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Breathomics and its Application for Disease Diagnosis: A Review of Analytical Techniques and Approaches
Published in Raquel Cumeras, Xavier Correig, Volatile organic compound analysis in biomedical diagnosis applications, 2018
David J. Beale, Oliver A. H. Jones, Avinash V. Karpe, Ding Y. Oh, Iain R. White, Konstantinos A. Kouremenos, Enzo A. Palombo
Some researchers collect exhaled breath condensate (EBC), which is a biofluid obtained non-invasively after collecting and cooling the exhaled air (Baraldi et al., 2009; Carraro et al., 2007; Ibrahim et al., 2013). Typically, the condensate is collected via a sampling device fitted with a condenser and a saliva trap. A major advantage of analyzing EBC is that it captures both volatile and non-volatile metabolites (Nobakht et al., 2015). The EBC is collected over a period of 15 or more minutes and its composition is believed to reflect that of the fluid lining the airways (Carraro et al., 2007). Exhaled breath vapor/condensate (EBV/EBC) collection, has been described in a widely cited research paper by Martin et al. (2010). The study involved the use of a solid phase microextraction (SPME) fibre fitted inside the commercial breath collection device, namely the RTubeTM. The SPME adsorbed sample was then desorbed to a gas chromatography mass spectrometry (GC-MS) assembly for analysis. The test indicated a presence of limonene and related metabolites such as pinene, myrcene and terpinols from breath samples of individuals who had consumed lemonade. The study also showed a great potential for detecting compounds more relevant to medical diagnosis.
Alternaria
Published in Dongyou Liu, Laboratory Models for Foodborne Infections, 2017
Alicia Rodríguez, Andrea Patriarca, Mar Rodríguez, María Jesús Andrade, Juan José Córdoba
For the evaluation of mycotoxin production by Alternaria, analytical methods based on chromatography are often used for their extraction and detection from the food matrices (Figure 30.1). Usually, a solvent extraction from solid foods with organic solvents, such as dichloromethane, methanol, acetonitrile, or ethyl acetate, is required, although an acidic extraction or a further acidification step is preferable to increase the recovery for TeA.33 Cleanup procedures are necessary when a complex matrix is involved. Successive steps of solvent partitioning, solid phase extraction (SPE) columns, or solid phase microextraction are common cleanup techniques used in most food matrices.24
History and Sources of Essential Oil Research
Published in K. Hüsnü Can Başer, Gerhard Buchbauer, Handbook of Essential Oils, 2020
In static HS analysis, the liquid or solid sample is placed into a vial, which is heated to a predetermined temperature after sealing. After the sample has reached equilibrium with its vapor (in equilibrium, the distribution of the analytes between the two phases depends on their partition coefficients at the preselected temperature, the time, and the pressure), an aliquot of the vapor phase can be withdrawn with a gas-tight syringe and subjected to gas chromatographic analysis. A simple method for the HS investigation of herbs and spices was described by Chialva et al. (1982), using a blender equipped with a special gas-tight valve. After grinding the herb and until thermodynamic equilibrium is reached, the HS sample can be withdrawn through the valve and injected into a gas chromatograph. Eight of the obtained capillary gas chromatograms are depicted in the paper of Chialva and compared with those of the respective essential oils exhibiting significant higher amounts of the more volatile oil constituents. However, one of the major problems with static HS analyses is the need for sample enrichment with regard to trace components. Therefore, a concentration step such as cryogenic trapping, liquid absorption, or adsorption on a suitable solid has to be inserted for volatiles occurring only in small amounts. A versatile and often-used technique in the last decade is solid-phase microextraction (SPME) for sampling volatiles, which will be discussed in more detail in a separate paragraph. Since different other trapping procedures are a fundamental prerequisite for dynamic HS methods, they will be considered in the succeeding text. A comprehensive treatment of the theoretical basis of static HS analysis including numerous applications has been published by Kolb and Ettre (1997, 2006).
