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Bicak B. Structural, spectroscopic, molecular docking, ADME, molecular dynamics studies of Val-Trp dipeptide. J Biomol Struct Dyn 2023; 41:13873-13890. [PMID: 36843537 DOI: 10.1080/07391102.2023.2183041] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2022] [Accepted: 02/14/2023] [Indexed: 02/28/2023]
Abstract
Hypertension is a significant risk factor for various diseases, especially heart, brain, and kidney diseases. It is known that many peptides have the property of lowering blood pressure and determine as ACE inhibitors. The purpose of this study is to obtain information about the molecular structure of Val-Trp (L-valyl-L-tryptophan), which is one of the antihypertensive peptides, by molecular mechanical, quantum mechanical, and spectroscopic methods (FT-IR and Raman). Also, it is aimed to investigate the interactions of Val-Trp dipeptide with receptors related to hypertension and to determine the pharmacokinetic profile due to the potential of the peptide to be a drug candidate. The peptide structure was optimized by DFT/B3LYP/6-311++G(d,p) basis set, then vibrational wavenumbers, molecular electrostatic potential (MEP), HOMO-LUMO (highest occupied molecular orbital- lowest unoccupied molecular orbital), NBO (natural bond orbital) analyzes were performed. The assignment of fundamental theoretical vibration wavenumbers was carried out with potential energy distribution analysis (PED). After the structural analyzes of the peptide were performed, the interactions of the peptide with Angiotensin-converting enzyme (ACE), Angiotensin II Receptor Type 1 (AT1R) and Renin were investigated by molecular docking study. Then, the molecular dynamic (MD) simulation of the peptide-ACE complex with the best binding affinity in the molecular docking studies was carried out for 50 ns. ADME (absorption, distribution, metabolism, and excretion) analysis of Val-Trp dipeptide was performed. In support of the studies carried out, enlightening information about the feasibility of the antihypertensive drug of Val-Trp dipeptide with the help of the ADME profile was presented to the literature.Communicated by Ramaswamy H. Sarma.
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Affiliation(s)
- Bilge Bicak
- Physics Department, Science Faculty, Istanbul University, Istanbul, Turkey
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2
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Investigation on Growth, Growth kinetics and Characterization of L-valine L-valinium perchlorate monohydrate single crystal. J Mol Struct 2022. [DOI: 10.1016/j.molstruc.2022.134408] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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3
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Joice Malini M, Kunjitham R, Sangeetha M, Ramalingam S. Electro-optic property evaluation, vibrational analysis and optical investigation on NLO crystal; Nickel sulfate doped L-Valine crystal using theoretical tools. Chem Phys Lett 2021. [DOI: 10.1016/j.cplett.2020.138268] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
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4
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Król-Górniak A, Pomastowski P, Railean-Plugaru V, Žuvela P, Wong MW, Pauter K, Szultka-Młyńska M, Buszewski B. The study of the molecular mechanism of Lactobacillus paracasei clumping via divalent metal ions by electrophoretic separation. J Chromatogr A 2021; 1652:462127. [PMID: 34214833 DOI: 10.1016/j.chroma.2021.462127] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2020] [Revised: 03/17/2021] [Accepted: 03/26/2021] [Indexed: 11/18/2022]
Abstract
In this work, the molecular mechanism of Lactobacillus paracasei bio-colloid clumping under divalent metal ions treatment such as zinc, copper and magnesium at constant concentrations was studied. The work involved experimental (electrophoretic - capillary electrophoresis in pseudo-isotachophoresis mode, spectroscopic and spectrometric - FT-IR and MALDI-TOF-MS, microscopic - fluorescent microscopy, and flow cytometry) and theoretical (DFT calculations of model complex systems) characterization. Electrophoretic results have pointed out the formation of aggregates under the Zn2+ and Cu2+ modification, whereas the use of the Mg2+ allowed focusing the zone of L. paracasei biocolloid. According to the FT-IR analysis, the major functional groups involved in the aggregation are deprotonated carboxyl and amide groups derived from the bacterial surface structure. Nature of the divalent metal ions was shown to be one of the key factors influencing the bacterial aggregation process. Proteomic analysis showed that surface modification had a considerable impact on bacteria molecular profiles and protein expression, mainly linked to the activation of carbohydrate and nucleotides metabolism as well with the transcription regulation and membrane transport. Density-functional theory (DFT) calculations of modeled Cu2+, Mg2+ and Zn2+ coordination complexes support the interaction between the divalent metal ions and bacterial proteins. Consequently, the possible mechanism of the aggregation phenomenon was proposed. Therefore, this comprehensive study could be further applied in evaluation of biocolloid aggregation under different types of metal ions.
