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Durrant A, Peron JMR, Langat MK, Robertson C, Le Gresley A. Modified PSYCHE NMR - The possibility for the direct semi-quantitation of components in mixtures. Talanta 2024; 268:125332. [PMID: 37890372 DOI: 10.1016/j.talanta.2023.125332] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2023] [Revised: 10/18/2023] [Accepted: 10/21/2023] [Indexed: 10/29/2023]
Abstract
A series of commonly occurring biologically relevant compounds were analysed using internally referenced PSYCHE NMR and the accuracy/precision compared with that achieved using conventional qNMR. The effect of chemical shift, coupling constants, swept frequency pulse angle, excitation sculpting and the impact of signal overlap in mixtures was evaluated in terms of statistically significant variation between the two techniques. It is shown that suitably optimised PSYCHE NMR represents a potentially reliable method for the semi-quantitation of mixtures of compounds, whose spectroscopic signals overlap in conventional qNMR analysis and hence cannot be accurately quantified with that technique. This is of particular relevance for complex mixtures of natural products. Of particular note is the effect of the excitation sculpting block introduced to supress baseline artefacts.
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Affiliation(s)
- Arija Durrant
- School of Life Sciences Pharmacy and Chemistry, HSSCE Faculty, Kingston University, KT1 2EE, UK
| | - Jean-Marie R Peron
- School of Life Sciences Pharmacy and Chemistry, HSSCE Faculty, Kingston University, KT1 2EE, UK
| | | | - Cameron Robertson
- School of Life Sciences Pharmacy and Chemistry, HSSCE Faculty, Kingston University, KT1 2EE, UK
| | - Adam Le Gresley
- School of Life Sciences Pharmacy and Chemistry, HSSCE Faculty, Kingston University, KT1 2EE, UK.
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2
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Sainju D, Lucas R, Le Gresley A. Evaluation of nuclear magnetic resonance spectroscopy for characterisation and quantitation of water-soluble polymers in river water. Water Res 2023; 245:120650. [PMID: 37742403 DOI: 10.1016/j.watres.2023.120650] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/14/2023] [Revised: 08/14/2023] [Accepted: 09/18/2023] [Indexed: 09/26/2023]
Abstract
Water-soluble polymers (WSPs) are commonly used in industrial, commercial, agricultural and pharmaceutical products and their molecular weights and concentrations vary considerably. Methods commonly used in the analysis of WSPs are often for pure products or formulations with only a few other high MW constituents. These methods, like size exclusion chromatography (SEC) or Gel Permeation Chromatography coupled with Mass Spectrometry (MS) can be frustrated by the impact of the necessary separation steps prior to identification and the limitations of MS when identifying and quantifying polymers. To that end, the employment of a Nuclear Magnetic Resonance (NMR) method to identify, characterize and quantify WSPs in the real-world is reported for the first time. Samples were taken from fourteen UK inland river sites, concentrated via air-drying, freeze-drying or vacuum-drying and analyzed using 1D 1H NMR and 2D 1H Diffusion Ordered Spectroscopy (DOSY) NMR analysis. Seven of the river sites showed the presence of polyethylene glycol (PEG) with a range of molecular weights, evidencing the application of these techniques in analysis of WSPs. Soil percolation models evidenced the proof of principle that these techniques can also be used for the detection of polyacrylamide (PAM) and polyacrylic acid (PAA). This work should better enable the evaluation of the biological impact of WSPs on aquatic organisms in future studies.
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Affiliation(s)
- Drishna Sainju
- Department of Chemistry and Pharmaceutical Sciences, HSSCE Faculty, Kingston University, Kingston-upon-Thames, Surrey KT1 2EE, UK
| | - Robert Lucas
- Consumer Healthcare, Haleon PLC, Weybridge, Surrey, UK
| | - Adam Le Gresley
- Department of Chemistry and Pharmaceutical Sciences, HSSCE Faculty, Kingston University, Kingston-upon-Thames, Surrey KT1 2EE, UK.
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3
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Fudger A, Cakir OM, Khan Y, Sinclair A, Le Gresley A. Chemical synthesis of a library of natural product-like derivatives based on pinnaic acid and initial evaluation of their anti-cancer activity. Org Biomol Chem 2022; 20:9408-9421. [PMID: 36398757 DOI: 10.1039/d2ob01626e] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Halichlorine and pinnaic acid have been shown previously to be potent inhibitors of the inflammatory enzymes cPLA2 and VCAM-1 and have also demonstrated some anti-cancer activity. They possess an almost identical azaspirocyclic core consisting of a unique 3-dimensional geometry with four stereocentres, making them compounds of interest for further study to reveal any bioactivity not yet discovered. The azaspirocyclic core was synthesised from an established protocol, from which a small library of novel analogues were synthesised and tested for activity against two cancer cell lines, HeLa and CaCo-2, along with the non-cancerous cell line HaCaT. Eleven compounds were found to be selective for CaCo-2 cells.
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Affiliation(s)
- Alex Fudger
- School of Life Sciences, Pharmacy and Chemistry, HSSCE Faculty, Kingston University, Kingston upon Thames, KT1 2EE, UK.
| | - Okan M Cakir
- School of Life Sciences, Pharmacy and Chemistry, HSSCE Faculty, Kingston University, Kingston upon Thames, KT1 2EE, UK.
| | - Yousaf Khan
- School of Life Sciences, Pharmacy and Chemistry, HSSCE Faculty, Kingston University, Kingston upon Thames, KT1 2EE, UK.
| | - Alex Sinclair
- School of Life Sciences, Pharmacy and Chemistry, HSSCE Faculty, Kingston University, Kingston upon Thames, KT1 2EE, UK.
| | - Adam Le Gresley
- School of Life Sciences, Pharmacy and Chemistry, HSSCE Faculty, Kingston University, Kingston upon Thames, KT1 2EE, UK.
