dangerous biocide cations adsorbed on the clay minerals constitute a long-term health hazard when slowly released to the ground water. Coadsorption of the pesticide together with a non-phjrtotoxic compound or displacement of the pesticide (for instance diquat by 4-pyridyl pyridinium chloride [32]) reduce this threat and increase the bioavailability. As shown by Narine and Guy [20], the divalent cations paraquat and diquat are more easily displaced by washing with salt solutions than monovalent cations such as methylene blue and thionine. 

Many benzenoid quaternary cationic surfactants possess germicidal, fungicidal, or algicidal activity. Solutions of such compounds, alone or in combination with nonionic surfactants, are used as detergent sanitizers in hospital maintenance. Classified as biocidal products, their labeling is regulated by the U.S. EPA. The 1993 U.S. shipments of cationic surfactants represented 16% of the total sales value of surfactant production. Some of this production is used for the preparation of more highly substituted derivatives (101). 

Azaadamantanes biocide, 1, 400 mechanism, 1, 401 photoelectron spectroscopy, 2, 142 5-Azaadenines reactions, 5, 878 synthesis, 5, 901 8-Azaadenosines synthesis, 5, 895 Azaallyl cations generation, 7, 73 Aza[10]annulenes bridged... 

Mechanisms (1) Alteration of biocide (enzymatic inactivation) (2) Impaired uptake (3) Efflux Chromosomally mediated, but not usually relevant Applies to several biocides Not known Plasmid/Tn-mediated e.g. mercurials Less important Cationic biocides and antibiotic-resistant staphylococci... 

Members of the genus Proteus are unusually resistant to high concentrations of ehlorhexidine and other cationic biocides and are more resistant to EDTA than most other types of Gram-negative bacteria. A less acidic type of LPS may be responsible... 

The clinical relevance of biocide resistance of antibiotic-resistant staphylococci is, however, unclear. It has been claimed that the resistance of these organisms to cationic-type biocides confers a selective advantage, i.e. survival, when such disinfectants are employed clinically. However, the in-use concentrations are several times higher than those to which the organisms are resistant. 

One will loose biocidal activity due to the presence of iron and manganese in the pool water because chlorine and chlorine related products will oxidize these cations ... 

Lead is toxic to all phyla of aquatic biota, but its toxic action is modified by species and physiological state, and by physical and chemical variables. Wong et al. (1978) stated that only soluble waterborne lead is toxic to aquatic biota, and that free cationic forms are more toxic than complexed forms. The biocidal properties of soluble lead are also modified significantly by water hardness as hardness increases, lead becomes less bioavailable because of precipitation increases (NRCC 1973). In salmonids, for example, the toxicity and fate of lead are influenced by the calcium status of the organism, and this relationship may account for the reduced effects of lead in hard or estuarine waters. In coho salmon (Oncorhynchus kisutch), an increase in waterborne or dietary calcium reduced uptake and retention of lead in skin and skeleton (Varanasi and Gmur 1978). 

Complex cyanides are compounds in which the cyanide anion is incorporated into a complex or complexes. These compounds are different in chemical and toxicologic properties from simple cyanides. In solution, the stability of the cyanide complex varies with the type of cation and the complex that it forms. Some of these are dissociable in weak acids to give free cyanide and a cation, while other complexes require much stronger acidic conditions for dissociation. The least-stable complex metallocyanides include Zn(CN)42 , Cd(CN)3 , and Cd(CN)42 moderately stable complexes include Cu(CN)2, Cu(CN)32, Ni(CN)42, and Ag(CN)2 and the most stable complexes include Fe(CN)64, and Co(CN)6. The toxicity of complex cyanides is usually related to their ability to release cyanide ions in solution, which then enter into an equilibrium with HCN relatively small fluctuations in pH significantly affect their biocidal properties. 

Many ionic liquids have been widely investigated with regard to applications other than as liquid solvents such as electrolytes, phase-transfer reagents, surfactants, and fungicides and biocides. The physical and chemical properties of ionic liquids can be varied over a wide range by the selection of suitable cations and anions. Some of the properties that depend on the cation and anion selection includes melting point, viscosity, density, acidity and coordination ability, solvation strength and solubility characteristics. ... 

These cationic surfactants appear to act by breaking crosslinks between polypeptide chains. Unlike the majority of biocides, they do not have to penetrate into the cell instead they disrupt the structure of the semipermeable membrane allowing leakage of cell constituents (B-60MI11500). 

MA/EA/VA provides good corrosion control in both soft and hard waters in combination with zinc. It is polyanionic and therefore, as with all anionics, care should be exercised with certain cationic biocides. It is resistant to chlorine degradation. 

These products tend to have the highest degree of surfactant action. The cationic nature permits neutralization of the typically anodic biofilm. Cationics should not be used with anionic biocides, such as chlorophenols. Formulations tend to be based on a blend of BCP, quat, or polyquat and silicone defoamer. 

It is sometimes desirable to have surfactants that can act as biocides as well, especially in cleaning and sanitizing applications. Some cationic surfactants are toxic to bacteria, fungi, and algae. The most common biocidal surfactants have quaternary ammonium polar groups, ranging from quaternary amines to amine oxides. 

Kanazawa A, Ikeda T, Endo T (1993) Polymeric phosphonium salts as a novel class of cationic biocides. III. Immobilization of phosphonium salts by surface photografting and antibacterial activity of the surface-treated polymer films. J Poly Sci A Poly Chem 31 1467-1472... 

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