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Han GE, Priefer R. A systematic review of various pK a determination techniques. Int J Pharm 2023; 635:122783. [PMID: 36858133 DOI: 10.1016/j.ijpharm.2023.122783] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2022] [Revised: 02/19/2023] [Accepted: 02/23/2023] [Indexed: 03/02/2023]
Abstract
The pKa values of functional groups is crucial in determining the pharmacokinetic properties of a drug, affecting its absorption and thus bioavailability. This physicochemical property is also vital for the designing of drug excipients and vehicles. There are currently 13 known methods of determining a pKa value, namely: potentiometric titration, spectrometry, fluorometry, NMR, HPLC, conductometry, electrophoresis, voltammetry, solubility, partition coefficient, calorimetry, computational, and surface tension. Some of these techniques are more widely utilized and well-established compared to others, with each having their inherent advantages and disadvantages. This review discusses each of the aforementioned techniques with emphasis on their pros and cons.
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Affiliation(s)
- Gi Eun Han
- Massachusetts College of Pharmacy and Health Sciences, Boston, MA, United States
| | - Ronny Priefer
- Massachusetts College of Pharmacy and Health Sciences, Boston, MA, United States.
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2
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Akino S, Yasujima T, Yamashiro T, Yuasa H. Disrupted in renal carcinoma 2 (DIRC2/SLC49A4) is an H +-driven lysosomal pyridoxine exporter. Life Sci Alliance 2023; 6:e202201629. [PMID: 36456177 PMCID: PMC9719028 DOI: 10.26508/lsa.202201629] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2022] [Revised: 11/20/2022] [Accepted: 11/21/2022] [Indexed: 12/02/2022] Open
Abstract
Disrupted in renal carcinoma 2 (DIRC2) has gained interest because of its association with the development of renal cancer and cosegregation with a chromosomal translocation. It is a member of the SLC49 family (SLC49A4) and is considered to be an electrogenic lysosomal metabolite transporter; however, its molecular function has not been fully defined. To perform a detailed functional analysis of human DIRC2, we used a recombinant DIRC2 protein (DIRC2-AA), in which the N-terminal dileucine motif involved in its lysosomal localization was removed by replacing with dialanine for redirected localization to the plasma membrane, exposing intralysosomal segments to the extracellular space. The DIRC2-AA mutant induced the cellular uptake of pyridoxine (vitamin B6) under acidic conditions when expressed transiently in COS-7 cells. In addition, uptake was markedly inhibited by protonophores, indicating its function through an H+-coupled mechanism. In separate experiments, the transient overexpression of unmodified DIRC2 (tagged with HA) in human embryonic kidney 293 cells reduced cellular pyridoxine accumulation induced by transiently introduced human thiamine transporter 2/SLC19A3 (tagged with FLAG), a plasma membrane thiamine transporter that also transports pyridoxine. The cellular accumulation of pyridoxine in Caco-2 cells as a cell model was increased by the knockdown of endogenous DIRC2. Overall, the results indicate that DIRC2 is an H+-driven lysosomal pyridoxine exporter. Its overexpression leads to a reduction in cellular pyridoxine accumulation associated with reduced lysosomal accumulation and, conversely, its suppression results in an increase in lysosomal and cellular pyridoxine accumulation.