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4
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Ampem G, Le Gresley A, Grootveld M, Naughton DP. Nuclear Magnetic Resonance Spectroscopic Analysis of the Evolution of Peroxidation Products Arising from Culinary Oils Exposed to Thermal Oxidation: An Investigation Employing 1H and 1H-1H COSY and TOCSY Techniques. Foods 2022; 11:foods11131864. [PMID: 35804680 PMCID: PMC9265948 DOI: 10.3390/foods11131864] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2022] [Revised: 06/15/2022] [Accepted: 06/20/2022] [Indexed: 02/05/2023] Open
Abstract
Scientific warnings on the deleterious health effects exerted by dietary lipid oxidation products (LOPs) present in thermally stressed culinary oils have, to date, not received adequate attention given that there has been an increase in the use and consumption of such oil products in everyday life. In this study, high-resolution 1H nuclear magnetic resonance (NMR) analysis was used to characterize and map chemical modifications to fatty acid (FA) acyl groups and the evolution of LOPs in saturated fatty acid (SFA)-rich ghee, monounsaturated fatty acid (MUFA)-rich groundnut, extra virgin olive, and macadamia oils, along with polyunsaturated fatty acid (PUFA)-rich sesame, corn and walnut oils, which were all thermally stressed at 180 °C, continuously and discontinuously for 300 and 480 min, respectively. Results acquired revealed that PUFA-rich culinary oils were more susceptible to thermo-oxidative stress than the others tested, as expected. However, ghee and macadamia oil both generated only low levels of toxic LOPs, and these results demonstrated a striking similarity. Furthermore, at the 120 min thermo-oxidation time-point, the discontinuous thermo-oxidation episodes produced higher concentrations of aldehydic LOPs than those produced during continuous thermo-oxidation sessions for the same duration. On completion of the thermo-oxidation period, a higher level of triacylglycerol chain degradation, and hence, higher concentrations of aldehydes, were registered in culinary oils thermally stressed continuously over those found in discontinuous thermo-oxidized oils. These findings may be crucial in setting targets and developing scientific methods for the suppression of LOPs in thermo-oxidized oils.
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Affiliation(s)
- Gilbert Ampem
- Department of Chemistry and Pharmaceutical Sciences, SEC Faculty, Kingston University, Kingston-upon-Thames, Surrey KT1 2EE, UK; (G.A.); (D.P.N.)
| | - Adam Le Gresley
- Department of Chemistry and Pharmaceutical Sciences, SEC Faculty, Kingston University, Kingston-upon-Thames, Surrey KT1 2EE, UK; (G.A.); (D.P.N.)
- Correspondence: ; Tel.: +44-(0)20-8417-7432
| | - Martin Grootveld
- Leicester School of Pharmacy, De Montfort University, Leicester LE1 9BH, UK;
| | - Declan P. Naughton
- Department of Chemistry and Pharmaceutical Sciences, SEC Faculty, Kingston University, Kingston-upon-Thames, Surrey KT1 2EE, UK; (G.A.); (D.P.N.)
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5
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Zecchini M, Lucas RA, Robertson C, Coban T, Thatti R, Le Gresley A. Investigation of the Formation of Squalene Oligomers Exposed to Ultraviolet Light and Changes in the Exposed Squalene as a Potential Skin Model. Molecules 2022; 27:molecules27113481. [PMID: 35684418 PMCID: PMC9182105 DOI: 10.3390/molecules27113481] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2022] [Revised: 05/25/2022] [Accepted: 05/26/2022] [Indexed: 02/05/2023] Open
Abstract
UV-induced oligomerisation of squalene was undertaken to indicate the potential for squalene-containing biological systems to exhibit rheology changes. DOSY NMR enabled the determination of the molecular weight (MW) range using Stokes–Einstein Gierer–Wirtz Estimation (SEGWE Calculator, University of Manchester). This approach was validated by Atmospheric Solids Analysis Probe Time of Flight Mass Spectrometry (ASAP TOF MS). To demonstrate the principle, both benzoyl peroxide and AIBN were used, separately, to initiate rapid, radical oligomerisation. Subsequent experiments in the absence of initiators compared the influence of UV wavelength and time on the resulting oligomer formation. To further model a relevant biological implication of this potentially chaotic UV oligomerisation, both saturated and unsaturated free fatty acids were added to squalene and exposed to UV at 285 nm and 300 nm to determine if cross oligomerisation could be observed. This representation of sebum evidenced the formation of a distribution of higher MW oligomers. Internal viscosity was normalised using the DMSO solvent, but to confirm that changes in rheology did not affect diffusion, a final experiment where fresh squalene was added to our oligomer mixture, representative of sebum, showed that unchanged squalene possessed the anticipated monomeric diffusion coefficient and hence MW. This work suggests, at least qualitatively, that UV-induced squalene oligomerisation can occur over time and that this may have a role in the behaviour of squalene on the skin.
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Affiliation(s)
- Matteo Zecchini
- Life Sciences, Pharmacy and Chemistry, SEC Faculty, Kingston University, Kingston-upon-Thames KT1 2EE, UK; (M.Z.); (C.R.); (T.C.); (R.T.)
| | - Robert A. Lucas
- GlaxoSmithKline Consumer Healthcare, Weybridge KT13 0DE, UK;
| | - Cameron Robertson
- Life Sciences, Pharmacy and Chemistry, SEC Faculty, Kingston University, Kingston-upon-Thames KT1 2EE, UK; (M.Z.); (C.R.); (T.C.); (R.T.)
| | - Tomris Coban
- Life Sciences, Pharmacy and Chemistry, SEC Faculty, Kingston University, Kingston-upon-Thames KT1 2EE, UK; (M.Z.); (C.R.); (T.C.); (R.T.)
| | - Ravtej Thatti
- Life Sciences, Pharmacy and Chemistry, SEC Faculty, Kingston University, Kingston-upon-Thames KT1 2EE, UK; (M.Z.); (C.R.); (T.C.); (R.T.)
| | - Adam Le Gresley
- Life Sciences, Pharmacy and Chemistry, SEC Faculty, Kingston University, Kingston-upon-Thames KT1 2EE, UK; (M.Z.); (C.R.); (T.C.); (R.T.)
