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Akbari M, Morad R, Maaza M. Effect of silver nanoparticle size on interaction with artemisinin: First principle study. RESULTS IN SURFACES AND INTERFACES 2023. [DOI: 10.1016/j.rsurfi.2023.100104] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 03/06/2023]
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2
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Xie W, Cao B, Zhu H, Raza A, Juckel N, Xie J, Jiang R, Vince R, Lee MK, More SS. Orally Bioavailable Prodrugs of ψ-GSH: A Potential Treatment for Alzheimer's Disease. J Med Chem 2022; 65:14441-14455. [PMID: 36353871 PMCID: PMC9662183 DOI: 10.1021/acs.jmedchem.2c00779] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2022] [Indexed: 11/30/2022]
Abstract
Addressing glycation-induced oxidative stress in Alzheimer's disease (AD) is an emerging pharmacotherapeutic strategy. Restoration of the brain glyoxalase enzyme system that neutralizes reactive dicarbonyls is one such approach. Toward this end, we designed, synthesized, and evaluated a γ-glutamyl transpeptidase-resistant glyoxalase substrate, ψ-GSH. Although mechanistically successful, the oral efficacy of ψ-GSH appeared as an area in need of improvement. Herein, we describe our rationale for the creation of prodrugs that mask the labile sulfhydryl group. In vitro and in vivo stability studies identified promising prodrugs that could deliver pharmacologically relevant brain levels of ψ-GSH. When administered orally to a mouse model generated by the intracerebroventricular injection of Aβ1-42, the compounds conferred cognitive benefits. Biochemical and histological examination confirmed their effects on neuroinflammation and oxidative stress. Collectively, we have identified orally efficacious prodrugs of ψ-GSH that are able to restore brain glyoxalase activity and mitigate inflammatory and oxidative pathology associated with AD.
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Affiliation(s)
- Wei Xie
- Center
for Drug Design, College of Pharmacy, University
of Minnesota, Minneapolis, Minnesota 55455, United States
| | - Bin Cao
- Center
for Drug Design, College of Pharmacy, University
of Minnesota, Minneapolis, Minnesota 55455, United States
| | - Haizhou Zhu
- Center
for Drug Design, College of Pharmacy, University
of Minnesota, Minneapolis, Minnesota 55455, United States
| | - Abbas Raza
- Center
for Drug Design, College of Pharmacy, University
of Minnesota, Minneapolis, Minnesota 55455, United States
| | - Nicholas Juckel
- Department
of Neuroscience, University of Minnesota, Minneapolis, Minnesota 55455, United States
| | - Jiashu Xie
- Center
for Drug Design, College of Pharmacy, University
of Minnesota, Minneapolis, Minnesota 55455, United States
| | - Rongrong Jiang
- Center
for Drug Design, College of Pharmacy, University
of Minnesota, Minneapolis, Minnesota 55455, United States
| | - Robert Vince
- Center
for Drug Design, College of Pharmacy, University
of Minnesota, Minneapolis, Minnesota 55455, United States
| | - Michael K. Lee
- Department
of Neuroscience, University of Minnesota, Minneapolis, Minnesota 55455, United States
- Institute
for Translational Neuroscience, University
of Minnesota, Minneapolis, Minnesota 55455, United States
| | - Swati S. More
- Center
for Drug Design, College of Pharmacy, University
of Minnesota, Minneapolis, Minnesota 55455, United States
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3
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Thammajinno S, Buranachai C, Kanatharana P, Thavarungkul P, Thammakhet-Buranachai C. A copper nanoclusters probe for dual detection of microalbumin and creatinine. SPECTROCHIMICA ACTA. PART A, MOLECULAR AND BIOMOLECULAR SPECTROSCOPY 2022; 270:120816. [PMID: 34995852 DOI: 10.1016/j.saa.2021.120816] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/20/2021] [Revised: 12/21/2021] [Accepted: 12/23/2021] [Indexed: 06/14/2023]
Abstract
A fluorescent probe based on glutathione-capped copper nanoclusters (GSH-CuNCs) was developed for the detection of dual targets, human serum albumin (HSA) and creatinine, in human urine. The GSH-CuNCs were synthesized by a one-pot green method using ascorbic acid as a reducing agent. The detection of HSA was in a turn-on mode via electrostatic interaction in a basic condition while the detection of creatinine was in a turn-off mode via non-covalent bonding in an acidic condition. Under optimal conditions, the linear range and detection limit of HSA were 5.0 nM to 150 nM and 1.510 ± 0.041 nM, while those of creatinine were 30 μM to 1000 μM and 13.0 ± 1.0 μM. This easily fabricated nanocluster probe provided a fast response with high sensitivity, and good selectivity. Recoveries from urine samples were in the range of 81.44 ± 0.25 to 109.22 ± 0.57% for HSA and 80.57 ± 0.16 to 109.0 ± 0.10% for creatinine. The urinary analytical results from the fluorescent probe were in good agreement (P > 0.05) to those obtained from immunoturbidimetric and enzymatic methods, signifying the excellent performance of this sensing system.