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Affiliation(s)
- Anna Król-Górniak
- Chair of Environmental Chemistry and Bioanalytics, Faculty of Chemistry, Poland; Centre for Modern Interdisciplinary Technologies, Nicolaus Copernicus University, 7 Gagarina Str., 87-100 Torun, Poland
| | - Paweł Pomastowski
- Centre for Modern Interdisciplinary Technologies, Nicolaus Copernicus University, 7 Gagarina Str., 87-100 Torun, Poland
| | - Viorica Railean-Plugaru
- Chair of Environmental Chemistry and Bioanalytics, Faculty of Chemistry, Poland; Centre for Modern Interdisciplinary Technologies, Nicolaus Copernicus University, 7 Gagarina Str., 87-100 Torun, Poland
| | - Petar Žuvela
- Department of Chemistry, National University of Singapore, 3 Science Drive 3, 117543, Singapore
| | - Ming Wah Wong
- Department of Chemistry, National University of Singapore, 3 Science Drive 3, 117543, Singapore
| | - Katarzyna Pauter
- Chair of Environmental Chemistry and Bioanalytics, Faculty of Chemistry, Poland; Centre for Modern Interdisciplinary Technologies, Nicolaus Copernicus University, 7 Gagarina Str., 87-100 Torun, Poland
| | - Małgorzata Szultka-Młyńska
- Chair of Environmental Chemistry and Bioanalytics, Faculty of Chemistry, Poland; Centre for Modern Interdisciplinary Technologies, Nicolaus Copernicus University, 7 Gagarina Str., 87-100 Torun, Poland
| | - Bogusław Buszewski
- Chair of Environmental Chemistry and Bioanalytics, Faculty of Chemistry, Poland; Centre for Modern Interdisciplinary Technologies, Nicolaus Copernicus University, 7 Gagarina Str., 87-100 Torun, Poland.
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Pompei S, Tirillò J, Sarasini F, Santulli C. Development of Thermoplastic Starch (TPS) Including Leather Waste Fragments. Polymers (Basel) 2020; 12:polym12081811. [PMID: 32806698 PMCID: PMC7464409 DOI: 10.3390/polym12081811] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2020] [Revised: 08/07/2020] [Accepted: 08/11/2020] [Indexed: 11/16/2022] Open
Abstract
A thermoplastic starch (TPS) material is developed, based on corn starch plasticized with glycerol and citric acid in a 9:3:1 ratio and further bonded with isinglass and mono- and diglycerides of fatty acids (E471). In TPS, leather fragments, in the amount of 7.5 15 or 22.5 g/100 g of dry matter, were also introduced. The mixture was heated at a maximum temperature of 80 °C, then cast in an open mold to obtain films with thickness in the range 300 ± 50 microns. The leather fragments used were based on collagen obtained from production waste from shoemaking and tanned with tannins obtained from smoketree (Rhus cotinus), therefore free from chromium. Thermogravimetric (TGA) tests suggested that material degradation started at a temperature around 285 °C, revealing that the presence of leather fragments did not influence the occurrence of this process in TPS. Tensile tests indicated an increase in tensile properties (strength and Young's modulus) with increasing leather content, albeit coupled, especially at 22.5 wt%, with a more pronounced brittle behavior. Leather waste provided a sound interface with the bulk of the composite, as observed under scanning electron microscopy. The production process indicated a very limited degradation of the material after exposure to UV radiation for eight days, as demonstrated by the slight attenuation of amide I (collagen) and polysaccharide FTIR peaks. Reheating at 80 °C resulted in a weight loss not exceeding 3%.
