Comparisons of a Novel Air Sampling Filter Material, Wash Buffers and Extraction Methods in the Detection and Quantification of Influenza Virus

Abstract

300 words) 33 Quantification of aerosolized influenza virus is used for determining inhalation exposure. Several 34 bioaerosol samplers and analytical methods have been used; however, the detection and 35 quantification of influenza virus among aerosol samples remains challenging. Therefore, 36 improved viral aerosol measurement methods are needed. This study evaluated influenza virus 37 recovery among three filter types polytetrafluoroethylene, polyvinylchloride and polystyrene. 38 Polytetrafluoroethylene, polyvinylchloride are fabricated filter materials and commonly used in 39 the scientific literature to sample for viral aerosols. A novel, electrospun polystyrene filter 40 material may improve viral aerosol recovery during filter-based air sampling. The filter materials 41 were compared across the following conditions: treated with or without air, filter wash buffer 42 (HBSS or PBS), and viral RNA extraction method (QIAamp Viral RNA Mini Kit or Trizol). 43 Twenty trials were completed in a chamber and samples were analyzed using RT-qPCR. Viral 44 recovery was significantly different (p-value < .0001) by filter type. Polystyrene filter use 45 resulted in recovery of the most viral RNA. Air sampling did not affect the recovery of viral 46 RNA from the filter materials (p-values > 0.05). Viral RNA concentrations were significantly 47 different across extraction methods for all comparisons (p-values < 0.05). Our results 48 demonstrated that the novel polystyrene filter material resulted in the highest concentration of 49 extracted RNA compared to the commonly used polytetrafluoroethylene and polyvinylchloride, 50 which we speculate may be related to the chemical composition of the filter material (e.g., 51 polystyrene is an aromatic hydrocarbon whereas polytetrafluoroethylene and polyvinylchloride 52 contain more polar, and thus potentially reactive, carbon-halogen bonds). Air sampling did not 53 have an effect on viral RNA recovery. Using Hanks Balanced Salt Solution with QIAamp Viral . CC-BY 4.0 International license is made available under a The copyright holder for this preprint (which was not peer-reviewed) is the author/funder. It . https://doi.org/10.1101/441154 doi: bioRxiv preprint 54 RNA Mini Kit, and Phosphate-buffered saline with the Trizol extraction, resulted in the most 55 viral RNA recovery. 56 57 58

Particulate matter (PM2.5) as a potential SARS-CoV-2 carrier

“…Prior to viral nucleic acid extraction, the membrane filter was processed according to 35 with slight modifications. The membrane was first divided into four parts and immersed in 1 mL sterile RNase-free water in separate tubes.…”

Comparison and improvement of RNA extraction methods in Sargassum (Phaeophyta)

“…The success of eukaryotic RNA extraction depends heavily on adequate lysis, elution, and purification, which need to be taken into account when modifying the methods (Chun et al, 2008; Lázaro‐Perona et al, 2021; Thedell et al, 2018). In this study, we successfully isolated high‐yield and high‐quality RNA from Sargassum species using four modified methods.…”

Early Warning Diagnostics for Emerging Infectious Diseases in Developing into Late-Stage Pandemics

“…Suspension media composed of PBS, HBSS, or DI water mixed with aid serum have been widely used in pathogenic studies. 47 The inactivation of pathogens, high impact forces, airflow, and the electric potential can impair the structure of the pathogen further, complicating downstream quantification and analysis of the viruses and thus their estimated threat at the initial time and place of collection. 48 While a vast number of studies demonstrate that viral detection is achieved through extraction protocols followed by RT-PCR, determining infectious vs noninfectious pathogens is much more challenging and time-consuming, especially for viruses.…”

“…From these media, gelatin-based filters are soluble, removing the removal step and reducing inactivation. Suspension media composed of PBS, HBSS, or DI water mixed with aid serum have been widely used in pathogenic studies . The inactivation of pathogens, high impact forces, airflow, and the electric potential can impair the structure of the pathogen further, complicating downstream quantification and analysis of the viruses and thus their estimated threat at the initial time and place of collection …”