Impact of Processing Method on Recovery of Bacteria from Wipes Used in Biological Surface Sampling

Abstract

<jats:title>ABSTRACT</jats:title><jats:p>Environmental sampling for microbiological contaminants is a key component of hygiene monitoring and risk characterization practices utilized across diverse fields of application. However, confidence in surface sampling results, both in the field and in controlled laboratory studies, has been undermined by large variation in sampling performance results. Sources of variation include controlled parameters, such as sampling materials and processing methods, which often differ among studies, as well as random and systematic errors; however, the relative contributions of these factors remain unclear. The objective of this study was to determine the relative impacts of sample processing methods, including extraction solution and physical dissociation method (vortexing and sonication), on recovery of Gram-positive (<jats:named-content content-type="genus-species">Bacillus cereus</jats:named-content>) and Gram-negative (<jats:named-content content-type="genus-species">Burkholderia thailandensis</jats:named-content>and<jats:named-content content-type="genus-species">Escherichia coli</jats:named-content>) bacteria from directly inoculated wipes. This work showed that target organism had the largest impact on extraction efficiency and recovery precision, as measured by traditional colony counts. The physical dissociation method (PDM) had negligible impact, while the effect of the extraction solution was organism dependent. Overall, however, extraction of organisms from wipes using phosphate-buffered saline with 0.04% Tween 80 (PBST) resulted in the highest mean recovery across all three organisms. The results from this study contribute to a better understanding of the factors that influence sampling performance, which is critical to the development of efficient and reliable sampling methodologies relevant to public health and biodefense.</jats:p>

Improved monitoring of P. aeruginosa on agar plates

“…3). 16,19,32 Another prospective use for this system is examining the antibiotic susceptibility of P. aeruginosa via the electrochemical detection of PYO (Fig. The electrochemical detection of PYO in this potential window also allows for the selective detection of P. aeruginosa from other clinically relevant pathogens (Fig.…”

Comparison of sampling methods to recover germinatedBacillus anthracisandBacillus thuringiensisendospores from surface coupons

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Beetroot-Pigment-Derived Colorimetric Sensor for Detection of Calcium Dipicolinate in Bacterial Spores

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