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TFC, 2ND, P. 194-, Alcamo 4th, pp 669-689, TFC 7^th, 193-205, 8^th: 192-204, Black 6^th: pp328-338, Bauman 2^nd: 276-281

Phenolics          injure plasma membrane, inactivate enz. halogenation increases effectiveness:

(p 276)              O-phenylphenol in Lysol

                           pHisoHex has hexachlorophene (led to neurological damage in infants)

ALCOHOLS   disrupts membranes and enzymes, therefore not effective against non-enveloped viruses or endospores. Especially good for surfaces, tho may primarily wipe off bacteria...

EtOH: 70% aqueous more effective, (water needed to denature protein) generally recommended

             Isopropanol seems more effective, less expensive.

             graph to compare effectiveness of 95% vs 70%

             tinctures: alcoholic solutions of antimicrobials

HALOGENS   may add to tyrosine, denaturing enzymes also strong oxidants,

                          usually used in tincture (EtOH soln) does not kill all viruses.

             Iodophors        bind the iodine to organic molecules, release slowly, non-irritationg, do not stain so badly: Betadine, Escodyne

             Chlorine           used on water esp. Ca hypochlorite (Ca(OCl)₂) used on dairy and swimming pools. Can produce carcinogenic chlorinated compounds.

                                       Chlorox is 5% NaOCl (1/2 tsp/2 gal clear water, 30 min, to disinfect.)

             Chloramines   Chlorine and ammonia, used to treat water in emerg., may not be carcionogenic

             Bromine           used in hot tubs, evaporates more slowly at elevated temperatures

OXIDIZING AGENTS

H₂0₂ better on inanimate surface (wound enzyme catalase inactivates)

             ozone (O₃)                     “Fresh smell” after electrical storm, can be used to sanitize water

             Zn peroxide:                  used to irrigate deep wounds,

             benzoyl peroxide           acne medicine (2 benzoates joined by oxygens)

SURFACTANTS emulsify oil on skin, allow removal of bacteria

             Quats:              quaternary ammonium salts: (p 279)

                                                    bacteriocidal against Gm +, mess up membranes, incr permeability

                                       Ceepryn, Zephiran, Phemerol. Pseudomonas can live on these...

HEAVY METALS combined with -SH groups, halt enzyme action (p 279)

             Ag        1% AgNO₃ commonly used, formerly for eye protection against gonorrhea

             Hg        in Mercurochrome and Merthiolate, will wash off, thimersal formerly in vaccines

             Cu        used against algae in reservoirs

             Zn        as anti bact & antifungal in mouthwash, paint, treatment for athletes foot

ALDEHYDES cross link proteins:  

             formaldehyde as formalin (37% aqueous soln), caution, carcinogenic

             glutaraldehyde (Cidex: 2% even kills spores in 3-10 hrs)

GASES      Ethylene oxide (EtO): alkylates proteins denaturing them. Toxic and explosive... (P 280)

                   highly penetrating, used to sterilize bedding etc. in hospitals

ORGANIC ACIDS inhibits mold by interfering with metabolism

benzoic acid, sorbic acid, propanoic acid (and salts of these: -ate)

activity not due to their acidity, rather to enzyme inhibition