Analysis of the volatile compounds’ condensate exhaled air “electronic nose” based on piezoelectric sensor to assess the status of calves

Abstract

The article discusses general principles of obtaining diagnostic information using eight chemical piezoelectric gas sensors with nanostructural coverings from exhaled breath condensate for health assessment of the upper respiratory tract of pre-month-old calves. Multidimensional information of an e-nose can be presented in various numeric and visualized matrices, characteristics of which are an integral analytical signal of the sensor array. The research devoted to the search for the techniques of extracting analytical information from multidimensional e-nose data to assess upper respiratory tract state from the appearance of the first sign of respiratory disease to tracheobronchitis and bronchopneumonia. The piezoelectric sensor array is characterized by high sorption activity with priority biomolecules (which are the markers of the abnormal metabolic processes), low cost along with reliable repeatability of sorption properties from batch to batch, the simplicity of application, and fast response and recovery time. Here we present the results of simple algorithms used for assessment of upper respiratory tract state by a 2-minute analysis of odour over 1-ml biosample without sample preparation. It was shown that traditional quantitative parameters of e-nose are not adequate for simultaneous sample grouping and volatile compounds qualitative composition establishing. The additionally calculated sorption parameters Aij are more informative in the analysis of biosamples volatile: using for identification of volatile biomarkers, describe the health state correlating with clinical diagnosis. The sequence of information processing: signals of each sensor, integral characteristic, “visual prints,” additional sorption parameters–allows assessing the calf health virtually in situ without transporting samples to specialized laboratories.

Bovine Respiratory Syncytial Virus (BRSV) Infection Detected in Exhaled Breath Condensate of Dairy Calves by Near-Infrared Aquaphotomics

“…More volatile compounds, as well as some chemical elements, have been detected at significant levels in bovine EBC using an electronic nose, finding potential biomarkers for animals with respiratory disease [31] that can be associated with the aquaphotomics profile found in the present study. The compounds 1,2-dimethylcyclohexylamine (C 8 H 17 N), aliphatic acids C 2 -C 5 , ammonia (NH 3 ), cyclohexylamine (C 6 H 13 N), ethandal, methylamine (CH 3 NH 2 ), methylglyoxal (C 3 H 4 O 2 ), and pyridine-carbaldehyde (C 6 H 5 NO) were detected in calves with respiratory disease in comparison to healthy calves that only exhaled alkyl-, cyclic amines [31]. Chemical elements evaluated in the EBC from 18 sick Holstein calves with bronchopneumonia showed a significant decrease (p < 0.05) in Se and Zn, and an increase in Al, Co, Mn, Mo, Na, P, Pb, and Sn in comparison to the EBC from 12 healthy subjects [16].…”

“…Other volatile organic compounds, such as acetaldehyde (C 2 H 4 O) and decanal (C 10 H 20 O), have also been reported in the EBC from steers (n = 3) diagnosed with BRDC by clinical signs (VCD), while heptane (C 7 H 16 ), octanal (C 8 H 16 O), 2,3-butadione (C 6 H 10 ), hexanoic acid (C 6 H 12 O 2 ), and phenol (C 6 H 6 O) were associated with healthy animals (n = 3) [14]. More volatile compounds, as well as some chemical elements, have been detected at significant levels in bovine EBC using an electronic nose, finding potential biomarkers for animals with respiratory disease [31] that can be associated with the aquaphotomics profile found in the present study. The compounds 1,2-dimethylcyclohexylamine (C 8 H 17 N), aliphatic acids C 2 -C 5 , ammonia (NH 3 ), cyclohexylamine (C 6 H 13 N), ethandal, methylamine (CH 3 NH 2 ), methylglyoxal (C 3 H 4 O 2 ), and pyridine-carbaldehyde (C 6 H 5 NO) were detected in calves with respiratory disease in comparison to healthy calves that only exhaled alkyl-, cyclic amines [31].…”

“…Exhaled breath condensate (EBC) can be collected non-invasively and has been used to monitor respiratory disease in humans and animals [26][27][28][29]. EBC contains metabolites or substances such as adenosine, ammonia, cytokines (small proteins ~5-25 kDa), hydrogen peroxide, isoprostanes (free radical lipid peroxidation of arachidonate), leukotriene B4, nitrogen oxides (NO 2 − and NO 3 − ), and peptides demonstrated to be helpful in evaluating oxidative stress and inflammatory response in the respiratory system [26,30], and which have been detected by GC-MS [14,16,[31][32][33]. We propose that with these known indicators of inflammation evident in EBC, NIRS-based aquaphotomics coupled with chemometrics may provide a mode of rapid analysis of respiratory disease that can be conducted in the field.…”