Oxoid updates contact plate design

Oxoid has introduced a new plate design for the Oxoid range of Contact Plates, which aims to make the microbiological testing of surfaces even easier to store, handle and use.

Widely used within the pharmaceutical industry, contact plates are typically used for environmental monitoring within clean room facilities as well as forming a crucial part of drug research and development.

The new design makes the plates much easier to manipulate and, to maximise storage space, they are now more stable when stacked together.

In addition, the new grip-lock lid helps to prevent accidental exposure of the agar ensuring the integrity of the medium during handling and transport.

Monitoring the microbial flora of environmental surfaces, manufacturing plants, and equipment is an important stage in achieving Good Manufacturing Practices (GMP) in facilities handling pharmaceuticals and medical devices.

Pharmaceutical and medical device manufacturing facilities have stringent sterility requirements for surface sampling in cleanrooms and isolators.

Oxoid Contact Plates are manufactured using a specialised automated procedure to ensure a smooth, evenly distributed layer of agar on each plate.

Surface sampling is achieved by gently rolling the domed surface of the agar onto the area to be tested. A grid on the base of the plate subdivides the growth area for accurate, semi-quantitative colony counts.

The contact plate method is recommended when quantitative data are sought from flat, impervious surfaces. Contact plates are filled so that the media forms a dome. The nutrient medium used in the contact plate may also contain a neutralizing agent. The surface of the media is pressed against the surface being tested.

Disadvantages of the contact plate method are that this method is not suitable for sampling of irregular surfaces, confluent growth of microorganisms can occur, and the media residue must be removed from the sampling site.

The Oxoid Contact Plate range includes high quality culture media for total aerobic microbial counts, coliform bacteria counts and yeast/mould counts. Tailor-made plates are also available on request for specialist applications.

The plates are irradiated and triple-wrapped, making them ideal for use in designated clean areas.