Redesign and Development of a Biosampler and Evaluation of Its Collection Efficiency

Abstract

Introduction: Understanding the nature and concentration of airborne viruses such as SARS-CoV-2, influenza, and the common cold is essential for assessing transmission risk and developing preventive measures. This study aimed to evaluate the efficiency of BioSampler and impinger samplers in detecting these viruses in indoor air of healthcare centers in a southern city of Iran. In addition, the redesign and fabrication process of the BioSampler are presented.

Methods and Materials: The biosampler was redesigned based on scientific literature and manufactured at a laboratory equipment production center. Its collection efficiency was evaluated at different flow rates and varying volumes of absorbing liquid. Simultaneous air sampling was conducted using an impinger (2 L/min) and a BioSampler (15 L/min). A Munro L40 pump and a T-connector were used to operate both samplers concurrently. Sample analysis was performed using RT-PCR. In total, 20 air samples were collected from different hospital wards. Environmental parameters, including temperature, relative humidity, airflow rate, and air change rate, were measured.

Results: Airflow rates ranging from 5 to 20 L/min were evaluated. Collection efficiency reached its maximum at 15 L/min, and further increases in flow rate did not improve performance. The volume of collection liquid was examined from 10 to 25 mL, with the highest efficiency observed at 25 mL. No RNA of SARS-CoV-2, influenza, or common cold viruses was detected in any of the air samples.

Conclusion: No viruses were detected in samples collected using either the BioSampler or the impinger. This may be attributed to the effects of temperature and humidity on the viability of airborne viruses, the low concentration of virus-containing particles in the air, and potential limitations of the analytical method.