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Affiliation(s)
- Supitcha Thammajinno
- Division of Physical Science, Faculty of Science, Prince of Songkla University, Hat Yai, Songkhla 90110, Thailand; Center of Excellence for Trace Analysis and Biosensor, Prince of Songkla University, Hat Yai, Songkhla 90110, Thailand; Center of Excellence for Innovation in Chemistry, Faculty of Science, Prince of Songkla University, Hat Yai, Songkhla 90110, Thailand
| | - Chittanon Buranachai
- Division of Physical Science, Faculty of Science, Prince of Songkla University, Hat Yai, Songkhla 90110, Thailand; Center of Excellence for Trace Analysis and Biosensor, Prince of Songkla University, Hat Yai, Songkhla 90110, Thailand; Thailand Center of Excellence in Physics, Commission on Higher Education, 328 Si Ayutthaya Road, Bangkok 10400, Thailand
| | - Proespichaya Kanatharana
- Division of Physical Science, Faculty of Science, Prince of Songkla University, Hat Yai, Songkhla 90110, Thailand; Center of Excellence for Trace Analysis and Biosensor, Prince of Songkla University, Hat Yai, Songkhla 90110, Thailand; Center of Excellence for Innovation in Chemistry, Faculty of Science, Prince of Songkla University, Hat Yai, Songkhla 90110, Thailand
| | - Panote Thavarungkul
- Division of Physical Science, Faculty of Science, Prince of Songkla University, Hat Yai, Songkhla 90110, Thailand; Center of Excellence for Trace Analysis and Biosensor, Prince of Songkla University, Hat Yai, Songkhla 90110, Thailand; Center of Excellence for Innovation in Chemistry, Faculty of Science, Prince of Songkla University, Hat Yai, Songkhla 90110, Thailand; Thailand Center of Excellence in Physics, Commission on Higher Education, 328 Si Ayutthaya Road, Bangkok 10400, Thailand
| | - Chongdee Thammakhet-Buranachai
- Division of Physical Science, Faculty of Science, Prince of Songkla University, Hat Yai, Songkhla 90110, Thailand; Center of Excellence for Trace Analysis and Biosensor, Prince of Songkla University, Hat Yai, Songkhla 90110, Thailand; Center of Excellence for Innovation in Chemistry, Faculty of Science, Prince of Songkla University, Hat Yai, Songkhla 90110, Thailand.
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Pattnaik S, Chaudhury B, Mohapatra M. Exploration of Inorganic Materials with Antiviral Properties. MATERIALS HORIZONS: FROM NATURE TO NANOMATERIALS 2022:53-74. [DOI: 10.1007/978-981-16-4372-9_4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 07/19/2023]
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5
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Characterization of Biological Material Adsorption to the Surface of Nanoparticles without a Prior Separation Step: a Case Study of Glioblastoma-Targeting Peptide and Lipid Nanocapsules. Pharm Res 2021; 38:681-691. [PMID: 33829340 PMCID: PMC8026175 DOI: 10.1007/s11095-021-03034-8] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2021] [Accepted: 03/23/2021] [Indexed: 11/04/2022]
Abstract
Purpose Current preclinical therapeutic strategies involving nanomedicine require increasingly sophisticated nanosystems and the characterization of the complexity of such nanoassemblies is becoming a major issue. Accurate characterization is often the factor that can accelerate the translational approaches of nanomedicines and their pharmaceutical development to reach the clinic faster. We conducted a case study involving the adsorption of the NFL-TBS.40–63 (NFL) peptide (derived from neurofilaments) to the surface of lipid nanocapsules (LNCs) (a combined nanosystem used to target glioblastoma cells) to develop an analytical approach combining the separation and the quantification in a single step, leading to the characterization of the proportion of free peptide and thus the proportion of peptide adsorbed to the lipid nanocapsule surface. Methods LNC suspensions, NFL peptide solution and LNC/NFL peptide mixtures were characterized using a Size-Exclusion Chromatography method (with a chromatographic apparatus). In addition, this method was compared to centrifugal-filtration devices, currently used in literature for this case study. Results Combining the steps for separation and characterization in one single sequence improved the accuracy and robustness of the data and led to reproducible results. Moreover the data deviation observed for the centrifugal-filtration devices demonstrated the limits for this increasingly used characterization approach, explained by the poor separation quality and highlighting the importance for the method optimization. The high potential of the technique was shown, proving that H-bond and/or electrostatic interactions mediate adsorption of the NFL peptide to the surface of LNCs. Conclusions Used only as a characterization tool, the process using chromatographic apparatus is less time and solvent consuming than classical Size-Exclusion Chromatography columns only used for separation. It could be a promising tool for the scientific community for characterizing the interactions of other combinations of nanosystems and active biological agents. Graphical abstract ![]()
Supplementary Information The online version contains supplementary material available at 10.1007/s11095-021-03034-8.
