Shelf-Life Assessment of Agar Plates Vacuum-Sealed in Nylon/Polyethylene Packaging Flushed with Nitrogen

Abstract

In resource-limited nations, enhancing the shelf-life and stability of critical reagents and consumables is desired. This study evaluated the shelf-life of bacteriological plates in vacuum-sealed nylon/polyethylene packaging flushed with nitrogen (FlatPacks®). Tryptic soy agar (TSA) FlatPacks held at room temperature for 24 months did not change in appearance or texture and supported bacterial growth similar to Day 0 concentrations. In contrast, TSA plates from a different supplier (Vendor A) desiccated after 4 months of storage at room temperature. TSA, blood agar (BA), and chocolate agar (CA) FlatPacks subjected to desert-like storage and transport temperatures (60 °C) for 30 days supported bacterial growth similar to FlatPacks held at room temperature or refrigerated; TSA, BA, and CA plates (Vendor A) desiccated within 7 days. The data suggest FlatPacks extend the shelf-life of TSA stored at room temperature when compared to traditional packaging. Additionally, TSA, BA, and CA FlatPacks support bacterial growth for at least 30 days when stored at 60 °C. Based on the results of this study, the FlatPacks may help laboratories in resource-limited nations overcome infrastructure, refrigeration, and supply-chain deficiencies.

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Digital dipstick: miniaturized bacteria detection and digital quantification for the point-of-care

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