- Correspondence: ; Tel.: +44-(0)208-417-7432
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6
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Grootveld M, Addis PB, Le Gresley A. Editorial: Dietary Lipid Oxidation and Fried Food Toxicology. Front Nutr 2022; 9:858063. [PMID: 35308283 PMCID: PMC8931324 DOI: 10.3389/fnut.2022.858063] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2022] [Accepted: 02/04/2022] [Indexed: 11/28/2022] Open
Affiliation(s)
- Martin Grootveld
- Leicester School of Pharmacy, De Montfort University, Leicester, United Kingdom
- *Correspondence: Martin Grootveld
| | - Paul B. Addis
- Department of Food Science and Nutrition, Saint Paul, MN, United States
| | - Adam Le Gresley
- School of Life Sciences, Pharmacy and Chemistry, Kingston University, Kingston upon Thames, United Kingdom
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7
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Robertson C, Raj N, Lucas R, Coban T, Gresley AL. A proof-of-concept study utilising 2D NMR spectrometry for in situ characterisation and quantitation of key biomarkers and actives in tape stripped ex vivo human skin. Talanta 2022; 237:122980. [PMID: 34736701 DOI: 10.1016/j.talanta.2021.122980] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2021] [Revised: 10/11/2021] [Accepted: 10/17/2021] [Indexed: 11/17/2022]
Abstract
The development of a semi-automated and rapid analytical technique for dermatological analysis has become a key aim of many medical and commercial entities through greater awareness of people to skin health and its importance in the 21st century. We present a proof-of-concept methodology demonstrating the use of validated non-destructive, in-situ (Nuclear Magnetic Resonance Spectroscopy) NMR techniques for characterisation and quantitation of (Natural Moisturising Factor) NMF compounds and actives from topical formulations. This quantitation is crucial for appropriate diagnosis of atopic dermatitis severity due to its association with reduced NMF abundance. This study is the first to combine diffusion NMR, semi-automated quantitation and ex-vivo skin samples to measure NMF and permeation of actives. We have shown that diffusion NMR allows for resolution between formulation components through determination of self-diffusion coefficients. We also demonstrate how the metabolomics software chenomxtm can be used to identify and quantitate individual NMF components. We show comparable results to previous literature on NMF layers in the skin, alongside reinforcing findings on permeation enhancers and heat effects on transdermal delivery of actives and formulation components. The presented methodology has shown great potential as an effective non-destructive, fast and versatile technique for dermatological analysis of physiology and actives, with future hardware and software developments in NMR making the future of dermatological analysis via NMR very promising.
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Affiliation(s)
- Cameron Robertson
- Department of Chemical and Pharmaceutical Sciences, Faculty of SEC, Kingston University, Kingston-upon-Thames, Surrey, KT1 2EE, UK.
| | - Nidhin Raj
- GlaxoSmithKline Consumer Healthcare, Weybridge, UK
| | - Robert Lucas
- GlaxoSmithKline Consumer Healthcare, Weybridge, UK
| | - Tomris Coban
- Department of Chemical and Pharmaceutical Sciences, Faculty of SEC, Kingston University, Kingston-upon-Thames, Surrey, KT1 2EE, UK
| | - Adam Le Gresley
- Department of Chemical and Pharmaceutical Sciences, Faculty of SEC, Kingston University, Kingston-upon-Thames, Surrey, KT1 2EE, UK
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8
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Ampem G, Gresley AL, Grootveld M, De Mars S, Naughton DP. The impact of partial oil substitution and trace metal ions on the evolution of peroxidation products in thermally stressed culinary oils. Food Chem 2021; 375:131823. [PMID: 34920305 DOI: 10.1016/j.foodchem.2021.131823] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2021] [Revised: 11/24/2021] [Accepted: 12/05/2021] [Indexed: 02/01/2023]
Abstract
Suppressing toxic aldehydic lipid oxidation product (LOP) generation in culinary oils is now considered vital, since the deleterious effects arising from their ingestion are implicated in a wide range of disease conditions. Partial substitution involves the replenishment of thermally-stressed culinary oils with corresponding unheated ones. This technique was tested by employing 10%, 25%, 50%, and 75% (v/v) partial substitutions of coconut, olive, rapeseed, and sunflower oils at 180℃ for a 300 min continuous thermo-oxidation duration. Oil samples were analysed by proton nuclear magnetic resonance (1H NMR) spectroscopy. Trace metal levels, including oxidation-reduction (redox)-active metal ions credited with enhancing cooking oil oxidation were also analysed using inductively coupled plasma-optical emission spectroscopy (ICP-OES). As expected, the degree of oil unsaturation, and the % partial substitutions significantly influenced their susceptibility to thermo-oxidation. In view of the very low polyunsaturated fatty acid (PUFA) and monounsaturated fatty acid (MUFA) contents of coconut oil, both the class and concentrations of evolved LOPs were found to be least affected by this partial substitution process. Aldehydic LOPs were greatly suppressed in partially-substituted rapeseed oil. The % suppression activity of LOPs evaluated for the partially substituted oils were generally high making partial oil substitutions an effective chemical-free method in suppressing LOPs at both industrial and commercial levels. In general, the % partial oil substitutions were directly related to the dilution effect observed for LOPs quantified in the oils. Furthermore, trace metal ion concentrations measured in the culinary oils did not influence the evolution of LOPs in the oils.