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Affiliation(s)
- Silvio Pompei
- School of Architecture and Design, Università di Camerino, viale della Rimembranza, 63100 Ascoli Piceno, Italy;
| | - Jacopo Tirillò
- Department of Chemical Engineering Materials Environment and UdR INSTM, Sapienza Università di Roma, Via Eudossiana 18, 00184 Roma, Italy; (J.T.); (F.S.)
| | - Fabrizio Sarasini
- Department of Chemical Engineering Materials Environment and UdR INSTM, Sapienza Università di Roma, Via Eudossiana 18, 00184 Roma, Italy; (J.T.); (F.S.)
| | - Carlo Santulli
- School of Sciences and Technologies, Università di Camerino, via Gentile III da Varano 7, 62032 Camerino, Italy
- Correspondence: ; Tel.: +39-380-652-2232
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Buszewski B, Rodzik A, Railean-Plugaru V, Sprynskyy M, Pomastowski P. A study of zinc ions immobilization by β-lactoglobulin. Colloids Surf A Physicochem Eng Asp 2020. [DOI: 10.1016/j.colsurfa.2020.124443] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
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Wu HJ, Tanabe K, Nagai H, Sato M. Photo-Induced Super-hydrophilic Thin Films on Quartz Glass by UV Irradiation of Precursor Films Involving a Ti(IV) Complex at Room Temperature. MATERIALS 2019; 12:ma12030348. [PMID: 30678036 PMCID: PMC6384566 DOI: 10.3390/ma12030348] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/21/2018] [Revised: 01/13/2019] [Accepted: 01/17/2019] [Indexed: 01/25/2023]
Abstract
Photo-induced super-hydrophilic thin films were fabricated on a quartz glass substrate by ultraviolet (UV) irradiation of a molecular precursor film at room temperature. A molecular precursor film exhibiting high solubility to both ethanol and water was obtained by spin-coating a solution involving a Ti(IV) complex; this complex was prepared by the reaction of Ti(IV) alkoxide with butylammonium hydrogen oxalate and hydrogen peroxide in ethanol. Transparent and well-adhered amorphous thin films of 160–170 nm thickness were obtained by weak UV irradiation (4 mW·cm−2 at 254 nm) of the precursor films for over 4 h at room temperature. The resultant thin films exhibiting low refractive indices of 1.78–1.79 were mechanically robust and water-insoluble. The chemical components of the thin films were examined by means of Fourier transform-infrared (FT-IR) and X-ray photoelectron spectroscopy (XPS) spectra, focusing on the presence of the original ligands. The super-hydrophilic properties (evaluated based on the water contact angles on the surfaces) of the thin films after being kept in a dark condition overnight emerged when the aforementioned UV-light irradiation was performed for 10 min. It was additionally clarified that the super-hydrophilicity can be photo-induced repeatedly by UV irradiation for 10 min (indicated by a contact angle smaller than 4°) even after the hydrophilic level of the thin films had once been lowered by being in a dark condition for 4 h.
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Affiliation(s)
- Hsiang-Jung Wu
- Applied Chemistry and Chemical Engineering Program, Graduate School, Kogakuin University of Technology and Engineering, 2665-1 Nakano, Hachioji, Tokyo 192-0015, Japan.
| | - Kota Tanabe
- Department of Applied Physics, School of Advanced Engineering, Kogakuin University of Technology and Engineering, 2665-1 Nakano, Hachioji, Tokyo 192-0015, Japan.
| | - Hiroki Nagai
- Department of Applied Physics, School of Advanced Engineering, Kogakuin University of Technology and Engineering, 2665-1 Nakano, Hachioji, Tokyo 192-0015, Japan.
| | - Mitsunobu Sato
- Department of Applied Physics, School of Advanced Engineering, Kogakuin University of Technology and Engineering, 2665-1 Nakano, Hachioji, Tokyo 192-0015, Japan.