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Morad R, Akbari M, Rezaee P, Koochaki A, Maaza M, Jamshidi Z. First principle simulation of coated hydroxychloroquine on Ag, Au and Pt nanoparticles. Sci Rep 2021; 11:2131. [PMID: 33483539 PMCID: PMC7822900 DOI: 10.1038/s41598-021-81617-6] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2020] [Accepted: 01/06/2021] [Indexed: 12/27/2022] Open
Abstract
From the first month of the COVID-19 pandemic, the potential antiviral properties of hydroxychloroquine (HCQ) and chloroquine (CQ) against SARS-CoV-2 suggested that these drugs could be the appropriate therapeutic candidates. However, their side effects directed clinical tests towards optimizing safe utilization strategies. The noble metal nanoparticles (NP) are promising materials with antiviral and antibacterial properties that can deliver the drug to the target agent, thereby reducing the side effects. In this work, we applied both the quantum mechanical and classical atomistic molecular dynamics approaches to demonstrate the adsorption properties of HCQ/CQ on Ag, Au, AgAu, and Pt nanoparticles. We found the adsorption energies of HCQ/CQ towards nanoparticles have the following trend: PtNP > AuNP > AuAgNP > AgNP. This shows that PtNP has the highest affinity in comparison to the other types of nanoparticles. The (non)perturbative effects of this drug on the plasmonic absorption spectra of AgNP and AuNP with the time-dependent density functional theory. The effect of size and composition of NPs on the coating with HCQ and CQ were obtained to propose the appropriate candidate for drug delivery. This kind of modeling could help experimental groups to find efficient and safe therapies.
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Affiliation(s)
- Razieh Morad
- UNESCO-UNISA Africa Chair in Nanoscience and Nanotechnology (U2ACN2), College of Graduate Studies, University of South Africa (UNISA), Pretoria, South Africa.,Material Research Division, Nanoscience African Network (NANOAFNET), iThemba LABS-National Research Foundation, Somerset West, 7129, South Africa
| | - Mahmood Akbari
- UNESCO-UNISA Africa Chair in Nanoscience and Nanotechnology (U2ACN2), College of Graduate Studies, University of South Africa (UNISA), Pretoria, South Africa.,Material Research Division, Nanoscience African Network (NANOAFNET), iThemba LABS-National Research Foundation, Somerset West, 7129, South Africa
| | - Parham Rezaee
- Chemistry Department, Sharif University of Technology, 11155-9516, Tehran, Iran
| | - Amin Koochaki
- Chemistry Department, Sharif University of Technology, 11155-9516, Tehran, Iran
| | - Malik Maaza
- UNESCO-UNISA Africa Chair in Nanoscience and Nanotechnology (U2ACN2), College of Graduate Studies, University of South Africa (UNISA), Pretoria, South Africa. .,Material Research Division, Nanoscience African Network (NANOAFNET), iThemba LABS-National Research Foundation, Somerset West, 7129, South Africa.
| | - Zahra Jamshidi
- Chemistry Department, Sharif University of Technology, 11155-9516, Tehran, Iran.
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7
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DFT study of cyclic glycine-alanine dipeptide binding to gold nanoclusters. J Mol Graph Model 2020; 103:107823. [PMID: 33373854 DOI: 10.1016/j.jmgm.2020.107823] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2020] [Revised: 11/10/2020] [Accepted: 12/05/2020] [Indexed: 12/21/2022]
Abstract
In this work, we studied the interactions between cyclic glycine-alanine dipeptide c(GA) and gold nanoclusters (AunNCs, where n = 2-10) using density functional theory (DFT), atoms-in-molecules theory (AIM), and natural bond orbital analysis (NBO). This dipeptide (DP) consists of two amino acid residues (glycine and alanine); thus, the preference of both residues for binding to gold atoms was examined. The preference of alanine residue to the studied AunNCs was found to be greater than that of glycine residue. Two types of interactions were exhibited between the AunNCs and c(GA), the partially-covalent partially-electrostatic type and electrostatic interaction. Performance of two DFT functionals and different basis sets is assessed. The results benchmark the importance of the DFT functional with dispersion and long-range corrections, as well as the polarization functions in the basis sets for the gold lusters-peptide binding. The binding energy (ΔEbind) values of the c(GA)-AunNCs complexes in gas and water implicit solvent were compared with those previously published for cyclic glycine-glycine DP-AunNCs complexes. It was found that the ΔEbind values of the former complexes are greater than those of latter ones in water solvent.
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Lee JJY, Leong WK. Towards understanding the mode of action of the cytotoxic triosmium carbonyl cluster Os3(CO)10(NCCH3)2: Its reactivity with amino acids and oligopeptides. J Organomet Chem 2020. [DOI: 10.1016/j.jorganchem.2020.121459] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
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9
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Edwards EH, Fertig AA, McClelland KP, Meidenbauer MT, Chakraborty S, Krauss TD, Bren KL, Matson EM. Enhancing the activity of photocatalytic hydrogen evolution from CdSe quantum dots with a polyoxovanadate cluster. Chem Commun (Camb) 2020; 56:8762-8765. [PMID: 32628236 DOI: 10.1039/d0cc03163a] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
We report the improvement of photocatalytic proton reduction using molecular polyoxovanadate-alkoxide clusters as hole scavengers for CdSe quantum dots. The increased hydrogen production is explained by favorable charge interactions between reduced forms of the cluster and the charge on the quantum dots arising from the capping ligands.
