Standard Practice for Preparation Of Cell Monolayers on Glass Surfaces for Evaluation of Microbicidal Properties of Non-Chemical Based Antimicrobial Treatment Technologies

Importancia y uso:

5.1 There are no reproducible standardized protocols for preparing specimens used to evaluate the microbicidal efficacy of non-chemical treatments such as ultraviolet (UV), highenergy electron beam, or other forms of non-chemical antimicrobial technologies.

5.2 Conventional protocols for applying bioburdens to carriers (see Test Method E2197) cause cells to stack upon one another, thereby creating multiple cell layers in which cells in layers closer to the carrier are masked by cells in overlying layers, which makes relative comparison of different non-chemical antimicrobial treatments more difficult.

5.3 Steel and other metal carriers have asperities that can shield a percentage of the applied cells from direct exposure to electromagnetic irradiation.

5.4 The combined effects of 5.2 and 5.3 confound determination of the microbicidal effect of electromagnetic irradiation on test specimens.

5.5 The practice addresses these two confounding factors by:

5.5.1 Using glass microscope slides – the surfaces of which are asperity-free – as carriers.

5.5.2 Reliably depositing bacterial cells onto the carrier as a monolayer.

5.6 The resulting specimen ensures that all microbes deposited onto the carrier are exposed equally to the irradiation source thereby ensuring that the only variables are the controlled ones – starting inoculum concentration, wavelength (λ – in nm), exposure time(s), and resulting energy dose (J).

Subcomité:

E35.15

Referida por:

E2756-24A

Volúmen:

11.08

Número ICS:

07.100.01 (Microbiology in general)

Palabras clave:

automated inoculum deposition; bacterial inoculum; bacterial monolayer; disinfection standard; disinfectant agent testing; EPA SOP; FMUV; healthcare; light-based disinfectant; MB-06-09; monolayer; non-chemical disinfectant; ultraviolet disinfection; ultraviolet light; UVC;