Impact of human wound exudate on the bactericidal efficacy of antiseptic products in quantitative suspension according to the European standard (DIN EN 13727)

Abstract By default, antimicrobial efficacy of antiseptics used in wound management is tested in vitro under standardized conditions according to DIN EN 13727, with albumin and sheep erythrocytes used as organic challenge. However, it is not clear whether these testing conditions do adequately reflect the wound bed environment. Therefore, the aim of this study was to compare the efficacy of different antiseptic products based on octenidine dihydrochloride (OCT), polyhexamethylene biguanide (PHX), and povidone-iodine under challenge with human wound exudate instead of standardized organic load in an in vitro setting according to DIN EN 13727. Bactericidal efficacy of the tested products was reduced to different extend when challenged with human wound exudate compared to standardized conditions. Overall, OCT-based products showed the necessary germ count reductions at the shortest exposure times (e.g., 15 seconds for octenisept®). PHX-based products were the least efficient. In addition to the protein content, other components of wound exudates, such as the microflora, seem to influence the efficacy of antiseptics. This study demonstrates that standardized in vitro test conditions only partly reflect actual wound bed conditions. Consequences for an amendment of existing test methods adapting organic load requirements and the feasibility of standardization of wound exudates are to be discussed.

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Lack of Influence of Povidone-Iodine on Tests of Thyroid Function

Journal of International Medical Research ◽

10.1177/030006057800600510 ◽

1978 ◽

Vol 6 (5) ◽

pp. 406-408 ◽

Cited By ~ 4

Author(s):

D P Lividas ◽

G D Piperingos ◽

J Sfontouris ◽

D A Koutras

Keyword(s):

Thyroid Function ◽

Povidone Iodine ◽

Test Methods ◽

Thyroid Function Tests ◽

In Vitro Test ◽

External Application ◽

Vitro Test ◽

Antiseptic Agent

The external application of povidone-iodine, an antiseptic agent, was tested for its influence on thyroid function. Previous workers have described some in vitro changes in thyroid function tests following its use. In the present study topical application of povidone-iodine did not affect thyroid function as measured some days later using both in vivo and radio-active iodine in vitro test methods, despite the fact that the latter are notorious for being influenced by exogenous iodine.

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Animal Models and Alternatives in the Quality Control of Vaccines: Are In Vitro Methods or In Vivo Methods the Scientific Equivalent of the Emperor's New Clothes?

Alternatives to Laboratory Animals ◽

10.1177/026119299502300110 ◽

1995 ◽

Vol 23 (1) ◽

pp. 61-73

Author(s):

Coenraad Hendriksen ◽

Johan van der Gun

Keyword(s):

Quality Control ◽

Test Methods ◽

In Vitro Test ◽

Large Numbers ◽

Alternative Approach ◽

Inactivated Vaccines ◽

Vitro Test

In the quality control of vaccine batches, the potency testing of inactivated vaccines is one of the areas requiring very large numbers of animals, which usually suffer significant distress as a result of the experimental procedures employed. This article deals with the potency testing of diphtheria and tetanus toxoids, two vaccines which are used extensively throughout the world. The relevance of the potency test prescribed by the European Pharmacopoeia monographs is questioned. The validity of the potency test as a model for the human response, the ability of the test to be standardised, and the relevance of the test in relation to the quality of the product are discussed. It is concluded that the potency test has only limited predictive value for the antitoxin responses to be expected in recipients of these toxoids. An alternative approach for estimating the potency of toxoid batches is discussed, in which a distinction is made between estimation of the immunogenic potency of the first few batches obtained from a seed lot and monitoring the consistency of the quality of subsequent batches. The use of animals is limited to the first few batches. Monitoring the consistency of the quality of subsequent batches is based on in vitro test methods. Factors which hamper the introduction and acceptance of the alternative approach are considered. Finally, proposals are made for replacement, reduction and/or refinement (the Three Rs) in the use of animals in the routine potency testing of toxoids.

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