(277f) Analysis of Pneumonia Associated Volatile Organic Compounds from Bacteria Culture Using Synthesized TiO2 Nanotube Array Sensor and Gas Chromatography/Mass Spectrometry

A vast variety of volatile
organic compounds (VOCs) are present in human breath¹.
Microorganisms causing diseases like pneumonia release unique VOCs that are not
present in healthy human breath, or they decrease or increase the concentration
depending on the pathological state of the patient. Each year about one million
people are affected by pneumonia in the Unites States². Early
screening for pneumonia would help prevent severe sickness and potential
hospitalization later as it would allow healthcare professionals to administer
treatment quickly. Monitoring the presence of pneumonia VOCs in the patient’s
breath is potentially a fast approach for rapid pneumonia screening or
diagnosis. 

Various VOCs have been reported
in literature to be present in the breath of pneumonia patients³
such as heptane, ethanol, and acetone. 
Pneumonia is caused by a variety of different bacteria consortium which
result in different VOC profiles.  Two
bacteria known to be associated with pneumonia are normal">Streptococcus pneumonia and normal">Haemophilus influenzae. In this work we cultured these
microorganisms and analyzed the headspace to confirm and establish the VOC
profile using gas-chromatography and mass-spectrometry (GCMS).

Titanium dioxide (TIO2) nanotube
arrays have been synthesized to detect the mixture of heptane and ethanol in
liquid and gas phase with the purpose of utilizing the nanotube arrays as a
low-cost screening tool for pneumonia. 
Our group’s previous works show that cobalt functionalized titanium
dioxide nanotubes sensors at specific biased voltages detect the presence of
tuberculosis VOCs^4-5. Results from testing non-functionalized
titanium dioxide nanotubes and nickel functionalized nanotubes to detect the
presence of heptane and ethanol will be presented. Figure.1 shows the
preliminary amperometric results of testing a
non-functionalized TiO2 sensor in the presence of heptane at 1.5 V. The sensor
was exposed to nitrogen gas throw liquid heptane and plain nitrogen gas for a
negative check. At a positive biased voltage of 1.5 V, the sensor
current-change during heptane exposure was positive. While the current-change
was negative when plain nitrogen gas was in contact with the sensor. The
experiment is conducted three times.

In this work, GCMS analysis from
the VOCs produced by pneumonia cultured bacteria and TiO2 sensors response to
pneumonia mimic breath samples will be presented.

References:

mso-list:l0 level1 lfo1"> Calibri;mso-bidi-theme-font:minor-latin">1.       Jill D. Fenske & Suzanne E.
Paulson (1999) Human Breath Emissions of VOCs, Journal of the Air & Waste
Management Association, 49:5, 594-598, DOI: 10.1080/10473289.1999.10463831

mso-list:l0 level1 lfo1"> Calibri;mso-bidi-theme-font:minor-latin">2.       Center of Disease Control and Prevention

3.      
PoulineMvan
Oort, Pedro Povoa, Ronny
Schnabel, et al. The potential role of exhaled breath analysis in the
diagnostic process of pneumonia—a systematic review. J. Breath Res. 12 (2018)
024001

4.      
Bhattacharyya D, Smith YR, Misra M, Mohanty SK.
Electrochemical detection of methyl nicotinate biomarker using functionalized
anodized titania nanotube arrays. Materials Research
Express 2015;2(2):025002.

5.      
Bhattacharyya D, Smith YR, Mohanty SK, Misra M. Titania Nanotube Array Sensor for Electrochemical Detection
of Four Predominate Tuberculosis Volatile Biomarkers. Journal of The
Electrochemical Society 2016;163(6):B206-B214.