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Dobrota CT, Florea AD, Racz CP, Tomoaia G, Soritau O, Avram A, Benea HRC, Rosoiu CL, Mocanu A, Riga S, Kun AZ, Tomoaia-Cotisel M. Dynamics of Dental Enamel Surface Remineralization under the Action of Toothpastes with Substituted Hydroxyapatite and Birch Extract. MATERIALS (BASEL, SWITZERLAND) 2024; 17:2038. [PMID: 38730845 PMCID: PMC11084803 DOI: 10.3390/ma17092038] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/14/2024] [Revised: 04/18/2024] [Accepted: 04/24/2024] [Indexed: 05/13/2024]
Abstract
To address tooth enamel demineralization resulting from factors such as acid erosion, abrasion, and chronic illness treatments, it is important to develop effective daily dental care products promoting enamel preservation and surface remineralization. This study focused on formulating four toothpastes, each containing calcined synthetic hydroxyapatite (HAP) in distinct compositions, each at 4%, along with 1.3% birch extract. Substitution elements were introduced within the HAP structure to enhance enamel remineralization. The efficacy of each toothpaste formulation was evaluated for repairing enamel and for establishing the dynamic of the remineralization. This was performed by using an in vitro assessment of artificially demineralized enamel slices. The structural HAP features explored by XRD and enamel surface quality by AFM revealed notable restorative properties of these toothpastes. Topographic images and the self-assembly of HAP nanoparticles into thin films on enamel surfaces showcased the formulations' effectiveness. Surface roughness was evaluated through statistical analysis using one-way ANOVA followed by post-test Bonferroni's multiple comparison test with a p value < 0.05 significance setting. Remarkably, enamel nanostructure normalization was observed within a short 10-day period of toothpaste treatment. Optimal remineralization for all toothpastes was reached after about 30 days of treatment. These toothpastes containing birch extract also have a dual function of mineralizing enamel while simultaneously promoting enamel health and restoration.
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Affiliation(s)
- Cristina Teodora Dobrota
- Research Center of Excellence in Physical Chemistry, Faculty of Chemistry and Chemical Engineering, Babeş-Bolyai University, 11 Arany Janos St., 400028 Cluj-Napoca, Romania; (C.T.D.); (A.-D.F.); (C.-P.R.); (A.A.); (A.M.); (S.R.); (A.-Z.K.)
- Department of Molecular Biology and Biotechnology, Faculty of Biology and Geology, Babeş-Bolyai University, 44 Republicii St., 400015 Cluj-Napoca, Romania;
| | - Alexandra-Diana Florea
- Research Center of Excellence in Physical Chemistry, Faculty of Chemistry and Chemical Engineering, Babeş-Bolyai University, 11 Arany Janos St., 400028 Cluj-Napoca, Romania; (C.T.D.); (A.-D.F.); (C.-P.R.); (A.A.); (A.M.); (S.R.); (A.-Z.K.)
| | - Csaba-Pal Racz
- Research Center of Excellence in Physical Chemistry, Faculty of Chemistry and Chemical Engineering, Babeş-Bolyai University, 11 Arany Janos St., 400028 Cluj-Napoca, Romania; (C.T.D.); (A.-D.F.); (C.-P.R.); (A.A.); (A.M.); (S.R.); (A.-Z.K.)
| | - Gheorghe Tomoaia
- Department of Orthopedics and Traumatology, Iuliu Hatieganu University of Medicine and Pharmacy, 47 General Traian Mosoiu St., 400132 Cluj-Napoca, Romania; (G.T.)