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Affiliation(s)
- Gilbert Ampem
- Department of Chemistry and Pharmaceutical Sciences, SEC Faculty, Kingston University, Kingston-upon-Thames, Surrey KT1 2EE, UK
| | - Adam Le Gresley
- Department of Chemistry and Pharmaceutical Sciences, SEC Faculty, Kingston University, Kingston-upon-Thames, Surrey KT1 2EE, UK.
| | - Martin Grootveld
- Health and Life Sciences, De Montfort University, Leicester LE1 9BH, UK
| | - Simon De Mars
- Department of Chemistry and Pharmaceutical Sciences, SEC Faculty, Kingston University, Kingston-upon-Thames, Surrey KT1 2EE, UK
| | - Declan P Naughton
- Department of Chemistry and Pharmaceutical Sciences, SEC Faculty, Kingston University, Kingston-upon-Thames, Surrey KT1 2EE, UK
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9
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Ampem G, Le Gresley A, Grootveld M, Naughton DP. The Role of Polydimethylsiloxane in Suppressing the Evolution of Lipid Oxidation Products in Thermo-Oxidised Sunflower Oil: Influence of Stirring Processes. Front Nutr 2021; 8:721736. [PMID: 34447780 PMCID: PMC8382684 DOI: 10.3389/fnut.2021.721736] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2021] [Accepted: 07/13/2021] [Indexed: 11/17/2022] Open
Abstract
Suppressing the evolution of lipid oxidation products (LOPs) in commercially available culinary oils is considered to represent a valuable health-promoting incentive since these agents have cytotoxic and genotoxic properties and have been implicated in the pathogenesis of several chronic disease states. One agent used to suppress LOPs formation is polydimethylsiloxane (PDMS). In this study, proton nuclear magnetic resonance (1H NMR) analysis was employed to evaluating the influence of increasing PDMS concentrations (6.25 × 10−7, 1.0 × 10−5, 0.025, 0.05, 0.1, 0.5, 1.0, 5.0, and 10.0 ppm) in either stirred or unstirred refined sunflower oil exposed to thermal stressing episodes continuously at 180°C for 300 min with no oil replenishment. Results acquired showed that the extent of blockage of LOPs generation was correlated with increasing concentrations of PDMS. The minimal level of added PDMS required to provide a statistically significant protective role for both stirred and unstirred culinary oils when exposed to high frying temperatures was only 6.25 × 10−7 ppm. Furthermore, stirring at 250 rpm was experimentally determined to reduce the functional role PDMS. This is vital in a real world setting since the boiling process of frying may ultimately reduce the LOPs suppression activity of PDMS.
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Affiliation(s)
- Gilbert Ampem
- Department of Chemistry and Pharmaceutical Sciences, Science, Engineering, and Computing Faculty, Kingston University, Kingston-upon-Thames, United Kingdom
| | - Adam Le Gresley
- Department of Chemistry and Pharmaceutical Sciences, Science, Engineering, and Computing Faculty, Kingston University, Kingston-upon-Thames, United Kingdom
| | - Martin Grootveld
- Health and Life Sciences, De Montfort University, Leicester, United Kingdom
| | - Declan P Naughton
- Department of Chemistry and Pharmaceutical Sciences, Science, Engineering, and Computing Faculty, Kingston University, Kingston-upon-Thames, United Kingdom
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10
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Long N, Le Gresley A, Wren SP. Thiazolidinediones: An In-Depth Study of Their Synthesis and Application to Medicinal Chemistry in the Treatment of Diabetes Mellitus. ChemMedChem 2021; 16:1716-1735. [PMID: 33844475 PMCID: PMC8251912 DOI: 10.1002/cmdc.202100177] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2021] [Indexed: 12/25/2022]
Abstract
2,4-Thiazolidinedione (TZD) is a privileged and highly utilised scaffold for the development of pharmaceutically active compounds. This sulfur-containing heterocycle is a versatile pharmacophore that confers a diverse range of pharmacological activities. TZD has been shown to exhibit biological action towards a vast range of targets interesting to medicinal chemists. In this review, we attempt to provide insight into both the historical conventional and the use of novel methodologies to synthesise the TZD core framework. Further to this, synthetic procedures utilised to substitute the TZD molecule at the activated methylene C5 and N3 position are reviewed. Finally, research into developing clinical agents, which act as modulators of peroxisome proliferator-activated receptors gamma (PPARγ), protein tyrosine phosphatase 1B (PTP1B) and aldose reductase 2 (ALR2), are discussed. These are the three most targeted receptors for the treatment of diabetes mellitus (DM).
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Affiliation(s)
- Nathan Long
- Department of Chemical & Pharmaceutical SciencesFaculty of ScienceEngineering & ComputingKingston University LondonPenrhyn RoadSurreyKT1 2EEUK
| | - Adam Le Gresley
- Department of Chemical & Pharmaceutical SciencesFaculty of ScienceEngineering & ComputingKingston University LondonPenrhyn RoadSurreyKT1 2EEUK
| | - Stephen P. Wren
- Department of Chemical & Pharmaceutical SciencesFaculty of ScienceEngineering & ComputingKingston University LondonPenrhyn RoadSurreyKT1 2EEUK
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11
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Dahabra L, Broadberry G, Le Gresley A, Najlah M, Khoder M. Sunscreens Containing Cyclodextrin Inclusion Complexes for Enhanced Efficiency: A Strategy for Skin Cancer Prevention. Molecules 2021; 26:1698. [PMID: 33803643 PMCID: PMC8003006 DOI: 10.3390/molecules26061698] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2021] [Revised: 03/09/2021] [Accepted: 03/16/2021] [Indexed: 11/19/2022] Open
Abstract
Unprotected exposure of skin to solar ultraviolet radiation (UVR) may damage the DNA of skin cells and can lead to skin cancer. Sunscreens are topical formulations used to protect skin against UVR. The active ingredients of sunscreens are UV filters that absorb, scatter, and/or reflect UVR. Preventing the formation of free radicals and repairing DNA damages, natural antioxidants are also added to sunscreens as a second fold of protection against UVR. Antioxidants can help stabilise these formulations during the manufacturing process and upon application on skin. However, UV filters and antioxidants are both susceptible to degradation upon exposure to sunlight and oxygen. Additionally, due to their poor water solubility, natural antioxidants are challenging to formulate and exhibit limited penetration and bioavailability in the site of action (i.e., deeper skin layers). Cyclodextrins (CDs) are cyclic oligosaccharides that are capable of forming inclusion complexes with poorly soluble drugs, such as antioxidants. In this review, we discuss the use of CDs inclusion complexes to enhance the aqueous solubility of antioxidants and chemical UV filters and provide a protective shield against degradative factors. The role of CDs in providing a controlled drug release profile from sunscreens is also discussed. Finally, incorporating CDs inclusion complexes into sunscreens has the potential to increase their efficiency and hence improve their skin cancer prevention.
