• Woottichai Khamduang, PhD Assistant Professor, Faculty of Associated Medical Sciences, Chiang Mai University

• Master student: Nyein Linn Maung

Airborne PM2.5 carries not only chemical pollutants but also biological materials, including bacteria, fungi, and viral nucleic acids. In Northern Thailand, seasonal biomass burning elevates PM2.5 levels significantly, yet information on associated airborne viruses remains limited. While metagenomic sequencing—particularly via Oxford Nanopore Technologies (ONT) with its real-time, long-read capabilities—enables broad microbial detection, viral analysis of PM2.5 is challenging due to the low concentration of viral nucleic acids amidst high background DNA. Therefore, this project aims to develop and evaluate an optimized ONT-based metagenomic workflow—encompassing extraction, amplification, sequencing, and bioinformatics—to improve the characterization of viral and microbial sequences from PM2.5 filters.

1) To develop a metagenomic workflow for recovering viral nucleic acids from PM2.5 filter samples using nucleic acid extraction, cDNA synthesis, amplification, library preparation and nanopore sequencing

2) To evaluate a preliminary SISPA-based workflow and an optimized workflow incorporating TURBO™ DNase treatment and SMART-9N cDNA synthesis

3) To establish a bioinformatic pipeline for sequencing quality control, primer trimming, quality filtering and taxonomic classification of ONT sequencing data

4) To characterize the relative abundance of viral, bacterial, and fungal taxa associated with PM2.5 filter samples

5) To evaluate the feasibility of the developed workflow as a methodological framework for future airborne virome research and environmental surveillance