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Affiliation(s)
- Shogo Akino
- Department of Biopharmaceutics, Graduate School of Pharmaceutical Sciences, Nagoya City University, Nagoya, Japan
| | - Tomoya Yasujima
- Department of Biopharmaceutics, Graduate School of Pharmaceutical Sciences, Nagoya City University, Nagoya, Japan
| | - Takahiro Yamashiro
- Department of Biopharmaceutics, Graduate School of Pharmaceutical Sciences, Nagoya City University, Nagoya, Japan
| | - Hiroaki Yuasa
- Department of Biopharmaceutics, Graduate School of Pharmaceutical Sciences, Nagoya City University, Nagoya, Japan
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3
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Liu M, Liu WD, Li YX. Solubility, Hansen solubility parameter, molecular simulation and apparent thermodynamic analysis of 5-Fluorouracil in four binary solvents. J Mol Liq 2022. [DOI: 10.1016/j.molliq.2022.119759] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
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4
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Liu WD. Thermodynamic modelling, Hansen solubility parameter and solvent effect of palbociclib in fourteen pure solvents at different temperatures. J Mol Liq 2022. [DOI: 10.1016/j.molliq.2022.119059] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
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5
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Liu WD. Dissolution behavior of 5-fluorouracil in fourteen neat solvents: Solubility, correlation, solvent effect, Hansen solubility parameter, molecular simulation and thermodynamic analysis. J Mol Liq 2022. [DOI: 10.1016/j.molliq.2022.118733] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
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6
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Liu WD, Guo HJ, Li ZY. Measurement, correlation of solubility and thermodynamic properties analysis of 5,5′-bis(2,4,6-trinitrophenyl)-2,2′-bis(1,3,4-oxadiazole) in different mono solvents. J Mol Liq 2022. [DOI: 10.1016/j.molliq.2021.118226] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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7
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Liu WD, Li YX, Cao DL, Guo HJ, Li ZY. Solubility determination and correlation for 3-nitropyrazole in four binary solvents (water + methanol, ethanol, 1-propanol and acetone) from 283.15 K to 323.15 K. J Mol Liq 2021. [DOI: 10.1016/j.molliq.2021.117332] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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8
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Solubility and thermodynamic properties of an energetic intermediate in four binary solvents (water + n-butanol, n-pentanol, isobutanol and isoamyl alcohol). J Mol Liq 2021. [DOI: 10.1016/j.molliq.2021.117195] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
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9
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Yamashiro T, Yasujima T, Said HM, Yuasa H. pH-dependent pyridoxine transport by SLC19A2 and SLC19A3: Implications for absorption in acidic microclimates. J Biol Chem 2020; 295:16998-17008. [PMID: 33008889 PMCID: PMC7863892 DOI: 10.1074/jbc.ra120.013610] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2020] [Revised: 10/01/2020] [Indexed: 11/06/2022] Open
Abstract
SLC19A2 and SLC19A3, also known as thiamine transporters (THTR) 1 and 2, respectively, transport the positively charged thiamine (vitamin B1) into cells to enable its efficient utilization. SLC19A2 and SLC19A3 are also known to transport structurally unrelated cationic drugs, such as metformin, but whether this charge selectivity extends to other molecules, such as pyridoxine (vitamin B6), is unknown. We tested this possibility using Madin-Darby canine kidney II (MDCKII) cells and human embryonic kidney 293 (HEK293) cells for transfection experiments, and also using Caco-2 cells as human intestinal epithelial model cells. The stable expression of SLC19A2 and SLC19A3 in MDCKII cells (as well as their transient expression in HEK293 cells) led to a significant induction in pyridoxine uptake at pH 5.5 compared with control cells. The induced uptake was pH-dependent, favoring acidic conditions over neutral to basic conditions, and protonophore-sensitive. It was saturable as a function of pyridoxine concentration, with an apparent Km of 37.8 and 18.5 μm, for SLC19A2 and SLC19A3, respectively, and inhibited by the pyridoxine analogs pyridoxal and pyridoxamine as well as thiamine. We also found that silencing the endogenous SLC19A3, but not SLC19A2, of Caco-2 cells with gene-specific siRNAs lead to a significant reduction in carrier-mediated pyridoxine uptake. These results show that SLC19A2 and SLC19A3 are capable of recognizing/transporting pyridoxine, favoring acidic conditions for operation, and suggest a possible role for these transporters in pyridoxine transport mainly in tissues with an acidic environment like the small intestine, which has an acidic surface microclimate.
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Affiliation(s)
- Takahiro Yamashiro
- Department of Biopharmaceutics, Graduate School of Pharmaceutical Sciences, Nagoya City University, Nagoya, Japan
| | - Tomoya Yasujima
- Department of Biopharmaceutics, Graduate School of Pharmaceutical Sciences, Nagoya City University, Nagoya, Japan
| | - Hamid M Said
- Departments of Medicine and Physiology/Biophysics, University of California, Irvine, California, USA; Department of Veterans Affairs Medical Center, Long Beach, California, USA
| | - Hiroaki Yuasa
- Department of Biopharmaceutics, Graduate School of Pharmaceutical Sciences, Nagoya City University, Nagoya, Japan.