- Academy of Romanian Scientists, 3 Ilfov St., 050044 Bucharest, Romania
| | - Olga Soritau
- Oncology Institute of Cluj-Napoca, 34-36 Republicii St., 400015 Cluj-Napoca, Romania;
| | - Alexandra Avram
- Research Center of Excellence in Physical Chemistry, Faculty of Chemistry and Chemical Engineering, Babeş-Bolyai University, 11 Arany Janos St., 400028 Cluj-Napoca, Romania; (C.T.D.); (A.-D.F.); (C.-P.R.); (A.A.); (A.M.); (S.R.); (A.-Z.K.)
| | - Horea-Rares-Ciprian Benea
- Department of Orthopedics and Traumatology, Iuliu Hatieganu University of Medicine and Pharmacy, 47 General Traian Mosoiu St., 400132 Cluj-Napoca, Romania; (G.T.)
| | - Cristina Lavinia Rosoiu
- Department of Molecular Biology and Biotechnology, Faculty of Biology and Geology, Babeş-Bolyai University, 44 Republicii St., 400015 Cluj-Napoca, Romania;
| | - Aurora Mocanu
- Research Center of Excellence in Physical Chemistry, Faculty of Chemistry and Chemical Engineering, Babeş-Bolyai University, 11 Arany Janos St., 400028 Cluj-Napoca, Romania; (C.T.D.); (A.-D.F.); (C.-P.R.); (A.A.); (A.M.); (S.R.); (A.-Z.K.)
| | - Sorin Riga
- Research Center of Excellence in Physical Chemistry, Faculty of Chemistry and Chemical Engineering, Babeş-Bolyai University, 11 Arany Janos St., 400028 Cluj-Napoca, Romania; (C.T.D.); (A.-D.F.); (C.-P.R.); (A.A.); (A.M.); (S.R.); (A.-Z.K.)
- Academy of Romanian Scientists, 3 Ilfov St., 050044 Bucharest, Romania
| | - Attila-Zsolt Kun
- Research Center of Excellence in Physical Chemistry, Faculty of Chemistry and Chemical Engineering, Babeş-Bolyai University, 11 Arany Janos St., 400028 Cluj-Napoca, Romania; (C.T.D.); (A.-D.F.); (C.-P.R.); (A.A.); (A.M.); (S.R.); (A.-Z.K.)
| | - Maria Tomoaia-Cotisel
- Research Center of Excellence in Physical Chemistry, Faculty of Chemistry and Chemical Engineering, Babeş-Bolyai University, 11 Arany Janos St., 400028 Cluj-Napoca, Romania; (C.T.D.); (A.-D.F.); (C.-P.R.); (A.A.); (A.M.); (S.R.); (A.-Z.K.)
- Academy of Romanian Scientists, 3 Ilfov St., 050044 Bucharest, Romania
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Racz CP, Racz LZ, Floare CG, Tomoaia G, Horovitz O, Riga S, Kacso I, Borodi G, Sarkozi M, Mocanu A, Roman C, Tomoaia-Cotisel M. Curcumin and whey protein concentrate binding: Thermodynamic and structural approach. Food Hydrocoll 2023. [DOI: 10.1016/j.foodhyd.2023.108547] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/10/2023]
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Chakraborty S, Karmakar A, Mandal S, Goswami T, Ghosh P, Mandal A. Thermoresponsive Reversible Host-Guest Supramolecular Nanotubular Self-Assembly of Octyl-2-acetoxybenzoate@β-CD. J Mol Liq 2022. [DOI: 10.1016/j.molliq.2022.120947] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
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Racz LZ, Racz CP, Pop LC, Tomoaia G, Mocanu A, Barbu I, Sárközi M, Roman I, Avram A, Tomoaia-Cotisel M, Toma VA. Strategies for Improving Bioavailability, Bioactivity, and Physical-Chemical Behavior of Curcumin. Molecules 2022; 27:molecules27206854. [PMID: 36296447 PMCID: PMC9608994 DOI: 10.3390/molecules27206854] [Citation(s) in RCA: 23] [Impact Index Per Article: 11.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2022] [Revised: 10/04/2022] [Accepted: 10/08/2022] [Indexed: 11/23/2022] Open
Abstract
Curcumin (CCM) is one of the most frequently explored plant compounds with various biological actions such as antibacterial, antiviral, antifungal, antineoplastic, and antioxidant/anti-inflammatory properties. The laboratory data and clinical trials have demonstrated that the bioavailability and bioactivity of curcumin are influenced by the feature of the curcumin molecular complex types. Curcumin has a high capacity to form molecular complexes with proteins (such as whey proteins, bovine serum albumin, β-lactoglobulin), carbohydrates, lipids, and natural compounds (e.g., resveratrol, piperine, quercetin). These complexes increase the bioactivity and bioavailability of curcumin. The current review provides these derivatization strategies for curcumin in terms of biological and physico-chemical aspects with a strong focus on different type of proteins, characterization methods, and thermodynamic features of protein–curcumin complexes, and with the aim of evaluating the best performances. The current literature review offers, taking into consideration various biological effects of the CCM, a whole approach for CCM-biomolecules interactions such as CCM-proteins, CCM-nanomaterials, and CCM-natural compounds regarding molecular strategies to improve the bioactivity as well as the bioavailability of curcumin in biological systems.
