Antibacterial Testing

JIS L 1902/ISO 20743

Determination of Antibacterial Activity of Antibacterial Finished Products (Textiles)

This International Standard (ISO) specifies quantitative test methods to determine the antibacterial activity of antibacterial finished textile products, including nonwovens.

This International Standard (ISO) specifies quantitative test methods to determine the antibacterial activity of antibacterial finished textile products, including nonwovens.

It is appropriate for all textile products, such as cloth, wadding, thread and material for clothing, home furnishings and various goods independently of the type of antimicrobial agent used (organic or inorganic, natural or artificial) or the method of application (built-in, after-treatment or grafting). It depends on the projected application and on the environment where the textile product is intended to be used. Customers can choose an appropriate method for determination of antimicrobial activity: Absorption method: evaluation method, bacterial suspension is inoculated directly onto samples , The Colony Plate Count method and the Adenosine Triphosphate Luminescence method are also specified for quantifying the bacterial enumeration.

Organisms typically used in this method: Staphylococcus aureus (ATCC 6538P), Klebsiella pneumoniae (ATCC 4352) and Escherichia coli (ATCC 8739)

JIS Z 2801/ISO 22196

Measurement of Antibacterial Activity on Plastics Surfaces (Plastics)

This International Standard (ISO) specifies quantitative test methods to determine the antibacterial activity of antibacterial finished textile products, including nonwovens.

Standardized test organism is inoculated onto the surface of test material. The standard specifies an incubation period of 24 hours but other time periods can be accommodated. Surviving microorganisms are counted to evaluate the antimicrobial activity of the test material. Counts are determined before and after incubation. Using a formula provided in the standard, the log of the difference between the 2 counts is determined to give a measurement of antimicrobial activity.

Organisms typically used in this method: Staphylococcus aureus (ATCC 6538P), Klebsiella pneumoniae (ATCC 4352) and Escherichia coli (ATCC 8739)

AATCC-100

Antibacterial Finishes on Textile Materials: Assessment

This is a quantitative method for the determination of degree of antibacterial activity on textile materials.

Contact times are selected so that the test material would be effective in significantly reducing microbial counts during usage.

This test is performed with treated and non-treated samples of the test material. In accordance with AATCC 100 test procedure, 1 ml of test organism suspension at about 1000,000 CFU/ml is inoculated to the test sample.

At a given time, organisms are extracted with the help of a diluted and plated neutralizer medium.

This procedure tests both bacteriostatic activity (inhibition of multiplication) and bactericidal activity (killing of bacteria) of the antimicrobial test agent.
The hydrophobic characteristic of fabrics can affect the antimicrobial activity test results obtained by the AATCC 100 test method.

Organisms typically used in this method: Staphylococcus aureus (ATCC 6538P), Klebsiella pneumoniae (ATCC 4352) and Escherichia coli (ATCC 8739)

ASTM E2149

Standard Test Method for Determining the Antimicrobial Activity of Immobilized Antimicrobial Agents under Dynamic Contact Conditions

The test quantitatively evaluates the effectiveness of a sample treated with a non-leaching antimicrobial agent by shaking in an organism suspension.

This test method is designed to evaluate the resistance of specimens treated with a non-leaching antimicrobial agent to the growth of microbes under dynamic contact conditions. It has been developed for routine quality control and screening tests and is used to evaluate substrate bound antimicrobials. All the samples are shaken in dynamic shake flasks in a wrist action shaker to ensure good contact between the bacteria and the treated fibre, fabric, or other substrate by constant agitation of the test specimen in a bacterial suspension during the test period. Immobilized antimicrobial agents, such as surface bonded materials, are not free to diffuse into their environment under normal conditions of use. This test ensures good contact between bacteria and the treated fibre by constant agitation of the test specimen in a bacterial suspension during the test period (1hour). Microbial concentrations in the treated and untreated samples are usually determined at 0, 1 or 24 hours contact time.

Organisms typically used in this method: Staphylococcus aureus (ATCC 6538P), Klebsiella pneumoniae (ATCC 4352) and Escherichia coli (ATCC 8739)