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Affiliation(s)
- Layan Dahabra
- School of Life Sciences, Pharmacy and Chemistry, SEC Faculty, Kingston University, Kingston-upon-Thames KT1 2EE, UK; (L.D.); (G.B.); (A.L.G.)
| | - Grace Broadberry
- School of Life Sciences, Pharmacy and Chemistry, SEC Faculty, Kingston University, Kingston-upon-Thames KT1 2EE, UK; (L.D.); (G.B.); (A.L.G.)
| | - Adam Le Gresley
- School of Life Sciences, Pharmacy and Chemistry, SEC Faculty, Kingston University, Kingston-upon-Thames KT1 2EE, UK; (L.D.); (G.B.); (A.L.G.)
| | - Mohammad Najlah
- Pharmaceutical Research Group, School of Allied Health, Faculty of Health, Education, Medicine and Social Care, Anglia Ruskin University, Bishops Hall Lane, Chelmsford CM1 1SQ, UK;
| | - Mouhamad Khoder
- School of Life Sciences, Pharmacy and Chemistry, SEC Faculty, Kingston University, Kingston-upon-Thames KT1 2EE, UK; (L.D.); (G.B.); (A.L.G.)
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12
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Awadh AA, Le Gresley A, Forster-Wilkins G, Kelly AF, Fielder MD. Determination of metabolic activity in planktonic and biofilm cells of Mycoplasma fermentans and Mycoplasma pneumoniae by nuclear magnetic resonance. Sci Rep 2021; 11:5650. [PMID: 33707544 PMCID: PMC7952918 DOI: 10.1038/s41598-021-84326-2] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2020] [Accepted: 02/03/2021] [Indexed: 01/31/2023] Open
Abstract
Mycoplasmas are fastidious microorganisms, typically characterised by their restricted metabolism and minimalist genome. Although there is reported evidence that some mycoplasmas can develop biofilms little is known about any differences in metabolism in these organisms between the growth states. A systematic metabolomics approach may help clarify differences associated between planktonic and biofilm associated mycoplasmas. In the current study, the metabolomics of two different mycoplasmas of clinical importance (Mycoplasma pneumoniae and Mycoplasma fermentans) were examined using a novel approach involving nuclear magnetic resonance spectroscopy and principle component analysis. Characterisation of metabolic changes was facilitated through the generation of high-density metabolite data and diffusion-ordered spectroscopy that provided the size and structural information of the molecules under examination. This enabled the discrimination between biofilms and planktonic states for the metabolomic profiles of both organisms. This work identified clear biofilm/planktonic differences in metabolite composition for both clinical mycoplasmas and the outcomes serve to establish a baseline understanding of the changes in metabolism observed in these pathogens in their different growth states. This may offer insight into how these organisms are capable of exploiting and persisting in different niches and so facilitate their survival in the clinical setting.
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Affiliation(s)
- Ammar A. Awadh
- grid.15538.3a0000 0001 0536 3773School of Life Sciences, Pharmacy and Chemistry, SEC Faculty, Kingston University London, Kingston Upon Thames, UK
| | - Adam Le Gresley
- grid.15538.3a0000 0001 0536 3773School of Life Sciences, Pharmacy and Chemistry, SEC Faculty, Kingston University London, Kingston Upon Thames, UK
| | - Gary Forster-Wilkins
- grid.15538.3a0000 0001 0536 3773School of Life Sciences, Pharmacy and Chemistry, SEC Faculty, Kingston University London, Kingston Upon Thames, UK
| | - Alison F. Kelly
- grid.15538.3a0000 0001 0536 3773School of Life Sciences, Pharmacy and Chemistry, SEC Faculty, Kingston University London, Kingston Upon Thames, UK
| | - Mark D. Fielder
- grid.15538.3a0000 0001 0536 3773School of Life Sciences, Pharmacy and Chemistry, SEC Faculty, Kingston University London, Kingston Upon Thames, UK
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Le Gresley A, Ampem G, De Mars S, Grootveld M, Naughton DP. "Real-World" Evaluation of Lipid Oxidation Products and Trace Metals in French Fries From Two Chain Fast-Food Restaurants. Front Nutr 2021; 8:620952. [PMID: 33614697 PMCID: PMC7892784 DOI: 10.3389/fnut.2021.620952] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2020] [Accepted: 01/12/2021] [Indexed: 01/19/2023] Open
Abstract
Differences in lipid oxidation products (LOPs) and trace metal concentrations of French fry samples found between two global chain fast-food restaurants in the UK were investigated using high-resolution proton nuclear magnetic resonance (1H NMR) and inductively coupled plasma-optical emission spectrometry (ICP-OES) analyses, respectively, of extracts derived therefrom. Over the course of 3 days and 3 different diurnal time periods, samples of French fries (FFs) were analyzed, and comparisons of two different oil extraction methods were undertaken for the two restaurants involved. The magnitude of concentrations of LOPs extracted from FFs is discussed. Significant differences between 6/7 aldehyde classifications, and aluminum, manganese, vanadium, lead, iron, copper and nickel levels between samples from the two restaurants are also reported. Redox-active transition and further trace metal concentrations inversely correlated with FF oil sample LOP contents; this suggested an antioxidant rather than a pro-oxidant role for them.