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Affiliation(s)
- Levente Zsolt Racz
- Research Center in Physical Chemistry, Faculty of Chemistry and Chemical Engineering, Babes-Bolyai University of Cluj-Napoca, 11 Arany Janos Str., RO-400028 Cluj-Napoca, Romania
| | - Csaba Pal Racz
- Research Center in Physical Chemistry, Faculty of Chemistry and Chemical Engineering, Babes-Bolyai University of Cluj-Napoca, 11 Arany Janos Str., RO-400028 Cluj-Napoca, Romania
| | - Lucian-Cristian Pop
- Research Center in Physical Chemistry, Faculty of Chemistry and Chemical Engineering, Babes-Bolyai University of Cluj-Napoca, 11 Arany Janos Str., RO-400028 Cluj-Napoca, Romania
| | - Gheorghe Tomoaia
- Department of Orthopedics and Traumatology, Iuliu Hatieganu University of Medicine and Pharmacy, 47 Gen. Traian Mosoiu Str., RO-400132 Cluj-Napoca, Romania
- Academy of Romanian Scientists, 3 Ilfov Str., RO-050044 Bucharest, Romania
| | - Aurora Mocanu
- Research Center in Physical Chemistry, Faculty of Chemistry and Chemical Engineering, Babes-Bolyai University of Cluj-Napoca, 11 Arany Janos Str., RO-400028 Cluj-Napoca, Romania
| | - Ioana Barbu
- Faculty of Biology and Geology, Babes-Bolyai University, 4-6 Clinicilor Str., RO-400006 Cluj-Napoca, Romania
| | | | - Ioana Roman
- Institute of Biological Research, Branch of NIRDBS Bucharest, 48 Republicii Str., RO-400015 Cluj-Napoca, Romania
| | - Alexandra Avram
- Research Center in Physical Chemistry, Faculty of Chemistry and Chemical Engineering, Babes-Bolyai University of Cluj-Napoca, 11 Arany Janos Str., RO-400028 Cluj-Napoca, Romania
| | - Maria Tomoaia-Cotisel
- Research Center in Physical Chemistry, Faculty of Chemistry and Chemical Engineering, Babes-Bolyai University of Cluj-Napoca, 11 Arany Janos Str., RO-400028 Cluj-Napoca, Romania
- Academy of Romanian Scientists, 3 Ilfov Str., RO-050044 Bucharest, Romania
| | - Vlad-Alexandru Toma
- Faculty of Biology and Geology, Babes-Bolyai University, 4-6 Clinicilor Str., RO-400006 Cluj-Napoca, Romania
- Institute of Biological Research, Branch of NIRDBS Bucharest, 48 Republicii Str., RO-400015 Cluj-Napoca, Romania
- Correspondence:
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Abstract
Due to their unique structural, physical and chemical properties, cyclodextrins and their derivatives have been of great interest to scientists and researchers in both academia and industry for over a century. Many of the industrial applications of cyclodextrins have arisen from their ability to encapsulate, either partially or fully, other molecules, especially organic compounds. Cyclodextrins are non-toxic oligopolymers of glucose that help to increase the solubility of organic compounds with poor aqueous solubility, can mask odors from foul-smelling compounds, and have been widely studied in the area of drug delivery. In this review, we explore the structural and chemical properties of cyclodextrins that give rise to this encapsulation (i.e., the formation of inclusion complexes) ability. This review is unique from others written on this subject because it provides powerful insights into factors that affect cyclodextrin encapsulation. It also examines these insights in great detail. Later, we provide an overview of some industrial applications of cyclodextrins, while emphasizing the role of encapsulation in these applications. We strongly believe that cyclodextrins will continue to garner interest from scientists for many years to come, and that novel applications of cyclodextrins have yet to be discovered.
