Analysis of Four-Hours Active Sampling Using 90 mm Plates + LTHT

Ludovica Borghesi; Marco Redaelli; Giovanni Abramo

Acta Scientific Medical Sciences (ASMS)(ISSN: 2582-0931)

Research Article Volume 9 Issue 11

Analysis of Four-Hours Active Sampling Using 90 mm Plates + LTHT

Ludovica Borghesi¹, Marco Redaelli¹ and Giovanni Abramo²*

¹Microbiological Laboratory Technician, DMX Pharma, Italy
²Head of Microbiological Laboratory, DMX Pharma, Italy

*Corresponding Author: Giovanni Abramo, Head of Microbiological Laboratory, DMX Pharma, Italy.

Received: August 28, 2025; Published: October 14, 2025

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Abstract

3) through a perforated lid. This study focuses on continuous active air sampling using 90 mm plates and Active Air Sampler (AAS) devices, in accordance with ISO 14698:1-2003. The aim of this study was to increase the sampling time from 2 to 4 hours and the air volume from 1 m³ to 2 m³. At the end of the aspiration process plates was examined morphologically, to assess potential dehydration, and microbiologically for growth promotion capability. The results obtained after 4 hours of operation and 2 m³ of sampled air showed no signs of dehydration, as no reduction in agar thickness was observed.

Furthermore, there was no impairment of the microbial growth or recovery properties. Therefore, the morphological integrity and nutritional characteristics of the plates remained unchanged, which was crucial for understating the impact of active sampling on the plates and for ensuring the reliability of microbiological data obtained during environmental monitoring.

In conclusion, the study met the acceptance criteria required for environmental monitoring, including: i) microbial growth compliant with incubation conditions on all plates; ii) recovery of microorganisms ranging between 50% and 200%; iii) absence of dehydration phenomena.

Keywords: Environmental Monitoring; Active Air Sampling; Dehydration Phenomena; Growth Promotion; Recovery

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Citation

Citation: Giovanni Abramo., et al. “Analysis of Four-Hours Active Sampling Using 90 mm Plates + LTHT”.Acta Scientific Medical Sciences 9.11 (2025): 12-20.

Copyright

Copyright: © 2025 Giovanni Abramo., et al. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.