Scientists from Russian state science and research institute of biological instrumentation developed a device, which measures real-time concentration of biological aerosols in air. This device promises to be helpful in case of huge technogenic accidents or (God forfend!) terrorist attacks.

It has always been very difficult to detect presence of dispersed bacterial cells or viruses in the air. Nowadays atmosphere’s health is usually monitored and protected by common means of microbiological analysis. However, mentioned standard techniques are quite time-consuming, thus not suitable for real-time monitoring of atmospheric state. Modern equipment, developed for controlling biological environment, cannot boast high sensitivity; moreover, it becomes even less sensitive, when air happens to contain particles of dust. All these devices cannot provide real-time measurements of bacterial cells’ concentration.

 

 

Well, there really is light at the end of the tunnel. Russian engineers developed a device, which lacks all abovementioned drawbacks. Said “panacea” works the following way: the unit registers spectral characteristics of light, which is emitted or dispersed by biological particles. Biological aerosols always contain some aromatic compounds, which show specific absorbance parameters in ultraviolet range of light spectrum and dissipate light in both ultraviolet and visible light ranges. Intensity of light dissipation, when it comes from an aerosol particle, varies and depends on several factors. Among most important ones we should mention size of biological particles and their absorbance coefficient on a certain wavelength. Said characteristics together with some more specific parameters allow scientists to distinguish spectral characteristics of a microbial aerosol from same parameters of an aerosol of nonbiological origin.

 

 

The development of Russian engineers consists of several separate units and works according principles of flow-optical analysis of particles. Aerosol enters a flow chamber, and then all its particles cross the probe light beam one by one. Aerosol particles reflect light, and these signals move to photoelectric detectors first, and then proceed to an amplifier, which forwards them to information processing unit. This unit considers all data, submitted by the system, and then “informs” a researcher whether protein aerosol is present in the air and what its real-time concentration is.

Scientists performed a series of tests in the static chamber of certified aerosol static and dynamic testing stand in order to see where their creation worked properly. Those experiments proved that new joint development of Russian physicists, chemists and engineers is able to measure mass concentration of biological aerosol in real time mode. Further investigation should doubtlessly cover issues of identification of microbes, present in the air, and finding potential pathogens.

Source: Russian Science News

Kizilova Anna