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Caira MR, Bourne SA, Mzondo B. Encapsulation of the Antioxidant R-(+)-α-Lipoic Acid in Permethylated α- and β-Cyclodextrins: Thermal and X-ray Structural Characterization of the 1:1 Inclusion Complexes. Molecules 2017; 22:E866. [PMID: 28545253 PMCID: PMC6152681 DOI: 10.3390/molecules22060866] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2017] [Revised: 05/16/2017] [Accepted: 05/16/2017] [Indexed: 11/16/2022] Open
Abstract
The naturally occurring compound α-lipoic acid (ALA) is implicated in manifold critical biological roles and its potent antioxidant properties and potential for treatment of various diseases have led to its widespread use as a dietary supplement. However, shortcomings of poor aqueous solubility and low thermal stability have hampered its development as a medicinal agent, prompting the use of cyclodextrins (CDs) to address these problems. The paucity of published structural data on the nature of the interactions between ALA and CDs motivated the present study, which describes the synthesis and X-ray structural elucidation of crystalline inclusion complexes between the biologically relevant R-(+)-α-lipoic acid (RALA) and the host molecules permethylated α-CD (TMA) and permethylated β-CD (TMB). Single crystal X-ray diffraction of TMA·RALA·6H₂O and TMB·RALA revealed significantly different orientations of the RALA molecule within the TMA and TMB cavities, but in both cases the guest molecule is fully encapsulated by the respective parent host molecules and residues of CD molecules of neighboring complex units. While pure RALA melted at 46-48 °C, combined thermal analysis techniques indicated that on heating the respective complexes, the release of RALA occurred at significantly higher onset temperatures, in the range 150-170 °C.
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Affiliation(s)
- Mino R Caira
- Centre for Supramolecular Chemistry Research, Department of Chemistry, University of Cape Town, Rondebosch 7701, South Africa.
| | - Susan A Bourne
- Centre for Supramolecular Chemistry Research, Department of Chemistry, University of Cape Town, Rondebosch 7701, South Africa.
| | - Buntubonke Mzondo
- Centre for Supramolecular Chemistry Research, Department of Chemistry, University of Cape Town, Rondebosch 7701, South Africa.
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Venanzi M, Gatto E, Formaggio F, Toniolo C. The importance of being Aib. Aggregation and self-assembly studies on conformationally constrained oligopeptides. J Pept Sci 2017; 23:104-116. [DOI: 10.1002/psc.2956] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2016] [Revised: 11/30/2016] [Accepted: 12/01/2016] [Indexed: 12/23/2022]
Affiliation(s)
- Mariano Venanzi
- Department of Chemical Sciences and Technologies and Centre for Nanoscience, Nanotechnology and Advanced Instrumentation; University of Rome ‘Tor Vergata’; 00133 Rome Italy
| | - Emanuela Gatto
- Department of Chemical Sciences and Technologies and Centre for Nanoscience, Nanotechnology and Advanced Instrumentation; University of Rome ‘Tor Vergata’; 00133 Rome Italy
| | - Fernando Formaggio
- ICB, Padova Unit, CNR, Department of Chemistry; University of Padova; 35131 Padova Italy
| | - Claudio Toniolo
- ICB, Padova Unit, CNR, Department of Chemistry; University of Padova; 35131 Padova Italy
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8
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Tang P, Wang L, Ma X, Xu K, Xiong X, Liao X, Li H. Characterization and In Vitro Evaluation of the Complexes of Posaconazole with β- and 2,6-di-O-methyl-β-cyclodextrin. AAPS PharmSciTech 2017; 18:104-114. [PMID: 26883260 DOI: 10.1208/s12249-016-0497-z] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2015] [Accepted: 02/01/2016] [Indexed: 11/30/2022] Open
Abstract
