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Recent Advances in Electrophotonic Imaging
Published in Len Wisneski, The Scientific Basis of Integrative Health, 2017
Len Wisneski, Konstantin Korotkov, Len Wisneski
There are many discussions about water structuralization under the influence of inclusions. Structured water is characterized by ordering water molecules that generally occur next to hydrophilic interfacial surfaces, where layers of ordered water are found with properties that differ from those of bulk water.58 This water has many physical properties, which differ from ordinary bulk water,59 in particular that extended water clusters aggregating in an autostabilizing network can grow to macroscopic proportions.60 This leads to the formation of reactive oxygen species in water,61 which increases the concentration of free electrons in water and may result in an increased signal of stimulated photon emission registered by an EPI instrument.
Correlations between pore textures of activated carbons and Langmuir constants – case studies on methylene blue and congo red adsorption
Published in Toxin Reviews, 2022
Fadina Amran, Muhammad Abbas Ahmad Zaini
Affinity indicates the strength between solid surface and dye molecules. It is directly proportional to adsorption capacity at low concentration, where dye molecules are adsorbed to a greater extent. The phosphoric acid-activated bacterial yielded a strong affinity of 10 000 L/g with reasonably high uptake of 500 mg/g (Khamkeaw et al.2019). Likewise, a 1496 m2/g surface area of potassium carbonate-activated chengal wood sawdust renders a 1030 L/g affinity, leading to 423 mg/g of adsorption capacity (Foo and Hameed 2012). The abundance of oxygen-containing groups such as hydroxyl and carbonyl groups, enhances the electrostatic interactions with the positively charged methylene blue molecules for high removal capacity as well as affinity (Zamani and Tabrizi 2015). However, the reduced uptake of dye is due to the mechanism of water adsorption. Water adsorbs through hydrogen bonding, causing the formation of water clusters surrounding the hydrophilic oxygen groups; the built-up of water clusters clogs the mesopores, so reducing the availability of active sites .
Collective excitations in α-helical protein structures interacting with the water environment
Published in Electromagnetic Biology and Medicine, 2020
Vasiliy N. Kadantsev, Alexey Goltsov
As shown in the model, the collective vibration modes are excited through the energy pumping to the system from fluctuating water environment (see Equation (39)). It is suggested that the vibrational energy can be channeled to the protein through the vibrational interaction of the side- chains with the water molecules surrounding the protein. According to the model, the motion of the side-chain residues is correlated with the motion of the hydration shell and bulk water molecules that defines the internal dynamics of the α-helical proteins. In general, the molecular mechanisms of energy transfer from the solvent-exposed side-chains on the protein surface to their internal protein motion are the subject of intense experimental and theoretical investigation (Agarwal 2006), (Wang et al., 2018). As the results of this study, the vibrational energy transport pathways within enzymes were established which are capable of transferring required energy to the catalytic-site from dynamical fluctuations of the solvent. The mechanisms of energy pumping and transferring can be determined by the interaction of ordered water clusters bound to the hydration shell of proteins and polar amino acid residues (Goncharuk et al. 2017). Additionally, the hydrogen bond networks of water molecules which possess the collective vibrational sub-picosecons dynamics and propagating phonon-like modes in terahertz and IR spectra can also contribute to this mechanism (Conti Nibali and Havenith 2014; Niessen et al. 2017b).
Potential application of mass spectrometry imaging in pharmacokinetic studies
Published in Xenobiotica, 2022
Chukwunonso K. Nwabufo, Omozojie P. Aigbogun
Highly sensitive analytical methods are critical for performing PK studies because drugs and metabolites are typically present in biological samples at low concentrations and matrix interference could further reduce their ion intensity due to competing ionisation effects. Ion source plays a critical role in determining the sensitivity of MS methods because analytes of interest in biological samples need to be sufficiently ionised to be separated by the mass analyser and detected accordingly. Ionisation efficiency is a limiting factor for several ion sources; for instance, ionisation efficiencies for MALDI and SIMS are quite low (between 10−5 and 10−4), creating an opportunity for advancement (Gilmore et al. 2019). Additionally, ion losses from the source to the mass analyser and from the mass analyser to the detector further compound sensitivity issues for MS methods. Some progress has been made with respect to increasing MALDI ion yield by improving the wavelength of the MALDI laser (Soltwisch et al. 2012; Niehaus et al. 2017). Derivatization of samples using reactive matrix materials is an intriguing strategy to mitigate interferences resulting from low molecular weight matrix compounds, ion suppression, or analytes with low inherent ionisation efficiencies (Gilmore et al. 2019). Following this approach, the ion abundance of neurotransmitters was significantly improved (Shariatgorji et al. 2014). The gas cluster ion beam chemistry in SIMS can be changed (Winograd 2018), and at the moment, water cluster ion beams provide the most notable improvement in ion yield for biomolecules (Sheraz née Rabbani et al. 2015). Postionization techniques that allow neutral molecules to be ionised after being desorbed, increasing ion yield may significantly improve the sensitivity of MSI analyses and should be considered (Gilmore et al. 2019).