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Affiliation(s)
- Emily H Edwards
- Department of Chemistry, University of Rochester, Rochester, New York 14627, USA.
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10
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Requejo KI, Liopo AV, Zubarev ER. Gold Nanorod Synthesis with Small Thiolated Molecules. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2020; 36:3758-3769. [PMID: 32216357 DOI: 10.1021/acs.langmuir.0c00302] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
Size and shape tunability have been widely demonstrated for gold nanorods (AuNRs), but reproducible and reliable protocols for the synthesis of small nanocrystals with high yield are still needed for potential biomedical applications. Here, we present novel seed-mediated and seedless protocols for gold nanorods by incorporating bioadditives or small thiolated molecules during the growth stage. The bioadditives glutathione (GSH), oxidized glutathione (GSSG), l-cysteine (l-cys), and l-methionine (l-met) are utilized in nanomolar and micromolar concentrations to modify the aspect ratio of AuNRs in a reproducible form. Overall, smaller aspect ratios are achieved for both synthetic approaches due to reduction in length or increment in length and width depending on the method, type of bioadditive and the strength of its interaction with the nanorod surface. For the seeded synthesis, only GSSG produces large nanorods in high yield, whereas for the seedless method GSH and GSSG form small nanorods with higher quality when compared to controls.
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Affiliation(s)
- Katherinne I Requejo
- Department of Chemistry, Rice University, 6100 S Main Street, Houston, Texas 77005, United States
| | - Anton V Liopo
- Department of Chemistry, Rice University, 6100 S Main Street, Houston, Texas 77005, United States
| | - Eugene R Zubarev
- Department of Chemistry, Rice University, 6100 S Main Street, Houston, Texas 77005, United States
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11
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Taha M, Lee MJ. Influence of the alanine side-chain methyl group on the peptide-gold nanoparticles interactions. J Mol Liq 2020. [DOI: 10.1016/j.molliq.2020.112528] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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12
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Akbari M, Morad R, Maaza M. First principle study of silver nanoparticle interactions with antimalarial drugs extracted from Artemisia annua plant. JOURNAL OF NANOPARTICLE RESEARCH : AN INTERDISCIPLINARY FORUM FOR NANOSCALE SCIENCE AND TECHNOLOGY 2020; 22:331. [PMID: 33132747 PMCID: PMC7588957 DOI: 10.1007/s11051-020-05058-4] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/04/2020] [Accepted: 10/19/2020] [Indexed: 05/21/2023]
Abstract
Silver nanoparticles have a great potential in a broad range of applications such as drug-delivery carriers because of their antiviral and antibacterial properties. In this study, the coating properties of silver nanoparticle (size range of 1.6 nm) with three common anti-malarial drugs, Artemisinin, Artemether, and Artesunate have been studied by using the quantum mechanical and classical atomistic molecular dynamics simulation in order to use as the drug delivery to treat malaria and COVID-19 diseases. The optimized structure, frequencies, charge distribution, and the electrostatic potential maps of the three drug molecules were simulated by using the density functional theory (DFT) at the B3LYP/6-311++g(d,p) level of theory. Then, molecular dynamics simulation was used to study the coating of AgNP with each of these drugs. The affinity of interaction was obtained as Artesunate > Artemether > Artemisinin which is in agreement with the DFT results on the adsorption of drugs on the Ag(111) slab.
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Affiliation(s)
- Mahmood Akbari
- UNESCO-UNISA Africa Chair in Nanoscience & Nanotechnology (U2ACN2), College of Graduate Studies, University of South Africa (UNISA), Pretoria, South Africa
- Nanoscience African Network (NANOAFNET), Material Research Division, iThemba LABS-National Research Foundation, Somerset West, 7129 South Africa
| | - Razieh Morad
- UNESCO-UNISA Africa Chair in Nanoscience & Nanotechnology (U2ACN2), College of Graduate Studies, University of South Africa (UNISA), Pretoria, South Africa
- Nanoscience African Network (NANOAFNET), Material Research Division, iThemba LABS-National Research Foundation, Somerset West, 7129 South Africa
| | - Malik Maaza
- UNESCO-UNISA Africa Chair in Nanoscience & Nanotechnology (U2ACN2), College of Graduate Studies, University of South Africa (UNISA), Pretoria, South Africa
- Nanoscience African Network (NANOAFNET), Material Research Division, iThemba LABS-National Research Foundation, Somerset West, 7129 South Africa
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13
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Exploring the intermolecular interaction of serine and threonine dipeptides with gold nanoclusters and nanoparticles of different shapes and sizes by quantum mechanics and molecular simulations. J Mol Liq 2019. [DOI: 10.1016/j.molliq.2019.111903] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
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14
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Sharma D, Singh T. A DFT study of polyaniline/ZnO nanocomposite as a photocatalyst for the reduction of methylene blue dye. J Mol Liq 2019. [DOI: 10.1016/j.molliq.2019.111528] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
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15
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Mammino L. Effects of complexation with a metal ion on the intramolecular hydrogen bonds in acylphloroglucinols. Theor Chem Acc 2019. [DOI: 10.1007/s00214-019-2481-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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16
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Elistratova J, Faizullin B, Shamsutdinova N, Gubaidullin A, Strelnik I, Babaev V, Kholin K, Nizameev I, Musina E, Khairullin R, Karasik A, Mustafina A. Synthesis of Au(I) complex-based aqueous colloids for sensing of biothiols. Inorganica Chim Acta 2019. [DOI: 10.1016/j.ica.2018.10.006] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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17
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Taha M, Lee MJ. Does the peptide backbone unit interact with gold nanoclusters? Insights from computational modeling. J Biomol Struct Dyn 2018; 37:4258-4266. [PMID: 30466363 DOI: 10.1080/07391102.2018.1546231] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
Communicated by Ramaswamy H. Sarma.
