The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is the virus responsible for the coronavirus disease 2019 (COVID-19) and was first detected in Wuhan, China, in December 2019. However, several studies have since confirmed that SARS-CoV-2 was circulating for months before COVID-19 cases were first reported in China; therefore, it is crucial to develop highly accurate sensors that can detect a wide range of viruses before they are able to spread uncontrollably around the world.
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What are Biohazard Sensors?
By definition, biosensors are analytical sensing devices capable of detecting the presence or concentration of biological analytes such as biomolecules or microorganisms. Typically, a biosensor will consist of three components: the physical sensor that recognizes the analyte and produces a signal, the signal transducer, and a reading device that interprets the signal.
Biohazards are a type of biological agent or chemical substance that can cause injury to humans, animals, and the environment; therefore, the development of biosensors capable of detecting these types of agents is of crucial importance.
For example, several biosensors have already been developed to detect biological warfare agents such as Bacillus anthracis, Francisella tularensis, Brucella sp., botulinum toxin, orthopoxviruses, and much more.
Although the use of biohazard sensors to detect these types of agents is often focused on mitigating military and terrorist efforts, they can also be used to identify circulating viruses to reduce transmission and the occurrence of global health crises like the current COVID-19 pandemic.
Biohazard Sensors for Virus Detection
Importantly, biosensors used to detect viruses are not considered alternatives or competitors to standard laboratory methods. Instead, these sensing devices can offer users an inexpensive and simple method for field analyses to either confirm standard laboratory results or screen potentially suspicious samples.
Optical biosensors are one type of analytical devices that have been used extensively for the detection of various biological agents such as Bacillus anthracis, staphylococcal enterotoxin, botulinum toxin, and orthopoxyviruses.
Many of these sensing devices are portable and based on colorimetric assays that allow
the detection of several biological agents on a single test strip.
Electrochemical sensors have also been widely used for the detection of biological agents as a result of their sensitivity to interfering compounds like metal ions and antioxidants.
The basic working principle of electrochemical agents can vary, some of which include antibody interactions, the recognition of specific DNA sequences, as well as the detection of metabolic or other forms of cellular activity. Some of the different biological agents that have been successfully detected with specialized electrochemical sensors include Bacillus cereus, Escherichia coli, Bacillus anthracis, botulinum toxin, and ricin.
Biohazard Sensors for Airport Security
Recently, a group of researchers at the Missouri University of Science and Technology have developed an airborne-biohazard system that can detect the presence of lung diseases caused by coronaviruses and other respiratory viruses in travelers. Their proposed system would require travelers to exhale into a sensor that would subsequently determine whether the traveler’s breath sample is positive or negative for a wide range of viruses.
In the event that a breath sample tests positive for a certain virus, it would be chemically tagged for further testing using a spectrometer.
In August 2021, the Teesside International Airport in England announced its use of the Kromek system, which is another type of sensing machine that would detect airborne COVID-19 particles.
To do this, the Kromek system collects samples from the surrounding air to identify the presence of viral particles that may be released from individuals who are not yet symptomatic for COVID-19.
The Kromek system sucks in 400 liters of air each minute and then condenses the biological materials into a single droplet of water. Within the system, Next Generation Sequencing (NGS) technology is used to read the genome of the acquired sample particles and compares these genetic sequences to a database of existing pathogen genomes.
One of the advantages of the Kromek system is that newly emerged pathogens, such as the constant mutation SARS-CoV-2 variants of concern, can be quickly incorporated into the system for early identification.
Taken together, various advancements have been made within the field of biosensors to improve the sensitivity of these devices for detecting a wide range of biological agents, including viruses and bacteria, that could significantly impact human health.
For several years, researchers and scientists worldwide have emphasized the ease to which a new virus could emerge and cause a similar impact to that which has been experienced as a result of the COVID-19 pandemic.
Therefore, it is essential to develop highly accurate and sensitive sensing devices that can quickly identify and isolate potentially dangerous viruses, particularly in airport travelers.
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References and Further Reading
Pohanka, M., 2019. Current Trends in the Biosensors for Biological Warfare Agents Assay. Materials, 12(14), p.2303. https://doi.org/10.3390/ma12142303
Chin, S. (2020) Airborne biohazard system screens travelers [Online]. Fierceelectronics. Available from: https://www.fierceelectronics.com/sensors/airborne-biohazard-system-screens-travelers.
Youd, F. (2021) Detecting airborne COVID-19: The machine that sniffs the air [Online]. Available from: https://www.airport-technology.com/features/detecting-airborne-covid-19-the-machine-that-sniffs-the-air/.