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Measurement and correlation of the solubility of 1-methyl-3,4,5-trinitropyrazole in twelve pure solvents at temperatures from 283.15 K to 323.15 K. J Mol Liq 2020. [DOI: 10.1016/j.molliq.2020.113895] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
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11
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Experimental study and thermodynamic modeling of a novel heat-resistant explosive in different mono solvents. J Mol Liq 2020. [DOI: 10.1016/j.molliq.2020.113056] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
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12
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Liamtsau V, Fan C, Liu G, McGoron AJ, Cai Y. Speciation of thioarsenicals through application of coffee ring effect on gold nanofilm and surface-enhanced Raman spectroscopy. Anal Chim Acta 2020; 1106:88-95. [PMID: 32145859 DOI: 10.1016/j.aca.2020.01.042] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2019] [Revised: 01/15/2020] [Accepted: 01/18/2020] [Indexed: 10/25/2022]
Abstract
Thioarsenicals, such as dimethylmonothioarsinic acid (DMMTAV) and dimethyldithioarsinic acid (DMDTAV), have been increasingly discovered as important arsenic metabolites, yet analysis of these unstable arsenic species remains a challenging task. A method based on surface-enhanced Raman spectroscopy (SERS) detection in combination with the coffee ringeffect for separation is expected to be particularly useful for analysis of thioarsenicals, thanks to minimal sample pretreatment and unique fingerprint Raman identification. Such a method would offer an alternative approach that overcomes limitations of conventional arsenic speciation techniques based on high performance liquid chromatography separation and mass spectrometry detection. A novel analytical method based on combination of the coffee ringeffect and SERS was developed for the speciation of thiolated arsenicals. A gold nanofilm (AuNF) was employed not only as a SERS substrate, but also as a platform for the separation of thioarsenicals. Once a drop of the thioarsenicals solution was placed onto the AuNF and evaporation of the solvent and the ring stamp formation onto AuNF began, the SERS signal intensity substantially increased from center to edge regions of the evaporated droplet due to the presence of the coffee ring effect. Through calculating the pKa's of DMMTAV and DMDTAV and accordingly manipulating the chemical environment, separation of these thioarsenicals was realized as they travelled different distances during the development of the coffee ring. The migration distances of individual species were influenced by a radial outward flow of a solute, the thioarsenicals-AuNF interactions and a thermally induced Marangoni flow. The separation of DMMTAV (center) and DMDTAV (edge) on the coffee ring, in combination with fingerprint SERS spectra, enables the identification of these thioarsenicals by this AuNF-based coffee ring effect-SERS method.
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Affiliation(s)
- Valery Liamtsau
- Department of Chemistry and Biochemistry, Florida International University, Miami, 11200 SW 8th ST, Miami, FL, 33199, USA
| | - Changjun Fan
- Department of Chemistry and Biochemistry, Florida International University, Miami, 11200 SW 8th ST, Miami, FL, 33199, USA
| | - Guangliang Liu
- Department of Chemistry and Biochemistry, Florida International University, Miami, 11200 SW 8th ST, Miami, FL, 33199, USA
| | - Anthony J McGoron
- Biomedical Engineering Department, Florida International University, 10555 West Flagler Street, EC 2442, Miami, FL, 33174, USA
| | - Yong Cai
- Department of Chemistry and Biochemistry, Florida International University, Miami, 11200 SW 8th ST, Miami, FL, 33199, USA; Southwest Environmental Research Center, Florida International University, 11200 SW 8th ST, Miami, FL, 33199, USA.
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13
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Chen YL, Kong X, Xie Y, Hider RC. The interaction of pyridoxal isonicotinoyl hydrazone (PIH) and salicylaldehyde isonicotinoyl hydrazone (SIH) with iron. J Inorg Biochem 2017; 180:194-203. [PMID: 29329026 DOI: 10.1016/j.jinorgbio.2017.12.007] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2017] [Revised: 12/06/2017] [Accepted: 12/10/2017] [Indexed: 01/23/2023]
Abstract
The interaction of pyridoxal isonicotinoyl hydrazone (PIH) and salicylaldehyde isonicotinoyl hydrazone (SIH), two important biologically active chelators, with iron has been investigated by spectrophotometric methods. High iron(III) affinity constants were determined for PIH, logβ2=37.0 and SIH, logβ2=37.6. The associated redox potentials of the iron complexes were determined using cyclic voltammetry at pH7.4 as +130mV (vs normal hydrogen electrode, NHE) for PIH and +136mV(vs NHE) for SIH. These redox potentials are much higher than those corresponding to iron chelators in clinical use, namely deferiprone, -620mV; desferasirox, -600mV and desferrioxamine, -468mV. Although the positive redox potentials of SIH and PIH are similar to that of EDTA, namely +120mV, the iron complexes of these two hydrazone chelators, unlike the iron complex of EDTA, do not redox cycle in the presence of vitamin C. These properties render PIH and SIH as excellent scavengers of iron, under biological conditions. Both SIH and PIH scavenge mononuclear iron(II) and iron(III) rapidly. These fast kinetic properties of the hydrazone-based chelators provide a ready explanation for the adoption of SIH in fluorescence-based methods for the quantification of cytosolic iron(II).
