CONTACT PLATE METHOD

Assessing Antibacterial Activity of Plastic and Fabric Samples with Non-Diffusible Antibacterial Agents

BioLabTests offers contact plate testing as a quick and simple test to determine the level of antibacterial efficacy in plastic and fabric samples. BioLabTests can accommodate contact plate testing using a variety of organisms relevant to your product’s application. If you are interested in this service, please get in touch.

The Contact Plate Method Procedure & Assessment

The test relies on a visual examination after a period of contact between your samples and bacteria. This test is applicable for antibacterial samples with non-diffusible antibacterial agents such as copper or silver. BioLabTests also offers AATCC 147 testing for diffusible antimicrobials in fabric samples.

Contact plate method: treated sample

Significant reduction of bacterial growth where the treated sample was in contact with the plate.

Contact plate method: untreated sample

Visible traces of bacterial growth where the untreated sample was in contact with the plate.

1. Preparation

A bacterial suspension of a chosen organism is diluted to an appropriate concentration.

2. Inoculation

Agar plates are inoculated with this suspension in 5 streaks across the plate.

3. Incubation

Samples are placed over the streaks and the plates are then incubated for 18-24 hours.

4. Assessment

After incubation, samples are assessed based on their ability to reduce bacterial growth where they were in contact with the bacterial streaks.

Things to note 

Recommendations

This method can give quick results before you proceed with more labour-intensive testing. BioLabTests recommends running this contact plate method before booking in any further antibacterial testing to confirm antibacterial efficacy.

Not what you are looking for?

Check out our comprehensive range of TEsting methods

ASTM E2149-13A

ASTM E2149-13A

  • Determining the antimicrobial efficacy of antimicrobial agents under dynamic contact conditions

  • Recommended for testing materials such as fabric, paper, powder and granular material

  • Evaluates the activity of an antimicrobial additive within non-leaching materials

ASTM G21-15

ASTM G21-15

  • Determining the effect of fungi on the properties of synthetic polymeric materials in the form of moulded and fabricated articles, tubes, rods, sheets, and film materials

  • Aspergillus brasiliensis is used as the predominant microbe in testing but it is possible to modify the method to suit a client’s specific needs