Antimicrobial membrane potential

An enormously important and diverse aspect of molecular recognition by synthetic ion channels and pores concerns specific interactions with the surrounding membrane. Only membrane potentials have been considered so far (Sections 11.3.4 and 11.3.6). The recognition of surface potentials by synthetic ion channels and pores has attracted much interest for the development of new antimicrobials [2]. 

Mirzoeva OK, Grishanin RN, Calder PC (1997) Antimicrobial action of propolis and some of its components the effects on growth, membrane potential and motility of bacteria. Microbiol Res 152 239-246... 

Little, R. G., II Abrahamson, S. Wong, P. Identiflcation of novel antimicrobial agents using membrane potential indicator dyes. PCX Int. Appl. WO 2000018951, 2000 Chem. Abstr. 2000, 132, 260670. 

All sulfonamides, including antimicrobial sulfas, diuretics, diazoxide, and the sulfonylurea hypoglycemic agents, have been considered to be partially cross-allergenic. Flowever, evidence for this is not extensive. The most common adverse effects are fever, skin rashes, exfoliative dermatitis, photosensitivity, urticaria, nausea, vomiting, diarrhea, and difficulties referable to the urinary tract (see below). Stevens-Johnson syndrome, although relatively uncommon (ie, < 1% of treatment courses), is a particularly serious and potentially fatal type of skin and mucous membrane eruption associated with sulfonamide use. Other unwanted effects include stomatitis, conjunctivitis, arthritis, hematopoietic disturbances (see below), hepatitis, and, rarely, polyarteritis nodosa and psychosis. 

Another kind of contact-active antimicrobial surface was achieved by tethering antimicrobial peptides to surfaces [62], If such peptides were exclusively membrane-active they could not work like in solution but would be immobilized via a polymeric spacer that could potentially cross the cell wall. The latter was demonstrated by the group of Dathe, who immobilized cationic antimicrobial peptides on PentaGels [63], Also, the well-known antimicrobial peptide magainin I... 

Octenidine is an antiseptic with proven antimicrobial qualities, which is frequently used as a disinfectant in surgery as well as antiseptic mouthwash with excellent tolerance especially when used on mucous membranes.23,24 It has even been shown to be effective in eradicating MRSA when used as an octenidine dihydrochloride whole-body wash combined with nasal mupirocin treatment.25 Due to the low irritant and allergic potential as well a low resistance rate, octenidine seems to be a substance with a promising future. 

In general, bioburden counts in parenteral solutions are obtained by conducting the total aerobic counts and total yeast and mold counts as specified in the USP microbial limits test (61) or an equivalent test [72], In addition, membrane filtration of larger than specified volumes may also be used to detect any microbial contamination when sample results are expected to contain a negligible number of microbial flora or in the presence of potential confounding factors, such as antimicrobial... 

Antimicrobial otic drops should be used with caution in the presence of a tympanic membrane perforation because of the potential for ototoxicity. In the case of suppuration, the ear canal should be cleaned before drop instillation. Purulence within the ear canal will not allow ototopical drops to penetrate the skin, and it is thus prevented from treating the ear infection. Ear cleaning is extremely important when suppuration occurs. 

A variety of otic preparations have been reviewed here, including indications, side effects, and limitations. The ideal cerumenolytic compound has not yet been developed, nor has a cerumen replacement product. Antiseptics enjoy wide application but are limited when used in the presence of a perforated tympanic membrane. Available antifungal medications appear to be adequate for the treatment of otomycosis, although none have been approved as otic preparations. The limitations of the otic antimicrobial drops have been stated, including the potential both for organism resistance and for ototoxicity. The recent introduction of Floxin and Cipro HC products make available better otic antimicrobial drops for treatment... 

Drugs able to affect outer-membrane integrity have also been exploited as potentiators of antimicrobial agents (biocides, i.e. disinfectants, antiseptics and preservatives, and antibiotics) thereby helping these to penetrate the outer membrane of Gramnegative organisms and especially Pseudomonas aeruginosa. 

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