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Affiliation(s)
- Mohamed Taha
- Materials Science and Nanotechnology Department, Faculty of Postgraduate Studies for Advanced Sciences (PSAS), Beni-Suef University , Beni-Suef , Egypt
| | - Ming-Jer Lee
- Department of Chemical Engineering, National Taiwan University of Science & Technology , Taipei , Taiwan
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18
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Chall S, Mati SS, Das I, Kundu A, De G, Chattopadhyay K. Understanding the Effect of Single Cysteine Mutations on Gold Nanoclusters as Studied by Spectroscopy and Density Functional Theory Modeling. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2017; 33:12120-12129. [PMID: 28985680 DOI: 10.1021/acs.langmuir.7b01789] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
Fluorescent metal nanoclusters have generated considerable excitement in nanobiotechnology, particularly in the applications of biolabeling, targeted delivery, and biological sensing. The present work is an experimental and computational study that aims to understand the effects of protein environment on the synthesis and electronic properties of gold nanoclusters. MPT63, a drug target of Mycobacterium tuberculosis, was used as the template protein to synthesize, for the first time, gold nanoclusters at a low micromolar concentration of the protein. Two single cysteine mutants of MPT63, namely, MPT63Gly20Cys (mutant I) and MPT63Gly40Cys (mutant II) were employed for this study. The experimental results show that cysteine residues positioned in two different regions of the protein induce varying electronic states of the nanoclusters depending on the surrounding amino acids. A mixture of five-atom and eight-atom clusters was generated for each mutant, and the former was found to be predominant in both cases. Computational studies, including density functional theory (DFT), frontier molecular orbital (FMO), and natural bond orbital (NBO) calculations, validated the experimental observations. The as-prepared protein-stabilized nanoclusters were found to have applications in the imaging of live cells.
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Affiliation(s)
- Sayantani Chall
- Structural Biology & Bio-Informatics Division, CSIR-Indian Institute of Chemical Biology , 4, Raja S. C. Mallick Road, Kolkata 700032, India
| | - Soumya Sundar Mati
- Department of Chemistry, Government General Degree College, Keshiary , Paschim Medinipur 721135, India
| | - Indranee Das
- CSIR-Central Glass and Ceramic Research Institute , 196, Raja S. C. Mullick Road, Kolkata 700032, India
| | - Amrita Kundu
- Structural Biology & Bio-Informatics Division, CSIR-Indian Institute of Chemical Biology , 4, Raja S. C. Mallick Road, Kolkata 700032, India
| | - Goutam De
- CSIR-Central Glass and Ceramic Research Institute , 196, Raja S. C. Mullick Road, Kolkata 700032, India
| | - Krishnananda Chattopadhyay
- Structural Biology & Bio-Informatics Division, CSIR-Indian Institute of Chemical Biology , 4, Raja S. C. Mallick Road, Kolkata 700032, India
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Huang HY, Cai KB, Chang LY, Chen PW, Lin TN, Lin CAJ, Shen JL, Talite MJ, Chou WC, Yuan CT. Eco-friendly luminescent solar concentrators with low reabsorption losses and resistance to concentration quenching based on aqueous-solution-processed thiolate-gold nanoclusters. NANOTECHNOLOGY 2017; 28:375702. [PMID: 28682300 DOI: 10.1088/1361-6528/aa7e1f] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
Heavy-metal-containing quantum dots (QDs) with engineered electronic states have been served as luminophores in luminescent solar concentrators (LSCs) with impressive optical efficiency. Unfortunately, those QDs involve toxic elements and need to be synthesized in a hazardous solvent. Recently, biocompatible, eco-friendly gold nanoclusters (AuNCs), which can be directly synthesized in an aqueous solution, have gained much attention for promising applications in 'green photonics'. Here, we explored the solid-state photophysical properties of aqueous-solution-processed, glutathione-stabilized gold nanoclusters (GSH-AuNCs) with a ligand-to-metal charge-transfer (LMCT) state for developing 'green' LSCs. We found that such GSH-AuNCs exhibit a large Stokes shift with almost no spectral overlap between the optical absorption and PL emission due to the LMCT states, thus, suppressing reabsorption losses. Compared with GSH-AuNCs in solution, the photoluminescence quantum yields (PL-QYs) of the LSCs can be enhanced, accompanied with a lengthened PL lifetime owing to the suppression of non-radiative recombination rates. In addition, the LSCs do not suffer from severe concentration-induced PL quenching, which is a common weakness for conventional luminophores. As a result, a common trade-off between light-harvesting efficiency and solid-state PL-QYs can be bypassed due to nearly-zero spectral overlap integral between the optical absorption and PL emission. We expect that GSH-AuNCs hold great promise for serving as luminophores for 'green' LSCs by further enhancing solid-state PL-QYs.
