## 3 Metabolic Profiling of Urine: Recent Trends
### MEPS and SPME Advantages for the Metabolic Profile of Urine
#### 3.2.1 CVDs
\begin{table}
\begin{tabular}{l c c c c} \hline \hline \multirow{2}{*}{**Target diseases or analytes**} & **LOD** & **LOQ** & \multirow{2}{*}{**Analytical method**} & \multirow{2}{*}{**Reference**} \\ \cline{2-2} \cline{5-5}  & **(ng\(\cdot\)mL\({}^{-1}\) by default)** & & & \\ \hline
**NDDs** & & & & \\ \hline \hline \end{tabular} \
\begin{tabular}{l c c c} \hline \hline \multirow{2}{*}{
\begin{tabular}{l} Selegiline and desmethylselegiline (PD drugs) \\ \end{tabular} } & \multirow{2}{*}{0.01–0.05} & \multirow{2}{*}{0.05–20} & \multirow{2}{*}{SPME/GC–MS} & [97] \\ \hline
**Catecholamines (elevated in several CVDs an NDDs)** & & & \\ \hline \hline \end{tabular} \
\begin{tabular}{l c c c} \hline \hline \multicolumn{2}{l}{Serotonin, dopamine and noradrenaline} & \multicolumn{1}{c}{2–20} & \multicolumn{1}{c}{5–50} & \multicolumn{1}{c}{MEPS/LC-ECD} & [98] \\ \hline \hline \multicolumn{2}{l}{Dopamine and serotonin} & \multicolumn{1}{c}{1} & \multicolumn{1}{c}{50} & \multicolumn{1}{c}{MEPS/LC-MS/MS} & [99] \\ \hline \hline \multicolumn{2}{l}{Dopamine} & \multicolumn{1}{c}{1.2} & \multicolumn{1}{c}{4.0} & \multicolumn{1}{c}{SPME/LC-ESI-MS/MS} & [100] \\ \hline \hline \multicolumn{2}{l}{Dopamine, epinephrine and norepinephrine} & \multicolumn{1}{c}{4.8–7.4 (nM)} & \multicolumn{1}{c}{-} & \multicolumn{1}{c}{SPME/EC-UV} & [101] \\ \hline \hline \multicolumn{2}{l}{non-polar heterocyclic amines (high carcinogenic potential)} & \multicolumn{1}{c}{1.6–5.6} & \multicolumn{1}{c}{5.5–18.7} & \multicolumn{1}{c}{MEPS/CLC-FLD} & [102] \\ \hline \hline \end{tabular}
\begin{tabular}{l} Abbreviations: 5-HMUra, 5-hydroxymethyluracil; 5-HIAA, 5-hydroxyindolacetic acid 8-oxodG, 8-oxo-7,8-dihydro-2’-deoxyguanosine; AD, Alzheimer’s disease; ALS, amyotrophic lateral sclerosis; CAR, carnitine; CEC, Capillary electrochromatography, CLC-FLD, capillary liquid chromatography - fluorometric detection; CVDs, cardiovascular diseases; GC-MS, gas chromatography-mass spectrometry, GC-QqQ-MS/MS, gas chromatography-triple quadrupole-mass spectrometry; HPLC-PDA, high performance liquid chromatography with photodiode array detection; HVA, homovanillic acid; KG, ketoglutaric acid, LC-ED, high performance liquid chromatography coupled to electrochemical detection; LC-ESI/MS, liquid chromatography coupled to an electrospray ionization mass spectrometer; LC-CD, liquid chromatography with colorimetric detection; LC-FLD, liquid chromatography with fluorescence detection; LC-MS/MS, liquid chromatography-tandem mass spectrometry; LC-UV, liquid chromatography coupled to an ultraviolet detector; LOD, limit of detection; LOQ, limit of quantification; METs, microextraction techniques; NDDs, neurodegenerative diseases; ODs, oncologic diseases; PD, [PERSON]’s disease; SPME, solid-phase microextraction; μPESI-MS/MS, micropillar array electrospray ionization mass spectrometry; VMA, vanilmandelic acid; VOCs, volatile organic compounds. \\ \end{tabular}
\end{table} 
Table 2: _Cont._extraction [70; 71; 72; 73; 74; 108] or ELISA, although the reliability of this approach is strongly affected by antibody cross-reactivity issues [109]. The utilization of MEPS would certainly raise the analytical performance obtained in the methods described, allowing for a deeper understanding of the power of F2-isoprostanes as CVD biomarkers. Using this extraction procedure, [PERSON] _et al._[110] reported another putative correlation between oxidative damage and CVDs. Although very preliminary, their results suggest a positive correlation between the urinary levels of the oxidatively damaged DNA adducts, 8-oxo-7,8-dihydro-29-deoxyguanosine (8-oxodG) and 5-hydroxymethyluracil (5-HMUra) and CVDs risk progression. [PERSON] _et al._[76], in turn, focus their studies on \(\alpha\)-ketoglutaric acid (KG), L-carnitine (CAR) and acetyl-L-CAR, which are molecules that have an important role in cardiac cell metabolism, this being very important for the outcome of a cardiac injury.