Antibacterial properties of cyclodextrin–antiseptics-complexes determined by microplate laser nephelometry and ATP bioluminescence assay

Abstract

Cyclodextrins (CDs) are able to form inclusion complexes with other molecules, thereby, protecting these guest molecules from degradation, enhancing their biocompatibility or influencing their physiological distribution while retaining their activity. Here, antibacterial effects of CD-complexes with the antiseptics chlorhexidine diacetate (CHX), iodine (IOD) and polihexanide (PHMB) were determined using two different in vitro methods, microplate laser nephelometry and an ATP bioluminescence assay. Laser nephelometry is a direct method for monitoring and evaluating growth of micro-organisms by measurement of the turbidity of the solution. In contrast, the ATP bioluminescence assay determines specifically the amount of metabolic active bacterial cells. The antibacterial effects of CD-antiseptics-complexes were examined for Escherichia coli, Klebsiella pneumoniae, Pseudomonas aeruginosa, Staphylococcus aureus and Staphylococcus epidermidis and the results of both methods were compared in respect of calculated means of half maximal inhibitory concentrations (IC50) and statistical evaluated Pearson's correlation coefficients (r). It could be demonstrated that both methods showed a high comparability although they differ in the parameters tested. This study revealed that CD-complexes with CHX and PHMB were most effective against E. coli and the tested staphylococci. While CD-IOD-complexes obtained high activity against K. pneumoniae, P. aeruginosa was distinctly more resistant compared to the other bacteria.

Mucoadhesive System Formed by Liquid Crystals for Buccal Administration of Poly(Hexamethylene Biguanide) Hydrochloride

“…Koburger et al (2010) compared the antiseptic efficacies of triclosan, octenidine, PHMB, PVP–iodine, and chlorhexidine digluconate and concluded that when a prolonged contact time is necessary or feasible (such as treatment of mucosal infections) PHMB presents the highest efficacy among the drugs studied. Considering that, there is an increasing interest in the development of novel drug delivery systems to vehicle PHMB as alternatives to improve the clinical effect of this drug to control microbial infections …”

“…Considering that, there is an increasing interest in the development of novel drug delivery systems to vehicle PHMB as alternatives to improve the clinical effect of this drug to control microbial infections. 11,12 The efficacy of antimicrobial agents in the treatment of oral infections is not solely related to in vitro antimicrobial activity. To be adequately effective, it is necessary to achieve a proper drug supply for an extended period.…”

Biocompatibility and Antibacterial Effects of 6-Deoxy-6-Aminoethyleneamino Cellulose

“…Strain maintenance was performed on Columbia agar plates with 5% sheep blood (Biomeriéux, France). Bacterial suspensions were prepared in CASO medium (Oxoid, UK) according to Finger et al [16]. …”

Bioluminescence assay for cell viability

“…Good agreement was obtained between the bioluminescence method and laser nephelometry when antibacterial prop erties of a series of cyclodextrin complexes were evaluat ed [36]. To assess the efficiency of new chemical disinfec tants, standard techniques developed by the European Committee for Standardization, EN 1276 and EN 13727 in particular, are used.…”