Body fluids and electrolytes
Peate Ian, Dutton Helen in Acute Nursing Care, 2020
An electrolyte is a substance which develops an electrical charge when dissolved in water, by gaining or losing one or more electrons. Electrolytes which develop a positive charge in solution, having lost one or more electrons, are called cations. The primary extracellular cation is sodium (Na+) whereas the primary intracellular cation is potassium (K+). Electrolytes which develop a negative charge in solution by gaining one or more electrons are called anions; the primary extracellular anions are the chloride (Cl−) and bicarbonate (HCO3−) ions, whereas the primary intracellular anion is the phosphate ion (PO43-). The number of cations and anions in body fluids, as measured in millimoles per litre (mmol/L), is always equal because positive and negative charges must be equal. All solutions are electrically neutral, and this balance is called electroneutrality. It must be remembered that this is a dynamic homoeostatic state, depending on the acidity of the body; H+ and HCO3− ions will combine and dissociate as needed to maintain a stable pH (Marieb and Hoehn 2019).
Nutrition for health and sports performance
Nick Draper, Helen Marshall in Exercise Physiology, 2014
An ionic bond is formed between two atoms when one of the atoms donates an electron to another, thus completing the outer shell of electrons for each and creating a stable chemical product. An example of this can be found in Figure 2.3 where chlorine (Cl) accepts one electron from sodium (Na). By doing this Cl becomes a negatively charged chloride ion (Cl−) as it has more electrons than protons and Na becomes a positively charged sodium ion (Na+) because it has one electron fewer. Atoms that lose electrons and become positively charged are called cations (to remember this think of the t as + and positive) and those that accept electrons and become negatively charged ions are called anions (think of the n as n egative). The resultant compound for this example is sodium chloride (NaCl) or table salt. It is this compound in our sweat that gives sweat a salty taste.
An overview of fluids and electrolytes
Bernie Garrett in Fluids and Electrolytes, 2017
An electrolyte is a substance that separates in solution into its ionic components and is capable of conducting electricity.6 These molecules have an electric charge: cations are ions (or groups of ions) having a positive charge and they move towards a negatively charged electrode in electrolysis (chemical decomposition produced by passing an electric current through a liquid). Anions migrate towards the negative pole in electrolysis. In the body, these charges generally balance out within the intracellular and extracellular fluid compartments (see Table 1.1). Electrolytes may be transported around the body by active or passive processes. Passively, electrolytes in solution may be transported by diffusion or carried along as solutes in fluid flow (solvent, or sometimes referred to as solvent drag).
ION cyclotron resonance: Geomagnetic strategy for living systems?
Published in Electromagnetic Biology and Medicine, 2019
One of the many puzzling things about the long list of ion cyclotron resonance reports, apart from the overarching problem of exactly how cyclotron resonance paths can be obtained in the fairly dense fluids found in biological systems, is the difficulty in considering an effect that is dependent on the Lorentz force, a force that is nonexistent for charged particles that are not in motion. The Lorentz force explicitly includes the vector term v x B, which not only provides a direction for the resulting force, namely perpendicular to both v and to B, but it also requires that the charged particle is moving to begin with. There is evidence for inherent motion of the net positive charge associated with simple cations such as Ca2+, K+, Mg2+, under conditions where ICR effects have been reported. In these cases one can simply argue that charge transport occurs because the ion itself is in motion, a statement consistent with the accepted biological notion of ion transport as a signaling mechanism. However as mentioned above, ICR is also observed in much more massive charged molecules that are not biologically effective because of their transport but rather because they contribute electrically positive charge to specific reactions. We conclude that ICR effects do not arise solely as a secondary consequence of ion transport.
The influence of physicochemical properties on the reactivity and stability of acyl glucuronides†
Published in Xenobiotica, 2018
Patrick Camilleri, Akshay Buch, Brandi Soldo, Andrew J. Hutt
The inclusion of a carboxylic group in a chemical structure also allows the formation of the salt forms of the negatively charged drug. The predominant cation that has been used is sodium, with a much lower number of salts formed with calcium, tromethamine, or potassium. Weakly acidic drugs delivered as salts that contain these cationic counter ions aid formulation and are normally characterised by improved physico-chemical properties such as enhanced solubility, a higher rate of dissolution and, as a result, greater cell permeability. Moreover, the biological efficacy of the salt form can show a marked improvement over that of the free acid form of the drug substance. Some examples of drug substances that contain a carboxylic group and that are marketed worldwide as their salt forms include: valproate sodium, naproxen sodium, diclofenac sodium, diclofenac potassium, dexketoprofen trometamol and ketorolac trometamol (tromethamine) and resuvastatin calcium.
Visualizing phosphatidylcholine via mass spectrometry imaging: relevance to human health
Published in Expert Review of Proteomics, 2018
Jenny Leopold, Yulia Popkova, Kathrin M. Engel, Jürgen Schiller
When the pulsed laser beam hits the sample (co-crystals between matrix and analyte), its energy is absorbed by the matrix that is present in excess over the analyte. Consequently, the matrix is vaporized, carrying intact analyte molecules into the vapor phase. During the expanding process of this gas cloud, ions (e.g. H+ and Na+) are exchanged between the matrix and the analyte, leading to the formation of charged analyte molecules (‘adducts’). Since potassium ions are abundant in cells, biological samples often also show K+ adducts [22]. Besides cation generation, anions can also be generated by abstracting H+ or Na+ from the analyte. The ratio between the cation and the anion yield is determined by the (gas phase) acidities of the analyte and the matrix. Fundamental aspects of the ion formation process were recently comprehensively reviewed [23]. Using MALDI MS singly charged ions are primarily generated, which makes the interpretation of these mass spectra very simple and is therefore a big advantage of MALDI-TOF MS compared to ESI MS [24]. The other benefit of MALDI-TOF MS is the higher tolerance toward impurities (such as salts) which is even more important if a purification of the sample prior to MS characterization is not possible. Therefore, MALDI-TOF MS is the method of choice to analyze crude (lipid) mixtures and can also be used for MS imaging (MSI) experiments.
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