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Anand S, Sundararajan RS, Ramachandraraja C, Ramalingam S, Durga R. Molecular vibrational investigation [FT-IR, FT-Raman, UV-Visible and NMR] on Bis(thiourea) Nickel chloride using HF and DFT calculations. SPECTROCHIMICA ACTA. PART A, MOLECULAR AND BIOMOLECULAR SPECTROSCOPY 2015; 138:203-215. [PMID: 25498815 DOI: 10.1016/j.saa.2014.11.032] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/27/2014] [Revised: 10/27/2014] [Accepted: 11/20/2014] [Indexed: 06/04/2023]
Abstract
In the present research work, the FT-IR, FT-Raman spectra of the Bis(thiourea) Nickel chloride (BTNC) were recorded and analyzed. The observed fundamental frequencies in finger print and functional group regions were assigned according to their uniqueness region. The computational calculations were carried out by HF and DFT (B3LYP and B3PW91) methods with 6-31++G(d,p) and 6-311++G(d,p) basis sets and the corresponding results were tabulated. The present organo-metallic compound was made up of covalent and coordination covalent bonds. The modified vibrational pattern of the complex molecule associated with ligand group was analyzed. Furthermore, the (13)C NMR and (1)H NMR spectral data were calculated by using the gauge independent atomic orbital (GIAO) method with B3LYP/6-311++G(d,p) basis set and their spectra were simulated and the chemical shifts linked to TMS were compared. A investigation on the electronic and optical properties; absorption wavelengths, excitation energy, dipole moment and frontier molecular orbital energies were carried out. The kubo gap of the present compound was calculated related to HOMO and LUMO energies which confirm the occurring of charge transformation between the base and ligand. Besides frontier molecular orbitals (FMO), molecular electrostatic potential (MEP) was performed. The NLO properties related to Polarizability and hyperpolarizability based on the finite-field approach were also discussed.
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Affiliation(s)
- S Anand
- Department of Physics, A.V.C. College, Mayiladuthurai, Tamil Nadu, India.
| | - R S Sundararajan
- Department of Physics, Government Arts College, Kumbakonam, Tamil Nadu, India
| | - C Ramachandraraja
- Department of Physics, Government Arts College, Kumbakonam, Tamil Nadu, India
| | - S Ramalingam
- Department of Physics, A.V.C. College, Mayiladuthurai, Tamil Nadu, India
| | - R Durga
- Department of Physics, A.V.C. College, Mayiladuthurai, Tamil Nadu, India
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Lee JW, Hwang CS. White Light Emission from a Colloidal Mixture Containing ZnS Based Nanocrystals: ZnS, ZnS:Cu and ZnS:Mn. B KOREAN CHEM SOC 2014. [DOI: 10.5012/bkcs.2014.35.1.189] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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10
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Kanagathara N, Marchewka MK, Drozd M, Renganathan NG, Gunasekaran S, Anbalagan G. FT-IR, FT-Raman spectra and DFT calculations of melaminium perchlorate monohydrate. SPECTROCHIMICA ACTA. PART A, MOLECULAR AND BIOMOLECULAR SPECTROSCOPY 2013; 112:343-350. [PMID: 23685801 DOI: 10.1016/j.saa.2013.04.001] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/25/2012] [Revised: 03/23/2013] [Accepted: 04/01/2013] [Indexed: 06/02/2023]
Abstract
Melaminium perchlorate monohydrate (MPM), an organic material has been synthesized by slow solvent evaporation method at room temperature. Powder X-ray diffraction analysis confirms that MPM crystal belongs to triclinic system with space group P-1. FTIR and FT Raman spectra are recorded at room temperature. Functional group assignment has been made for the melaminium cations and perchlorate anions. Vibrational spectra have also been discussed on the basis of quantum chemical density functional theory (DFT) calculations using Firefly (PC GAMESS) version 7.1 G. Vibrational frequencies are calculated and scaled values are compared with experimental values. The assignment of the bands has been made on the basis of the calculated PED. The Mulliken charges, HOMO-LUMO orbital energies are analyzed directly from Firefly program log files and graphically illustrated. HOMO-LUMO energy gap and other related molecular properties are also calculated. The theoretically constructed FT-IR and FT-Raman spectra of MPM coincide with the experimental one. The chemical structure of the compound has been established by (1)H and (13)C NMR spectra. No detectable signal was observed during powder test for second harmonic generation.
