As the current COVID-19 pandemic has demonstrated, aerosolized pathogens such as SARS-CoV-2 can
spread explosively if not quickly detected. Early detection of these airborne pathogens can help control out-
breaks, particularly within vulnerable populations in densely populated spaces including assisted living facili-
ties, places of worship, military installations, hospitals, and prisons. To date, most studies of aerosolized
SARS-CoV-2 use filter collection followed by laboratory analysis of viral RNA. While this gives a general indica-
tion of viral RNA levels in an environment, filters collect both infectious and non-infectious viruses and damage
them through mechanical stress and desiccation, making it difficult to determine the infective fraction of the col-
lected viruses. Further, current filter analysis methods require time-consuming nucleic acid extraction and am-
plification techniques not suitable to rapid, point-of-care monitoring. Therefore, there is an urgent need for in-
struments that can detect intact viruses at the point-of-care.
We propose to develop a sensitive, direct reading, bioaerosol detection platform that can quantify specific air-
borne pathogens at the point of collection. Furthermore, if a positive result is identified, the sample can be
taken to a central laboratory for additional molecular analysis and infectivity testing. This device will integrate
the bioaerosol collection technology developed at Aerosol Devices Inc. (ADev) with virus detection technology
from Colorado State University (CSU). Using gentle condensation-growth capture that mimics the human lung,
the ADev sampler will be the front-end of the platform, concentrating intact, viable virus particles into a small
liquid volume. With >90% collection efficiency for particle sizes <10 nm up to 10 µm, ADev samplers uniformly
collect all inhalable SARS-CoV-2 particles whether originating from cough droplets (>5 µm), smaller particles
exhaled during breathing or talking (<5 µm), or shed as individual virus particles (~120 nm). CSU Professors
Henry, Dandy, and Geiss are developing innovative, inexpensive electrochemical biosensors to rapidly detect
intact viruses in liquid samples. By synergizing these robust sensors with the ADev aerosol sampler, we will
produce a system that can detect and quantify ultra-low concentrations of viral pathogens in near real-time.
In this phase I STTR project, we will adapt our commercial aerosol-into-liquid collector to incorporate CSU’s
biosensors. Specific aims for the ADev sampler include extending sampling time to 24 h to enhance limits of
detection, increasing volumetric sampling rate to improve temporal resolution, selecting materials compatible
with VHP decontamination and optimizing the system to reduce size, weight, power consumption and cost.
Specific aims for the biosensor include modifying electrodes to detect SARS-CoV-2 particles with high sensitiv-
ity and selectivity, adapting our current electrode configuration to work with the ADev sampling vial, and testing
the system with infectious SARS-CoV-2 in our BSL-3 laboratory. Our immediate focus is SARS-CoV-2, but this
technology can be adapted in Phase II to detect any airborne pathogen (e.g., Influenza, B. anthracis, etc.).