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Affiliation(s)
- Adam Le Gresley
- Department of Chemistry and Pharmaceutical Sciences, Kingston University, Kingston-upon-Thames, United Kingdom
| | - Gilbert Ampem
- Department of Chemistry and Pharmaceutical Sciences, Kingston University, Kingston-upon-Thames, United Kingdom
| | - Simon De Mars
- Department of Chemistry and Pharmaceutical Sciences, Kingston University, Kingston-upon-Thames, United Kingdom
| | - Martin Grootveld
- Leicester School of Pharmacy, De Montfort University, Leicester, United Kingdom
| | - Declan P. Naughton
- Department of Chemistry and Pharmaceutical Sciences, Kingston University, Kingston-upon-Thames, United Kingdom
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Malik S, Sinclair A, Ryan A, Le Gresley A. Synthesis and Initial Evaluation of a Novel Fluorophore for Selective FMDV 3C Protease Detection. Molecules 2020; 25:E3599. [PMID: 32784761 PMCID: PMC7465021 DOI: 10.3390/molecules25163599] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2020] [Revised: 07/28/2020] [Accepted: 08/04/2020] [Indexed: 11/16/2022] Open
Abstract
The development and evaluation of a Boc-AL(Boc)Q(Trt)-AMC fluorophore to detect 3C Protease, produced by Foot and Mouth Disease Virus (FMDV) is reported, with a view to a potential use as a rapid screen for FMDV infected livestock The peptide-linked conjugate fluorophore is evaluated in vitro for sensitivity, specificity, stability and rapidity and shows statistically significant increases in fluorescence when exposed to physiologically relevant concentrations of 3C Protease and selectivity when compared with other common proteases likely to be located, typically in the absence of FMDV. The stability of deprotected Boc-AL(Boc)Q(Trt)-AMC is reported as a limitation of this probe.
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Affiliation(s)
| | | | | | - Adam Le Gresley
- Chemical and Pharmaceutical Sciences, SEC Faculty, Kingston University, Kingston-upon-Thames, London KT1 2EE, UK; (S.M.); (A.S.); (A.R.)
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Percival BC, Wann A, Zbasnik R, Schlegel V, Edgar M, Zhang J, Ampem G, Wilson P, Le Gresley A, Naughton D, Grootveld M. Evaluations of the Peroxidative Susceptibilities of Cod Liver Oils by a 1H NMR Analysis Strategy: Peroxidative Resistivity of a Natural Collagenous and Biogenic Amine-Rich Fermented Product. Nutrients 2020; 12:E753. [PMID: 32178350 PMCID: PMC7146420 DOI: 10.3390/nu12030753] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2020] [Revised: 03/03/2020] [Accepted: 03/06/2020] [Indexed: 11/20/2022] Open
Abstract
High-resolution 1H nuclear magnetic resonance (NMR) analysis was employed to molecularly screen the lipid, lipid oxidation product (LOP), and antioxidant compositions of four natural (unrefined) cod liver oil (CLO) products. Products 1-3 were non-fermented CLOs, whilst Product 4 was isolated from pre-fermented cod livers. Supporting analytical data that were acquired included biogenic amine, flavanone, tannin, phenolic antioxidant, α-tocopherol, and oxygen radical absorbance capacity (ORAC) determinations by recommended HPLC, LC/MS/MS, or spectrophotometric methods. SDS-PAGE, HPLC, and 1H NMR analyses investigated and determined collagenous antioxidants and their molecular mass ranges. 1H NMR analysis of aldehydic LOPs was employed to explore the susceptibilities/resistivities of each CLO product to peroxidation that is induced by thermal stressing episodes (TSEs) at 180°C, or following prolonged (42 day) storage episodes at 4 and 23 °C. Product 4 displayed extremely high ORAC values, which were much greater than those of Products 1-3, and that were predominantly ascribable to significant levels of peroxidation-blocking and/or aldehyde-consuming collagenous polypeptides/peptides and ammoniacal agents therein. Significantly lower levels of toxic aldehydes were generated in the pre-fermented Product 4 during exposure to TSEs, or the above long-term storage episodes. These results confirmed the enhanced peroxidative resistivity of a fermented, antioxidant-fortified natural CLO product over those of non-fermented unrefined products. Product 4: Green Pasture Blue Ice™ Fermented Cod Liver Oil.
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Affiliation(s)
- Benita C. Percival
- Leicester School of Pharmacy, De Montfort University, The Gateway, Leicester LE1 9BH, UK; (B.C.P.); (A.W.); (P.W.)
| | - Angela Wann
- Leicester School of Pharmacy, De Montfort University, The Gateway, Leicester LE1 9BH, UK; (B.C.P.); (A.W.); (P.W.)