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Affiliation(s)
- H Y Huang
- Department of Physics, Chung Yuan Christian University, Taoyuan, Taiwan
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Khandelwal P, Poddar P. Fluorescent metal quantum clusters: an updated overview of the synthesis, properties, and biological applications. J Mater Chem B 2017; 5:9055-9084. [DOI: 10.1039/c7tb02320k] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
A brief history of metal quantum clusters, their synthesis methods, physical properties, and an updated overview of their applications is provided.
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Affiliation(s)
- Puneet Khandelwal
- Physical & Materials Chemistry Division
- CSIR-National Chemical Laboratory
- Pune – 411008
- India
| | - Pankaj Poddar
- Physical & Materials Chemistry Division
- CSIR-National Chemical Laboratory
- Pune – 411008
- India
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21
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Safwat MA, Soliman GM, Sayed D, Attia MA. Gold nanoparticles enhance 5-fluorouracil anticancer efficacy against colorectal cancer cells. Int J Pharm 2016; 513:648-658. [PMID: 27693737 DOI: 10.1016/j.ijpharm.2016.09.076] [Citation(s) in RCA: 57] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2016] [Revised: 09/23/2016] [Accepted: 09/28/2016] [Indexed: 01/06/2023]
Abstract
5-Fluorouracil (5-FU), an antimetabolite drug, is extensively used in the treatment solid tumors. However, its severe side effects limit its clinical benefits. To enhance 5-FU anticancer efficacy and reduce its side effects it was loaded onto gold nanoparticles (GNPs) using two thiol containing ligands, thioglycolic acid (TGA) and glutathione (GSH). The GNPs were prepared at different 5-FU/ligand molar ratios and evaluated using different techniques. Anticancer efficacy of 5-FU/GSH-GNPs was studied using flow cytometry in cancerous tissue obtained from patients having colorectal cancer. The GNPs were spherical in shape and had a size of ∼9-17nm. Stability of the GNPs and drug release were studied as a function of salt concentration and solution pH. Maximum 5-FU loading was achieved at 5-FU/ligand molar ratio of 1:1 and 2:1 for TGA-GNPs and GSH-GNPs, respectively. GNPs coating with pluronic F127 improved their stability against salinity. 5-FU release from GNPs was slow and pH-dependent. 5-FU/GSH-GNPs induced apoptosis and stopped the cell cycle progression in colorectal cancer cells. They also had a 2-fold higher anticancer effect compared with free 5-FU. These results confirm the potential of GNPs to enhance 5-FU anticancer efficacy.
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Affiliation(s)
- Mohamed A Safwat
- Department of Pharmaceutics, Faculty of Pharmacy, Assiut University, Assiut 71526, Egypt; Department of Pharmaceutics and Industrial Pharmacy, Deraya University, El-Minia, Egypt
| | - Ghareb M Soliman
- Department of Pharmaceutics, Faculty of Pharmacy, Assiut University, Assiut 71526, Egypt.
| | - Douaa Sayed
- Department of Clinical Pathology, South Egypt Cancer Institute, Assiut University, Assiut, Egypt
| | - Mohamed A Attia
- Department of Pharmaceutics, Faculty of Pharmacy, Assiut University, Assiut 71526, Egypt
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22
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Charchar P, Christofferson AJ, Todorova N, Yarovsky I. Understanding and Designing the Gold-Bio Interface: Insights from Simulations. SMALL (WEINHEIM AN DER BERGSTRASSE, GERMANY) 2016; 12:2395-418. [PMID: 27007031 DOI: 10.1002/smll.201503585] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/25/2015] [Revised: 02/01/2016] [Indexed: 05/20/2023]
Abstract
Gold nanoparticles (AuNPs) are an integral part of many exciting and novel biomedical applications, sparking the urgent need for a thorough understanding of the physicochemical interactions occurring between these inorganic materials, their functional layers, and the biological species they interact with. Computational approaches are instrumental in providing the necessary molecular insight into the structural and dynamic behavior of the Au-bio interface with spatial and temporal resolutions not yet achievable in the laboratory, and are able to facilitate a rational approach to AuNP design for specific applications. A perspective of the current successes and challenges associated with the multiscale computational treatment of Au-bio interfacial systems, from electronic structure calculations to force field methods, is provided to illustrate the links between different approaches and their relationship to experiment and applications.