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Affiliation(s)
- N Kanagathara
- Department of Physics, Vel Tech Multi Tech Dr. Rangarajan Dr. Sakunthala Engg. College, Avadi, Chennai 600 062, India
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Manimaran D, Jesintha John C, Rastogi VK, Hubert Joe I. Growth and vibrational spectral investigation of nonlinear optical crystal L-Argininum Perchlorate-DFT study. SPECTROCHIMICA ACTA. PART A, MOLECULAR AND BIOMOLECULAR SPECTROSCOPY 2013; 109:173-178. [PMID: 23523760 DOI: 10.1016/j.saa.2013.02.024] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/30/2012] [Revised: 02/05/2013] [Accepted: 02/12/2013] [Indexed: 06/02/2023]
Abstract
Nonlinear optical active L-Argininum Perchlorate single crystals are grown by slow evaporation technique. The second-order NLO properties of the molecule are studied by Kurtz-Perry powder technique. FT-IR, FT-Raman spectra have been recorded and analyzed. The equilibrium geometry, vibrational wavenumbers and the first order hyperpolarizability have been calculated with the aid of density functional theoretical method. The NBO analysis explains the intramolecular interactions, electron densities within the molecule. It also confirms the presence of weak intermolecular C-H···O hydrogen bonding in the molecule. The blue-shift in CH stretching wavenumbers is due to the C-H···O hydrogen bonding. The Mulliken population analysis on atomic charges and the HOMO, LUMO energies were also calculated.
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Affiliation(s)
- D Manimaran
- Centre for Molecular and Biophysics Research, Department of Physics, Mar Ivanios College, Thiruvananthapuram 695 015, Kerala, India
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Sajimol AM, Roselin A, Sreevalsa VG, Deepa GD, Bhat Sarita G, Jayalekshmi S. Highly luminescent and biocompatible, L-citrulline-capped ZnS:Mn nanocrystals for rapid screening of metal accumulating Lysinibacillus fusiformis bacteria. LUMINESCENCE 2013; 28:461-7. [PMID: 23494908 DOI: 10.1002/bio.2477] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2012] [Revised: 11/10/2012] [Accepted: 12/01/2012] [Indexed: 11/07/2022]
Abstract
Biocompatible and highly luminescent manganese doped zinc sulfide (ZnS:Mn) nanocrystals of average particle size 10 nm have been synthesized by capping with a novel amino acid ligand, L-citrulline. Though there are many reports on the bioimaging applications of nanostructured semiconductors, the present study focused on the detection of a special type of metal accumulating bacteria, Lysinibacillus fusiformis. This bacterium has significant applications in the disposal of metal components from industrial effluents. In this context, the detection of this bacterium is quite important and the present work demonstrates a novel technique for this bacterial detection. The synthesized nanocrystals were attached to Lysinibacillus fusiformis and characteristics of the bioconjugated system were studied. The blue shift observed in the ultraviolet-visible absorption and photoluminescence spectra of the bioconjugated system, confirms conjugation of the Lysinibacillus fusiformis with L-citrulline-capped ZnS:Mn. When the bioconjugated system (capped ZnS:Mn + bacteria) was observed using a fluorescent microscope under excitation wavelengths 365.4 nm (ultraviolet), 435.8 nm (blue) and 546.1 nm (green), fluorescence emissions were obtained in yellow, green and red regions respectively. The study of relative growth of Lysinibacillus fusiformis in the presence of L-citrulline-capped ZnS:Mn proves biocompatible property of these nanocrystals and their tunable color properties under different excitation wavelengths make them ideal for biolabeling applications.