Posaconazole is a triazole antifungal drug that with extremely poor aqueous solubility. Up to now, this drug can be administered via intravenous injection and oral suspension. However, its oral bioavailability is greatly limited by the dissolution rate of the drug. This study aimed to improve water solubility and dissolution of posaconazole through characterizing the inclusion complexes of posaconazole with β-cyclodextrin (β-CD) and 2,6-di-O-methyl-β-cyclodextrin (DM-β-CD). Phase solubility studies were performed to calculate the stability constants in solution. The results of FT-IR, PXRD, 1H and ROESY 2D NMR, and DSC all verified the formation of the complexes in solid state. The complexes showed remarkably improved water solubility and dissolution rate than pure posaconazole. Especially, the aqueous solubility of the DM-β-CD complex is nine times higher than that of the β-CD complex. Preliminary in vitro antifungal susceptibility tests showed that the two inclusion complexes maintained high antifungal activities. These results indicated that the DM-β-CD complexes have great potential for application in the delivery of poorly water-soluble antifungal agents, such as posaconazole.
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Tang P, Tang B, Wang Q, Xu K, Xiong X, Li H. Effect of hydroxypropyl-β-cyclodextrin on the bounding of salazosulfapyridine to human serum albumin. Int J Biol Macromol 2016; 92:105-115. [DOI: 10.1016/j.ijbiomac.2016.07.033] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2016] [Revised: 07/08/2016] [Accepted: 07/10/2016] [Indexed: 10/21/2022]
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Messina GML, De Zotti M, Lettieri R, Gatto E, Venanzi M, Formaggio F, Toniolo C, Marletta G. Design of lipidic platforms anchored within nanometric cavities by peptide hooks. RSC Adv 2016. [DOI: 10.1039/c6ra06054d] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023] Open
Abstract
A stable confinement of liposomes within arrays of hybrid polymer/Au nanocavities was achieved using peptide hooks covalently linked to the Au floor.
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Affiliation(s)
- G. M. L. Messina
- Laboratory for Molecular Surfaces and Nanotechnologies (LAMSUN)
- Department of Chemical Sciences
- University of Catania
- Center for Colloids and Surface Science (CSGI)
- 95129 Catania
| | - M. De Zotti
- ICB Padova Unit
- CNR
- Department of Chemistry
- University of Padova
- 35131 Padova
| | - R. Lettieri
- Department of Chemical Sciences and Technologies
- University of Rome “Tor Vergata”
- CSGI
- 00133 Rome
- Italy
| | - E. Gatto
- Department of Chemical Sciences and Technologies
- University of Rome “Tor Vergata”
- CSGI
- 00133 Rome
- Italy
| | - M. Venanzi
- Department of Chemical Sciences and Technologies
- University of Rome “Tor Vergata”
- CSGI
- 00133 Rome
- Italy
| | - F. Formaggio
- ICB Padova Unit
- CNR
- Department of Chemistry
- University of Padova
- 35131 Padova
| | - C. Toniolo
- ICB Padova Unit
- CNR
- Department of Chemistry
- University of Padova
- 35131 Padova
| | - G. Marletta
- Laboratory for Molecular Surfaces and Nanotechnologies (LAMSUN)
- Department of Chemical Sciences
- University of Catania
- Center for Colloids and Surface Science (CSGI)
- 95129 Catania
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van de Streek J, Neumann MA. Validation of molecular crystal structures from powder diffraction data with dispersion-corrected density functional theory (DFT-D). ACTA CRYSTALLOGRAPHICA SECTION B, STRUCTURAL SCIENCE, CRYSTAL ENGINEERING AND MATERIALS 2014; 70:1020-32. [PMID: 25449625 PMCID: PMC4468513 DOI: 10.1107/s2052520614022902] [Citation(s) in RCA: 94] [Impact Index Per Article: 9.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/19/2014] [Accepted: 10/18/2014] [Indexed: 05/14/2023]
Abstract
