Neurotransmitter Biomarkers

Screening of Potential Stress Biomarkers in Sweat Associated with Sports Training

“…Before the methodology development and optimization for biomarker identification in the sweat samples, it was necessary to consider the chemical properties of the target biological molecules. The previous research on the function of the eccrine gland [ 20 ], on the artificial sweat composition [ 33 ] and on the information about stress biomarkers related with exercise [ 11 , 14 – 16 , 18 , 19 , 21 , 22 ] were the default knowledge of the state of the art for the decision making for selecting the initial biomarkers to be detected in a sweat profile. Taking in consideration the literature available data, the chemical properties and the more recent available techniques [ 14 , 16 , 17 , 21 , 24 , 25 , 34 ], neurotransmitter (NT) biomarkers and other biomarkers that may be related with stress in physical training and/or associated with renal, liver and heart health functions [ 16 , 22 , 27 ] were considered as the primary target molecules for identification.…”

“…UHPLC, using a principle like high pressure liquid chromatography (HPLC), yields a significant improvement in the rapid separation of analyte via its smaller particle-size stationary phase and ultra-high-pressure pumps. It is therefore better suited for NT separation than conventional HPLC [ 16 ].…”

“…In the sweat sample clean up preparation for analysis, salts and proteins contained in the samples are not appropriate for ESI source causing signal suppression. For instance, the sensitivity of ESI is not favoured by highly polar and small molecules, such as NTs [ 16 , 35 ] that are more susceptible to ion suppression. These considerations highlight the importance of sample pre-treatment prior analysis.…”

“…The ability to use sweat as an analytical fluid provides the opportunity for non-invasive sampling for early and continuous diagnosis. Depending on the analytical techniques, the sampling and preparation for analysis of sweat may be easier and faster by comparison with other biological fluids, in particular blood [ 16 , 17 ]. Clinical use is currently very restricted, as there is only a single validated test to detect cystic fibrosis [ 12 , 17 , 18 ].…”

“…The initial strategy was to define which potential target molecules may be under concern. A bibliographic research on the state of the art concerning the function of the eccrine gland [ 20 ] together with reported artificial sweat composition [ 16 ] and data of already known potential target biological molecules [ 11 , 12 , 14 – 16 , 18 , 19 , 21 – 23 ] was the method to predict the molecules chemical and biological families that could be found in the screening. An example is some neurotransmitters (NTs) that were already associated with stress (e.g.…”