Sabouraud Dextrose Agar + LTHTh – ICR settle plates 90mm

Description

Ten lockable settle plates each with a diameter of 90 mm are triple-bagged in transparent, hydrogen peroxide impermeable sleeves. The product is gamma-irradiated in the final packaging at a dose of 9- 20 kGy. The sleeves consist of polypropylene with a barrier of PE-EVOH-PE.
The formulation of the basic medium (Sabouraud Dextrose Agar) is prepared according to the recommendations of the current European, Japanese and United States Pharmacopoeia (EP, 2.6.12.; JP, 4.05 and USP, 61) and supplemented with neutralizers.
Further plate designs are available with the same media formulation:
• SDA + LTHTh – ICR (article number 146005): 90 mm settle plates (pink dishes), triple-bagged, gamma-irradiated; intended for viable air monitoring (passive and active) and personnel testing in Clean rooms and isolators. The plate design allows aerobic incubation only.
• SDA cont. + LTHTh – ICR+ (article number 146501): 55 mm contact plates (pink dishes), triplebagged, gamma-irradiated; intended for microbial monitoring of air (passive and active) and personnel in Clean rooms and isolators. The “plus” plate design ensures a safe transportation.
• SDA cont. + LTHTh – ICR (article number 146201): 55 mm contact plates (pink dishes), triplebagged, gamma-irradiated; intended for microbial monitoring of air (passive and active) and personnel in Clean rooms and isolators. The plate design allows aerobic incubation only.

Mode of Action
Sabouraud Dextrose Agar (SDA) is a complex medium for cultivation and isolation of yeasts and molds. The medium is supplemented with pyruvate to provide an efficient neutralization of hydrogen peroxide for use in isolators. Furthermore, the medium is supplemented with the neutralizers’ lecithin, polysorbate (Tween®) 80, histidine and sodium thiosulfate. According to pharmacopoeia and ISO 18415, these neutralizers are suitable for neutralization of disinfectant residues containing the following active agents:
• Aldehydes
• Bis-biguanides
• Oxidizing compounds
• Parabens
• Phenolic compounds
• Quaternary ammonium compounds

The high concentration of Dextrose combined with the low pH promotes the growth, the formation of spores (conidia and sporangia) as well as the formation of pigments of yeasts and molds, whereas the growth of bacteria is inhibited.

Typical Composition

Casein Peptone 5 g/l

Meat Peptone 5 g/l

Dextrose 40 g/l

Polysorbate (Tween®) 80 5 ml/l

Lecithin 0.7 g/l

Histidine 0.5 g/l

Sodium thiosulfate 0.3 g/l

Agar 18 g/l

The appearance of the medium is clear and yellowish. The pH value is in the range of 5.4 to 5.8. The medium can be adjusted and/or supplemented according to the performance criteria required.

Application and Interpretation

The plates are introduced into Clean rooms grade A or B by removing one bag in each material lock. For use in isolators the inner bag has a hole in the sealing to hang up the bag during decontamination. Do not leave plates which are unprotected (unwrapped) in an isolator during decontamination.

Each plate is provided with a label including a data matrix code for paperless plate identification. The code consists of a two-dimensional 20-digit serial number, which harbors the following information: Digits 1-3: here code 722 (corresponds to article 146702); digits 4-9: lot number; digits 10-14: batch specific individual number; digits 15-20: expiry date (YY/MM/DD).

Please check each agar plate before using it on sterility and pay attention to aseptic handling to avoid false positive results. The plates may be used for passive or active air monitoring as described in USP chapter <1116> or ISO 14698. For active air sampling please follow the guidance of the air sampler. Typically, 1000 liter of air are sampled for quantification of CFU.

The exposure time of opened settle plates should be validated with respect to the environmental conditions of the sampling area such as flow rates, temperatures and relative humidity to preclude desiccation. Afterwards the plates are closed and transferred to an incubator. To protect the plates from secondary contamination during transport and incubation outside of the clean room zone, sterile transport bags (order number 146509) may be used. In addition, the plate model (plus or „+“) is supplied with a lockable lid.

For safe transport after sampling without the risk of losing the lid as well as for aerobic incubation the plates should be locked in the “CLOSED”-position (turn the lid clockwise). For anaerobic or microaerophilic incubation in the “VENT”- position (turn the lid counter-clockwise) is mandatory because this lid-position provides sufficient gas exchange with the atmosphere in the incubation chamber.

Aerobic incubation while turning the lid in “VENT”-position is also possible but may increase the desiccation of the agar plates during incubation. The “VENT” position is not required for detection of fungi. Several recommendations are given by different guidelines for incubation: according to USP <1116> the plates used for environmental monitoring should be incubated between 20 and 35 °C for not less than 72 hours.

According to the FDA Aseptic Guide the plates for determination of the total yeast and mold count should be incubated at 20 to 25 °C for 5 to 7 days. Individual incubation conditions can be chosen and should be validated at the application side.

Finally, the number of CFU per plate is examined. Grown colonies are recommended to be identified.

Storage and Shelf Life
The product can be used for sampling until the expiry date if stored upright, protected from light and properly sealed at +15 °C to +25 °C.
Condensation can be prevented by avoiding quick temperature shifts and mechanical stress. The testing procedures as described on the CoA can be started up to the expiry date printed on the label.

Disposal
Please mind the respective regulations for the disposal of used culture medium (e.g. autoclave for 20 min at 121 °C, disinfect, incinerate etc.).