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Affiliation(s)
- Augustine M Sajimol
- Department of Physics, Cochin University of Science and Technology, Kochi-22, Kerala, India
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Jesintha John C, Xavier TS, Lukose G, Hubert Joe I. Electronic absorption and vibrational spectra and nonlinear optical properties of L-valinium succinate. SPECTROCHIMICA ACTA. PART A, MOLECULAR AND BIOMOLECULAR SPECTROSCOPY 2012; 85:66-73. [PMID: 22020163 DOI: 10.1016/j.saa.2011.09.013] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/21/2011] [Revised: 09/06/2011] [Accepted: 09/07/2011] [Indexed: 05/31/2023]
Abstract
FT-Raman and FTIR techniques have been applied to investigate the potential nonlinear optical material l-valinium succinate. A detailed interpretation of the vibrational spectra was carried out with the aid of potential energy distribution analysis. Density functional theory is applied to explore the nonlinear optical properties of the molecule. Good consistency is found between the calculated results and the experimental data for IR and Raman spectra. The natural bond orbital analysis confirms the occurrence of strong intramolecular N-H⋯O hydrogen bonding.
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Affiliation(s)
- C Jesintha John
- Centre for Molecular and Biophysics Research, Department of Physics, Mar Ivanios College, Thiruvananthapuram 695 015, Kerala, India
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Zhang K, Lam KF, Albela B, Xue T, Khrouz L, Hou QW, Yuan EH, He MY, Bonneviot L. Mononuclear-dinuclear equilibrium of grafted copper complexes confined in the nanochannels of MCM-41 silica. Chemistry 2011; 17:14258-66. [PMID: 22068981 DOI: 10.1002/chem.201102026] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2011] [Indexed: 11/11/2022]
Abstract
Following the structural concept of copper-containing proteins in which dinuclear copper centers are connected by hydroxide bridging ligands, a bidentate copper(II) complex has been incorporated into nano-confined MCM-41 silica by a multistep sequential grafting technique. Characterization by a combination of EPR spectroscopy, X-ray photoelectron spectroscopy (XPS), UV/Vis spectroscopy, IR spectroscopy , and solid-state (13)C and (29)Si cross-polarization magic-angle spinning (CP-MAS) NMR suggests that dinuclear Cu complexes are bridged by hydroxide and other counterions (chloride or perchlorate ions), similar to the situation for EPR-undetectable [Cu(II)···Cu(II)] dimer analogues in biological systems. More importantly, a dynamic mononuclear-dinuclear equilibrium between different coordination modes of copper is observed, which strongly depends on the nature of the counterions (Cl(-) or ClO(4)(-)) in the copper precursor and the pore size of the silica matrix (the so-called confinement effect). A proton-transfer mechanism within the hydrogen-bonding network is suggested to explain the dynamic nature of the dinuclear copper complex supported on the MCM-41 silica.
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Affiliation(s)
- Kun Zhang
- Shanghai Key Laboratory of Green Chemistry and Chemical Processes, Department of Chemistry, East China Normal University, 3663 Zhongshan North Road, 200062, Shanghai, China.
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Thakur P, Joshi SS, Kapoor S, Mukherjee T. Structural phase behavior and vibrational spectroscopic studies of biofunctionalized CdS nanoparticles. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2009; 25:6334-6340. [PMID: 19408904 DOI: 10.1021/la900437x] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
Biomodified CdS nanoparticles were synthesized using l-cysteine as a capping agent in the colloidal state as a function of pH. The role of pH on the size and structure of CdS nanoparticles was investigated in detail. At pH 7.4 and 9.1, X-ray diffraction spectra of as prepared samples showed the presence of a mixture of cubic and hexagonal phases while cubic phase was formed at pH 11.2. A gradual transition to the hexagonal phase was observed for refluxed samples at pH 9.1 and 11.2. Whereas, at pH 7.4, the sample remains in a mixture of cubic and hexagonal phase even after refluxing. The particle size of as prepared samples was about 2 nm, and for refluxed samples the size increased up to 10 nm. The binding of cadmium through thiol group is evidenced by infrared spectra. An intense band due to C-C-N vibration was observed after 24 h of reflux. The formation of a specific molecular cluster determines the growth of a particular phase. Transmission electron microscopy (TEM) studies support the X-ray diffraction (XRD) studies and exhibit well separated spherical particles while refluxed samples show clustering.