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Affiliation(s)
- Patrick Charchar
- School of Engineering, RMIT University, Melbourne, Victoria, 3001, Australia
| | | | - Nevena Todorova
- School of Engineering, RMIT University, Melbourne, Victoria, 3001, Australia
| | - Irene Yarovsky
- School of Engineering, RMIT University, Melbourne, Victoria, 3001, Australia
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23
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Ganguly M, Jana J, Pal A, Pal T. Synergism of gold and silver invites enhanced fluorescence for practical applications. RSC Adv 2016. [DOI: 10.1039/c5ra26430h] [Citation(s) in RCA: 36] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Synergism of gold and silver improves fluorescence behavior of gold–silver bimetallic clusters with practical applications.
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Affiliation(s)
| | - Jayasmita Jana
- Department of Chemistry
- Indian Institute of Technology
- Kharagpur-721302
- India
| | - Anjali Pal
- Department of Civil Engineering
- Indian Institute of Technology
- Kharagpur-721302
- India
| | - Tarasankar Pal
- Department of Chemistry
- Indian Institute of Technology
- Kharagpur-721302
- India
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24
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Devadoss A, Kuragano A, Terashima C, Sudhagar P, Nakata K, Kondo T, Yuasa M, Fujishima A. Single-step electrospun TiO2–Au hybrid electrodes for high selectivity photoelectrocatalytic glutathione bioanalysis. J Mater Chem B 2016; 4:220-228. [DOI: 10.1039/c5tb01740h] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
One-step electrospun Au nanoparticle decorated TiO2 nanofiber membrane served as effective photoanode for highly selective glutathione analysis with a photoelectrocatalytic oxidation process.
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Affiliation(s)
- Anitha Devadoss
- Photocatalysis International Research Center
- Research Institute for Science & Technology
- Tokyo University of Science
- Noda
- Japan
| | - Asako Kuragano
- Photocatalysis International Research Center
- Research Institute for Science & Technology
- Tokyo University of Science
- Noda
- Japan
| | - Chiaki Terashima
- Photocatalysis International Research Center
- Research Institute for Science & Technology
- Tokyo University of Science
- Noda
- Japan
| | - P. Sudhagar
- Photocatalysis International Research Center
- Research Institute for Science & Technology
- Tokyo University of Science
- Noda
- Japan
| | - Kazuya Nakata
- Photocatalysis International Research Center
- Research Institute for Science & Technology
- Tokyo University of Science
- Noda
- Japan
| | - Takeshi Kondo
- Photocatalysis International Research Center
- Research Institute for Science & Technology
- Tokyo University of Science
- Noda
- Japan
| | - Makoto Yuasa
- Photocatalysis International Research Center
- Research Institute for Science & Technology
- Tokyo University of Science
- Noda
- Japan
| | - Akira Fujishima
- Photocatalysis International Research Center
- Research Institute for Science & Technology
- Tokyo University of Science
- Noda
- Japan
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25
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Mielcarek A, Dołęga A. Weak hydrogen bonding interaction S–H···OC studied by FT-IR spectroscopy and DFT calculations. J Mol Struct 2016. [DOI: 10.1016/j.molstruc.2015.09.032] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
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26
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Calborean A, Martin F, Marconi D, Turcu R, Kacso I, Buimaga-Iarinca L, Graur F, Turcu I. Adsorption mechanisms of l-Glutathione on Au and controlled nano-patterning through Dip Pen Nanolithography. MATERIALS SCIENCE & ENGINEERING. C, MATERIALS FOR BIOLOGICAL APPLICATIONS 2015; 57:171-80. [DOI: 10.1016/j.msec.2015.07.042] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/05/2015] [Revised: 06/29/2015] [Accepted: 07/22/2015] [Indexed: 11/16/2022]
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27
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Kumbhar S, Jana S, Anoop A, Waller MP. Cooperativity in bimetallic glutathione complexes. J Mol Graph Model 2015; 62:1-10. [DOI: 10.1016/j.jmgm.2015.05.003] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2015] [Revised: 04/30/2015] [Accepted: 05/05/2015] [Indexed: 01/03/2023]
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28
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Francos MAE, Badía-Laíño R, Díaz-García ME. Fluorescence sensitization of gold-glutathione nanoclusters by aqueous solutions of sodium and potassium ions. Mikrochim Acta 2015. [DOI: 10.1007/s00604-015-1475-y] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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29
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de Villiers CA, Lapsley MC, Hall EAH. A step towards mobile arsenic measurement for surface waters. Analyst 2015; 140:2644-55. [PMID: 25822044 DOI: 10.1039/c4an02368d] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Surface modified quantum dots (QDs) are studied using a bio-inspired cysteine rich ligand (glutathione, GSH) and their quenching response and selectivity to arsenic examined. As predicted from As(3+) binding with highly crosslinked phytochelatin-(PCn)-like molecules, better arsenic selectivity is obtained for a thicker more 3-dimensional GSH surface layer, with exposed sulfhydryl groups. A detection limit of at least 10 μM can be achieved using CdSe/ZnS core-shell QDs capped with this GSH structure. The system is also demonstrated using a mobile phone camera to record the measurement, producing a detection limit of 5 μM. However, copper remains the main interferent of concern. Water-soluble CdTe QDs show little sensitivity to As(3+) even with a GSH surface, but they remain sensitive to Cu(2+), allowing a copper baseline to be established from the CdTe measurement. Despite anticipating that spectrally non overlapping fluorescence would be required from the two types of QDs to achieve this, a method is demonstrated using RGB channels from a mobile phone and processing the raw data for CdTe QDs, with an emission wavelength of 600 nm, and CdSe/ZnS QDs, with emission maximum of 630 nm. It is shown that As(3+) measurement remains feasible at the WHO guideline value of 10 μg L(-1) up to a copper concentration of around 0.3 μM Cu(2+), which corresponds to the highest recorded level in a selection of large rivers world-wide.