- Department of Applied and Human Sciences, Kingston University London, Penrhyn Road, Kingston-upon-Thames KT1 2EE, UK; (G.A.); (A.L.G.); (D.N.)
| | - Richard Zbasnik
- Natural Product Analysis Laboratory, Department of Food Science and Technology, University of Nebraska-Lincoln, 1901 N 21st Street, Lincoln, NE 68588-6205, USA; (R.Z.); (V.S.)
| | - Vicki Schlegel
- Natural Product Analysis Laboratory, Department of Food Science and Technology, University of Nebraska-Lincoln, 1901 N 21st Street, Lincoln, NE 68588-6205, USA; (R.Z.); (V.S.)
| | - Mark Edgar
- Department of Chemistry, University of Loughborough, Epinal Way, Loughborough, LE11 3TU, UK;
| | - Jie Zhang
- Green Pasture Products, 416 E. Fremont Street, O’Neill, NE 68763, USA;
| | - Gilbert Ampem
- Department of Applied and Human Sciences, Kingston University London, Penrhyn Road, Kingston-upon-Thames KT1 2EE, UK; (G.A.); (A.L.G.); (D.N.)
| | - Philippe Wilson
- Leicester School of Pharmacy, De Montfort University, The Gateway, Leicester LE1 9BH, UK; (B.C.P.); (A.W.); (P.W.)
| | - Adam Le Gresley
- Department of Applied and Human Sciences, Kingston University London, Penrhyn Road, Kingston-upon-Thames KT1 2EE, UK; (G.A.); (A.L.G.); (D.N.)
| | - Declan Naughton
- Department of Applied and Human Sciences, Kingston University London, Penrhyn Road, Kingston-upon-Thames KT1 2EE, UK; (G.A.); (A.L.G.); (D.N.)
| | - Martin Grootveld
- Leicester School of Pharmacy, De Montfort University, The Gateway, Leicester LE1 9BH, UK; (B.C.P.); (A.W.); (P.W.)
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Robertson C, Lucas RA, Le Gresley A. Scope and limitations of nuclear magnetic resonance techniques for characterisation and quantitation of vitamin D in complex mixtures. Skin Res Technol 2019; 26:112-120. [PMID: 31549460 DOI: 10.1111/srt.12773] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2019] [Revised: 06/29/2019] [Accepted: 08/22/2019] [Indexed: 11/30/2022]
Abstract
BACKGROUND The accurate determination of vitamin D in skin is of considerable importance in evaluating penetration of skin health products through the different layers of the skin. OBJECTIVE We report on the characterisation and quantitation of vitamin D in an idealised sample and in complex mixtures which mimic that of a typical skin cream, using qNMR, 2D NMR and DOSY techniques. METHODS The characterisation and quantitation conditions were acquired over several heterogeneous samples, allowing for analysis of how the dynamic range and complexity of the different sample mixtures affect the limits of detection (LOD) and limits of quantitation (LOQ) of vitamin D. NMR is of particular value to this task as it is non-destructive, uses a primary ratio method for quantification, and tolerates a wide variety of hydrophilic and hydrophobic components within a given matrix. RESULTS In this investigation, we have attained a trueness level <10%, repeatability values of <1% and brought the limit of quantitation down to 100 nmol/L (≈limit of baseline range of vitamin D2 and D3 per litre seen in vivo), commenting on the limitations observed, such as peak overlap and sensitivity limits. CONCLUSIONS Pure shift optimised sequences allow us to reduce peak overlapping, allowing further characterisation of individual compounds and the separation of complex mixtures using NMR.
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Le Gresley A, Peron JMR. A semi-automatic approach to the characterisation of dark chocolate by Nuclear Magnetic Resonance and multivariate analysis. Food Chem 2019; 275:385-389. [DOI: 10.1016/j.foodchem.2018.09.089] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2018] [Revised: 09/06/2018] [Accepted: 09/14/2018] [Indexed: 01/30/2023]
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Le Gresley A, Ampem G, Grootveld M, Percival BC, Naughton DP. Characterisation of peroxidation products arising from culinary oils exposed to continuous and discontinuous thermal degradation processes. Food Funct 2019; 10:7952-7966. [DOI: 10.1039/c9fo02065a] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
High-resolution NMR analysis has been used, for the first time, to identify, putatively, two new secondary aldehydic lipid oxidation products in culinary oils.
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Affiliation(s)
- Adam Le Gresley
- Department of Chemistry and Pharmaceutical Sciences
- SEC Faculty
- Kingston University
- Kingston-upon-Thames
- UK
| | - Gilbert Ampem
- Department of Chemistry and Pharmaceutical Sciences
- SEC Faculty
- Kingston University
- Kingston-upon-Thames
- UK
| | | | | | - Declan P. Naughton
- Department of Chemistry and Pharmaceutical Sciences
- SEC Faculty
- Kingston University
- Kingston-upon-Thames
- UK
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Butt U, ElShaer A, Snyder LAS, Al-Kinani AA, Le Gresley A, Alany RG. Fatty Acid Based Microemulsions to Combat Ophthalmia Neonatorum Caused by Neisseria gonorrhoeae and Staphylococcus aureus. Nanomaterials (Basel) 2018; 8:nano8010051. [PMID: 29351260 PMCID: PMC5791138 DOI: 10.3390/nano8010051] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/29/2017] [Revised: 01/05/2018] [Accepted: 01/08/2018] [Indexed: 11/16/2022]
Abstract
The bacterial species Neisseria gonorrhoeae (N. gonorrhoeae) and Staphylococcus aureus (S. aureus) are amongst the main microorganisms that cause ophthalmia neonatorum. The current treatment involves the use of various antibiotics such as ciprofloxacin, cephalosporin, ceftriaxone and cefotaxime. However, this treatment strategy is becoming more ineffective due to the antibiotic resistance in N. gonorrhoeae. The current study explores the potential use of fatty acid based microemulsions (ME) to prevent N. gonorrhoeae and S. aureus infections in new-borns' eyes without harmful side effects such as corneal or conjunctiva irritation. Pseudo-ternary phase diagrams were constructed to evaluate microemulsion regions and six different α-linolenic acid based microemulsions were prepared. The prepared formulations were characterized for α-linolenic acid content, size, transparency, zeta potential, Polarized light Microscopy, antimicrobial activity and ex vivo ocular toxicity. The mean droplet size of the ME formulations was in the range of 190.4 to 350.5 nm and polydispersity index (PDI) values were in the range of 0.102 to 0.561. All formulations were found stable upon storage for at least 8 weeks. In addition, self-diffusion coefficients determined by nuclear magnetic resonance (NMR) reflected that the diffusability of water increased at higher than 30% w/w water, while that of fatty acids and surfactants was in reverse. The antimicrobial efficacy of microemulsions was determined against N. gonorrhoeae and S. aureus. It was concluded that all microemulsions have strong antimicrobial effects against N. gonorrhoeae and S. aureus. Finally, bovine corneal opacity permeability (BCOP) and hen's egg chorioallantoic (HET-CAM) tests results showed that all microemulsion formulations were not strong ocular irritants.