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Affiliation(s)
- Yu-Lin Chen
- Institute of Pharmaceutical Sciences, King's College London, 150 Stamford Street London SE1 9NH, UK
| | - Xiaole Kong
- Institute of Pharmaceutical Sciences, King's College London, 150 Stamford Street London SE1 9NH, UK
| | - Yuanyuan Xie
- Key Laboratory for Green Pharmaceutical Technologies and Related Equipment of Ministry of Education, Zhejiang University of Technology, PR China
| | - Robert C Hider
- Institute of Pharmaceutical Sciences, King's College London, 150 Stamford Street London SE1 9NH, UK.
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14
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Guo HJ, Dang X, Yang F, Cao DL, Li YX, Hu WH, Jiang ZM, Li ZH, Li ZY, Zhang LW. Solubility and thermodynamic properties of a kind of explosives in four binary solvents. J Mol Liq 2017. [DOI: 10.1016/j.molliq.2017.09.097] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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15
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Cvetkovski A, Ferretti V, Bertolasi V. New pharmaceutical salts containing pyridoxine. ACTA CRYSTALLOGRAPHICA SECTION C-STRUCTURAL CHEMISTRY 2017; 73:1064-1070. [PMID: 29206116 DOI: 10.1107/s2053229617015765] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/27/2017] [Accepted: 10/30/2017] [Indexed: 02/08/2023]
Abstract
Two mixed crystals were obtained by crystallizing the active pharmaceutical ingredient pyridoxine [systematic name: 4,5-bis(hydroxymethyl)-2-methylpyridin-3-ol, PN] with (E)-3-(4-hydroxy-3-methoxyphenyl)prop-2-enoic acid (ferulic acid) and 4-hydroxy-3,5-dimethoxybenzoic acid (syringic acid). PN and the coformers crystallize in the form of pharmaceutical salts in a 1:1 stoichiometric ratio, namely 3-hydroxy-4,5-bis(hydroxymethyl)-2-methylpyridin-1-ium (E)-3-(4-hydroxy-3-methoxyphenyl)prop-2-enoate, C8H12NO3+·C9H9O5-, and 3-hydroxy-4,5-bis(hydroxymethyl)-2-methylpyridin-1-ium 4-hydroxy-3,5-dimethoxybenzoate monohydrate, C8H12NO3+·C10H11O5-·H2O, the proton exchange between PN and the acidic partner being supported by the differences of the pKa values of the two components and by the C-O bond lengths of the carboxylate groups. Besides complex hydrogen-bonding networks, π-π interactions between aromatic moieties have been found to be important for the packing architecture in both crystals. Hirshfeld surface analysis was used to explore the intermolecular interactions in detail and compare them with the interactions found in similar pyridoxine/carboxylic acid salts.