Evaluation of blood BTEX levels in fuel stations workers using vortex-assisted dispersive liquid-liquid microextraction based on deep eutectic solvent followed by gas chromatography flame-ionization detector
Published in Toxin Reviews, 2023
Mari Ataee, Toraj Ahmadi Jouybari, Hawre Lateef Ahmed, Hadi Ahmadi Jouybari, Meghdad Pirsaheb, Nazir Fattahi
Sample preparation play an important role in purifying matrix interference and enrichment of target analytes prior to HPLC analysis. Therefore, an efficient and effective extraction step is necessary to obtain the highest accuracy in the determination of small amounts of BTEX compounds in blood samples. Liquid–liquid extraction (LLE) (Yu et al. 2022), solid phase extraction (SPE) (Raza et al. 2018), solid-phase microextraction (SPME) (Fustinoni et al. 1999), liquid-phase microextraction (LPME) (Sarafraz-Yazdi et al. 2008), and dispersive liquid–liquid microextraction (DLLME) (Assadi et al. 2010) are widely used in the extraction of BTEX in various samples. Recently, the synthesis of green, environmentally friendly, and inexpensive solvents called deep eutectic solvents (DESs) have attracted much attention in the field of green chemistry. DES includes hydrogen bond acceptor (HBA) and hydrogen bond donor (HBD), which are bound by hydrogen bonding at suitable temperatures and specific proportions (Malaeke et al. 2018, Ahmadi-Jouibari et al. 2021, Fattahi et al. 2022a). A simple synthesis process and good biocompatibility are other advantages of DES compared to ionic liquids and toxic organic solvents. Until now, these solvents have been used for the extraction and preconcentration of various organic and inorganic compounds (Ataee et al. 2020, Nemati et al. 2022).
Identification of odor biomarkers in irradiation injury urine based on headspace SPME-GC-MS
Published in International Journal of Radiation Biology, 2021
Xin Wu, Tong Zhu, Hongbing Zhang, Lu Lu, Xin He, Changxiao Liu, Sai-jun Fan
Urine is stable, easy to collect and noninvasive, and it is widely used in clinical practice. However, due to low concentrations and various interferences including water, the analysis of VOCs is restricted, so it is very important to enrich the sample. Solid phase microextraction (SPME) has high extraction efficiency, a high pre-concentration factor and is easily automated (Ghorbani et al. 2019; Jalili et al. 2020). These advantages make it very popular, especially in combination with gas chromatography-mass spectrometry (GC-MS) with high resolution and high sensitivity, which greatly promotes the analysis of VOCs in urine. Nowadays, metabolomics based on SPME-GC-MS has been used for urine VOCs analysis of many diseases, such as cancer, autism and gastrointestinal diseases (Cozzolino et al. 2014; Gundamaraju et al. 2017; Deev et al. 2020).
Ultra-preconcentration of common herbicides in aqueous samples using solid phase extraction combined with dispersive liquid–liquid microextraction followed by HPLC–UV
Published in Toxin Reviews, 2021
Toraj Ahmadi-Jouibari, Negar Noori, Kiomars Sharafi, Nazir Fattahi
Sample preparation is one critical step of an analytical procedure and an integral part of any analysis. Optimized sample preparation is necessary, not only to reduce the time taken but because each step adds a potential source of error. The amount of sample preparation needed depends on the sample matrix and the properties and level of analyte to be determined. The determination of trace contaminants in complex matrices, such as biological samples and highly saline solutions, often requires extensive sample extraction and preparation regimes prior to instrumental analysis (Ma et al. 2018, 2019). Several techniques have been developed for the extraction and preconcentration of contaminants from aqueous samples, such as solid-phase extraction (SPE) (Rivoira et al. 2015, Wang et al. 2019), solid-phase microextraction (SPME) (Mirzajani et al. 2017, Pei et al. 2019), liquid–liquid extraction (LLE) (Duca et al. 2014), continuous sample drop flow microextraction (CSDFME) (Karimaei et al. 2017), homogeneous liquid–liquid extraction (HLLE) (Ebrahimzadeh et al. 2007), and liquid-phase microextraction (LPME) (Yilmaz and Soylak 2016, Reclo et al. 2017).