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Affiliation(s)
- Ummara Butt
- Drug Discovery, Delivery and Patient Care (DDDPC), School of Life Sciences, Pharmacy and Chemistry, Kingston University, Penrhyn Road, Kingston upon Thames, Surrey KT1 2EE, UK.
| | - Amr ElShaer
- Drug Discovery, Delivery and Patient Care (DDDPC), School of Life Sciences, Pharmacy and Chemistry, Kingston University, Penrhyn Road, Kingston upon Thames, Surrey KT1 2EE, UK.
| | - Lori A S Snyder
- School of Life Sciences, Pharmacy and Chemistry, Kingston University, Kingston upon Thames KT1 2EE, UK.
| | - Ali A Al-Kinani
- Drug Discovery, Delivery and Patient Care (DDDPC), School of Life Sciences, Pharmacy and Chemistry, Kingston University, Penrhyn Road, Kingston upon Thames, Surrey KT1 2EE, UK.
| | - Adam Le Gresley
- Drug Discovery, Delivery and Patient Care (DDDPC), School of Life Sciences, Pharmacy and Chemistry, Kingston University, Penrhyn Road, Kingston upon Thames, Surrey KT1 2EE, UK.
| | - Raid G Alany
- Drug Discovery, Delivery and Patient Care (DDDPC), School of Life Sciences, Pharmacy and Chemistry, Kingston University, Penrhyn Road, Kingston upon Thames, Surrey KT1 2EE, UK.
- School of Pharmacy, University of Auckland, Auckland 1142, New Zealand.
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Bywaters L, Mulcahy-Ryan L, Fielder M, Sinclair A, Le Gresley A. Synthetic scale-up of a novel fluorescent probe and its biological evaluation for surface detection of Staphylococcus aureus. Mol Cell Probes 2017; 36:1-9. [PMID: 28668278 DOI: 10.1016/j.mcp.2017.06.006] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2017] [Revised: 06/01/2017] [Accepted: 06/25/2017] [Indexed: 11/29/2022]
Abstract
This paper reports on the LGX fluorometric test for enzymatic MRSA/MSSA detection. It highlights the reasons rhodamines have been overlooked and also strategies to improve the synthesis of rhodamine-peptide conjugates. Evaluation of the LGX test for detection of MRSA/MSSA on surfaces is undertaken in the presence of potentially confounding E. coli and S. epidermidis for the first time.
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Affiliation(s)
- Luke Bywaters
- Chemistry and Pharmaceutical Sciences, SEC Faculty, Kingston University, Kingston-upon-Thames KT1 2EE, United Kingdom
| | - Lauren Mulcahy-Ryan
- Applied and Human Sciences, SEC Faculty, Kingston University, Kingston-upon-Thames KT1 2EE, United Kingdom
| | - Mark Fielder
- Applied and Human Sciences, SEC Faculty, Kingston University, Kingston-upon-Thames KT1 2EE, United Kingdom
| | - Alex Sinclair
- Chemistry and Pharmaceutical Sciences, SEC Faculty, Kingston University, Kingston-upon-Thames KT1 2EE, United Kingdom
| | - Adam Le Gresley
- Chemistry and Pharmaceutical Sciences, SEC Faculty, Kingston University, Kingston-upon-Thames KT1 2EE, United Kingdom.
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Sinclair A, Mulcahy LE, Geldeard L, Malik S, Fielder MD, Le Gresley A. Development of an in situ culture-free screening test for the rapid detection of Staphylococcus aureus within healthcare environments. Org Biomol Chem 2013; 11:3307-13. [DOI: 10.1039/c3ob40150b] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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Gresley AL, Kenny J, Cassar C, Kelly A, Sinclair A, Fielder MD. The application of high resolution diffusion NMR to the analysis of manuka honey. Food Chem 2012; 135:2879-86. [PMID: 22980885 DOI: 10.1016/j.foodchem.2012.07.072] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2012] [Revised: 07/05/2012] [Accepted: 07/12/2012] [Indexed: 01/15/2023]
Abstract
The application of DOSY (Diffusion Ordered SpectroscopY) NMR as a technique for the virtual separation of key components of manuka honey and the implications for future discriminatory analysis of honey types is reported for the first time. The scope and the limitations of DOSY NMR are considered using the recently conceived DOSY Tool Box processing software and preliminary anti-bacterial data for the different honey types is reported.
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Affiliation(s)
- Adam Le Gresley
- SEC Faculty, Kingston University, Kingston upon Thames KT1 2EE, UK.
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Le Gresley A, Abdullah A, Desai P, Ghosh U, Gollapalli U, Kiran M, Lafon S. Scope of the Heck Reaction in the Synthesis of a New Family of Anthracene Diacrylamide G-Quadruplex Ligands. SYNTHETIC COMMUN 2011. [DOI: 10.1080/00397911.2010.505703] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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Le Gresley A, Abdullah A, Chawla D, Desai P, Ghosh U, Gollapalli U, Kiran M, Lafon S, Sinclair A. Diacrylamides as selective G-quadruplex ligands in in vitro and in vivo assays. Med Chem Commun 2011. [DOI: 10.1039/c1md00020a] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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