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Affiliation(s)
- Aleksandar Cvetkovski
- Faculty of Medical Sciences, University Goce Delcev, Krste Misirkov bb, 2000 PO 201, Štip, The Former Yugoslav Republic of Macedonia
| | - Valeria Ferretti
- Department of Chemical and Pharmaceutical Sciences, University of Ferrara, via Fossato di Mortara 17, Ferrara I-44121, Italy
| | - Valerio Bertolasi
- Department of Chemical and Pharmaceutical Sciences, University of Ferrara, via Fossato di Mortara 17, Ferrara I-44121, Italy
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16
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Low Field NMR Determination of pKa Values for Hydrophilic Drugs for Students in Medicinal Chemistry. MAGNETOCHEMISTRY 2017. [DOI: 10.3390/magnetochemistry3030029] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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17
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Bhojane P, Duff MR, Bafna K, Rimmer GP, Agarwal PK, Howell EE. Aspects of Weak Interactions between Folate and Glycine Betaine. Biochemistry 2016; 55:6282-6294. [PMID: 27768285 PMCID: PMC5198541 DOI: 10.1021/acs.biochem.6b00873] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2016] [Revised: 10/19/2016] [Indexed: 01/22/2023]
Abstract
Folate, or vitamin B9, is an important compound in one-carbon metabolism. Previous studies have found weaker binding of dihydrofolate to dihydrofolate reductase in the presence of osmolytes. In other words, osmolytes are more difficult to remove from the dihydrofolate solvation shell than water; this shifts the equilibrium toward the free ligand and protein species. This study uses vapor-pressure osmometry to explore the interaction of folate with the model osmolyte, glycine betaine. This method yields a preferential interaction potential (μ23/RT value). This value is concentration-dependent as folate dimerizes. The μ23/RT value also tracks the deprotonation of folate's N3-O4 keto-enol group, yielding a pKa of 8.1. To determine which folate atoms interact most strongly with betaine, the interaction of heterocyclic aromatic compounds (as well as other small molecules) with betaine was monitored. Using an accessible surface area approach coupled with osmometry measurements, deconvolution of the μ23/RT values into α values for atom types was achieved. This allows prediction of μ23/RT values for larger molecules such as folate. Molecular dynamics simulations of folate show a variety of structures from extended to L-shaped. These conformers possess μ23/RT values from -0.18 to 0.09 m-1, where a negative value indicates a preference for solvation by betaine and a positive value indicates a preference for water. This range of values is consistent with values observed in osmometry and solubility experiments. As the average predicted folate μ23/RT value is near zero, this indicates folate interacts almost equally well with betaine and water. Specifically, the glutamate tail prefers to interact with water, while the aromatic rings prefer betaine. In general, the more protonated species in our small molecule survey interact better with betaine as they provide a source of hydrogens (betaine is not a hydrogen bond donor). Upon deprotonation of the small molecule, the preference swings toward water interaction because of its hydrogen bond donating capacities.
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Affiliation(s)
- Purva
P. Bhojane
- Department
of Biochemistry and Cellular and Molecular Biology, University of Tennessee, Knoxville, Tennessee 37996-0840, United States
| | - Michael R. Duff
- Department
of Biochemistry and Cellular and Molecular Biology, University of Tennessee, Knoxville, Tennessee 37996-0840, United States
| | - Khushboo Bafna
- Genome
Science and Technology Program, University
of Tennessee, Knoxville, Tennessee 37996-0840, United States
| | - Gabriella P. Rimmer
- Department
of Biochemistry and Cellular and Molecular Biology, University of Tennessee, Knoxville, Tennessee 37996-0840, United States
| | - Pratul K. Agarwal
- Department
of Biochemistry and Cellular and Molecular Biology, University of Tennessee, Knoxville, Tennessee 37996-0840, United States
- Genome
Science and Technology Program, University
of Tennessee, Knoxville, Tennessee 37996-0840, United States
- Computer
Science and Mathematics Division, Oak Ridge
National Laboratory, Oak Ridge, Tennessee 37831, United States
| | - Elizabeth E. Howell
- Department
of Biochemistry and Cellular and Molecular Biology, University of Tennessee, Knoxville, Tennessee 37996-0840, United States
- Genome
Science and Technology Program, University
of Tennessee, Knoxville, Tennessee 37996-0840, United States
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Kiani F, Abbaszadeh M, Pousti M, Koohyar F. Theoretically nanoscale study on ionization of muscimol nano drug in aqueous solution. BRAZ J PHARM SCI 2015. [DOI: 10.1590/s1984-82502015000100021] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
In the present work, acid dissociation constant (pKa) values of muscimol derivatives were calculated using the Density Functional Theory (DFT) method. In this regard, free energy values of neutral, protonated and deprotonated species of muscimol were calculated in water at the B3LYP/6-31G(d) basis sets. The hydrogen bond formation of all species had been analyzed using the Tomasi's method. It was revealed that the theoretically calculated pKa values were in a good agreement with the existing experimental pKa values, which were determined from capillary electrophoresis, potentiometric titration and UV-visible spectrophotometric measurements.
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