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Affiliation(s)
- Priya Thakur
- Department of Chemistry, University of Pune, Pune-411007, India
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Thakur P, Joshi SS, Kapoor S, Mukherjee T. Fluorescence behavior of cysteine-mediated Ag@CdS nanocolloids. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2009; 25:6377-6384. [PMID: 19469470 DOI: 10.1021/la8042507] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
Ag@CdS quantum dots were synthesized by a colloidal method. CdS nanoparticles stabilized by L-cysteine were doped with varying silver concentrations. Ag@CdS nanoparticles were characterized by UV-visible spectroscopy, steady-state and time-resolved fluorescence, X-ray diffraction, Fourier transform infrared resonance (FTIR), and transmission electron microscopy. The effect of dopant concentration and effect of aging of Ag@CdS colloids were studied. At low silver content, emission was found to enhance, while at high silver content, emission quenching was observed after aging. Ag-CdS nanocolloids exhibited multiexponential decay with tau2 being a long-lived component. X-ray diffraction spectra of as prepared samples indicated that silver occupies an interstitial position, while for annealed samples, Ag+ ions get oxidized to Ag2+ and substituted for Cd2+ in the CdS lattice. FTIR studies have shown that cysteine acts as a monodentate ligand for cadmium and silver for as-prepared sample, whereas it acts as a tridentate ligand for annealed samples toward silver. Transmission electron microscopy of as-prepared samples showed spherical-shaped composites with a uniform layer of capping molecules.
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Affiliation(s)
- Priya Thakur
- Department of Chemistry, University of Pune, Pune 411007, India
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Syntheses and Optical Properties of the Water-Dispersible ZnS:Mn Nanocrystals Surface Capped by L-Aminoacid Ligands: Arginine, Cysteine, Histidine, and Methionine. B KOREAN CHEM SOC 2007. [DOI: 10.5012/bkcs.2007.28.7.1091] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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Kalyanaraman S, Krishnakumar V, Ganesan K. Vibrational spectroscopic analysis of cytosine monohydrate and its copper(II) complex. SPECTROCHIMICA ACTA. PART A, MOLECULAR AND BIOMOLECULAR SPECTROSCOPY 2007; 66:1340-6. [PMID: 16920005 DOI: 10.1016/j.saa.2006.04.046] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/09/2006] [Accepted: 04/15/2006] [Indexed: 05/11/2023]
Abstract
Single crystals of cytosine monohydrate and its copper(II) complex were grown by slow evaporation in an aqueous solution at room temperature. The solubility studies were carried out at different temperatures in deionized water. Cytosine monohydrate and the copper(II) complex of cytosine were characterized by recording IR, Raman and UV spectra. The various vibrational modes of the crystals have been classified using factor group and site group analysis. Vibrational assignments were proposed for both the systems based on the spectral investigations.
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Affiliation(s)
- S Kalyanaraman
- Department of Physics, Sri Paramakalyani College, Alwarkurichi, India
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Synthesis of the Water Dispersible L-Valine Capped ZnS:Mn Nanocrystal and the Crystal Structure of the Precursor Complex: [Zn(Val)2(H2O)]. B KOREAN CHEM SOC 2006. [DOI: 10.5012/bkcs.2006.27.11.1809] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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Morsali A, Ranjbar ZR, Amiri MG, Askarinejad A, Xiao HP. Synthesis, structural and spectroscopic characterization of a new cadmium(II) complex containing imidazole (Im) as ligand, [Cd(Im)6](ClO4)2. J COORD CHEM 2006. [DOI: 10.1080/00958970500440462] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
Affiliation(s)
- Ali Morsali
- a Department of Chemistry , School of Sciences , Tarbiat Modarres University , P.O. Box 14155-4838, Tehran, Iran
| | - Zohreh Rashidi Ranjbar
- a Department of Chemistry , School of Sciences , Tarbiat Modarres University , P.O. Box 14155-4838, Tehran, Iran
| | - Maryam Ghoreishi Amiri
- a Department of Chemistry , School of Sciences , Tarbiat Modarres University , P.O. Box 14155-4838, Tehran, Iran
| | - Azadeh Askarinejad
- a Department of Chemistry , School of Sciences , Tarbiat Modarres University , P.O. Box 14155-4838, Tehran, Iran
| | - Hong-Ping Xiao
- b School of Chemistry and Materials Science , Wenzhou Normal College , Wenzhou 325027, People's Republic of China
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