In 2010 we energy-minimized 225 high-quality single-crystal (SX) structures with dispersion-corrected density functional theory (DFT-D) to establish a quantitative benchmark. For the current paper, 215 organic crystal structures determined from X-ray powder diffraction (XRPD) data and published in an IUCr journal were energy-minimized with DFT-D and compared to the SX benchmark. The on average slightly less accurate atomic coordinates of XRPD structures do lead to systematically higher root mean square Cartesian displacement (RMSCD) values upon energy minimization than for SX structures, but the RMSCD value is still a good indicator for the detection of structures that deserve a closer look. The upper RMSCD limit for a correct structure must be increased from 0.25 Å for SX structures to 0.35 Å for XRPD structures; the grey area must be extended from 0.30 to 0.40 Å. Based on the energy minimizations, three structures are re-refined to give more precise atomic coordinates. For six structures our calculations provide the missing positions for the H atoms, for five structures they provide corrected positions for some H atoms. Seven crystal structures showed a minor error for a non-H atom. For five structures the energy minimizations suggest a higher space-group symmetry. For the 225 SX structures, the only deviations observed upon energy minimization were three minor H-atom related issues. Preferred orientation is the most important cause of problems. A preferred-orientation correction is the only correction where the experimental data are modified to fit the model. We conclude that molecular crystal structures determined from powder diffraction data that are published in IUCr journals are of high quality, with less than 4% containing an error in a non-H atom.
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Affiliation(s)
- Jacco van de Streek
- Department of Pharmacy, University of Copenhagen, Universitetsparken 2, 2100 Copenhagen, Denmark
| | - Marcus A. Neumann
- Avant-garde Materials Simulation Deutschland GmbH, Merzhauser Strasse 177, D-79100 Freiburg, Germany
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Spectroscopic studies of R(+)-α-lipoic acid--cyclodextrin complexes. Int J Mol Sci 2014; 15:20469-85. [PMID: 25387076 PMCID: PMC4264178 DOI: 10.3390/ijms151120469] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2014] [Revised: 10/24/2014] [Accepted: 10/29/2014] [Indexed: 11/29/2022] Open
Abstract
α-Lipoic acid (ALA) has a chiral center at the C6 position, and exists as two enantiomers, R(+)-ALA (RALA) and S(−)-ALA (SALA). RALA is naturally occurring, and is a cofactor for mitochondrial enzymes, therefore playing a major role in energy metabolism. However, RALA cannot be used for pharmaceuticals or nutraceuticals because it readily polymerizes via a 1,2-dithiolane ring-opening when exposed to light or heat. So, it is highly desired to find out the method to stabilize RALA. The purpose of this study is to provide the spectroscopic information of stabilized RALA and SALA through complexation with cyclodextrins (CDs), α-CD, β-CD and γ-CD and to examine the physical characteristics of the resultant complexes in the solid state. The RALA-CD structures were elucidated based on the micro fourier transform infrared (FT-IR) and Raman analyses. The FT-IR results showed that the C=O stretching vibration of RALA appeared at 1717 cm−1 and then shifted on formation of the RALA-CD complexes. The Raman spectra showed that the S–S and C–S stretching vibrations for RALA at 511 cm−1 (S–S), 631 cm−1 (C–S) and 675 cm−1 (C–S) drastically weakened and almost disappeared upon complexation with CDs. Several peaks indicative of O–H vibrations also shifted or changed in intensity. These results indicate that RALA and CDs form host-guest complexes by interacting with one another.
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13
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Crystal structure determination of three polycyclic compounds and comparative Rietveld refinement between MS and GSAS programs. ACTA ACUST UNITED AC 2013. [DOI: 10.1007/s11434-013-5837-8] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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