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Affiliation(s)
- C A de Villiers
- Institute of Biotechnology, Department of Chemical Engineering and Biotechnology, University of Cambridge, Tennis Court Road, Cambridge, CB2 1QT, UK.
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30
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Ganguly M, Jana J, Mondal C, Pal A, Pal T. Green synthesis of highly fluorescent Au(i)@Ag2/Ag3-thiolate core–shell particles for selective detection of cysteine and Pb(ii). Phys Chem Chem Phys 2014; 16:18185-97. [DOI: 10.1039/c4cp01782j] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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31
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Zhou G, Chang J, Cui S, Pu H, Wen Z, Chen J. Real-time, selective detection of Pb(2+) in water using a reduced graphene oxide/gold nanoparticle field-effect transistor device. ACS APPLIED MATERIALS & INTERFACES 2014; 6:19235-41. [PMID: 25296985 DOI: 10.1021/am505275a] [Citation(s) in RCA: 45] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/20/2023]
Abstract
A field-effect transistor (FET) device-based sensor is developed to specifically detect Pb(2+) ions in an aqueous environment that is notably toxic. Reduced graphene oxide (rGO), as the semiconducting channel material, was utilized in the FET device through a self-assembly method. An l-glutathione reduced was employed as the capture probe for the label-free detection. By monitoring the electrical characteristics of the FET device, the performance of the sensor was measured and investigated. Compared with conventional detection technologies, this sensor enabled real-time detection with a response time of 1-2 s. A lower detection limit for Pb(2+) ions as low as 10 nM was achieved, which is much lower than the maximum contaminant level for Pb(2+) ions in drinking water recommended by the World Health Organization. Furthermore, the rGO FET sensor was able to distinguish Pb(2+) from other metal ions. Without any sample pretreatment, the platform is user-friendly.
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Affiliation(s)
- Guihua Zhou
- Department of Mechanical Engineering, University of Wisconsin-Milwaukee , 3200 North Cramer Street, Milwaukee, Wisconsin 53211, United States
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32
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Schmidbaur H, Raubenheimer HG, Dobrzańska L. The gold-hydrogen bond, Au-H, and the hydrogen bond to gold, Au∙∙∙H-X. Chem Soc Rev 2013; 43:345-80. [PMID: 23999756 DOI: 10.1039/c3cs60251f] [Citation(s) in RCA: 164] [Impact Index Per Article: 14.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
In the first part of this review, the characteristics of Au-H bonds in gold hydrides are reviewed including the data of recently prepared stable organometallic complexes with gold(I) and gold(III) centers. In the second part, the reports are summarized where authors have tried to provide evidence for hydrogen bonds to gold of the type Au∙∙∙H-X. Such interactions have been proposed for gold atoms in the Au(-I), Au(0), Au(I), and Au(III) oxidation states as hydrogen bonding acceptors and H-X units with X = O, N, C as donors, based on both experimental and quantum chemistry studies. To complement these findings, the literature was screened for examples with similar molecular geometries, for which such bonding has not yet been considered. In the discussion of the results, the recently issued IUPAC definitions of hydrogen bonding and the currently accepted description of agostic interactions have been used as guidelines to rank the Au∙∙∙H-X interactions in this broad range of weak chemical bonding. From the available data it appears that all the intra- and intermolecular Au∙∙∙H-X contacts are associated with very low binding energies and non-specific directionality. To date, the energetics have not been estimated, because there are no thermochemical and very limited IR/Raman and temperature-dependent NMR data that can be used as reliable references. Where conspicuous structural or spectroscopic effects have been observed, explanations other than hydrogen bonding Au∙∙∙H-X can also be advanced in most cases. Although numerous examples of short Au∙∙∙H-X contacts exist in the literature, it seems, at this stage, that these probably make only very minor contributions to the energy of a given system and have only a marginal influence on molecular conformations which so far have most often attracted researchers to this topic. Further, more dedicated investigations will be necessary before well founded conclusions can be drawn.
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Affiliation(s)
- Hubert Schmidbaur
- Department Chemie, Technische Universität München, Garching, Germany.
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33
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Ganguly M, Pal J, Das S, Mondal C, Pal A, Negishi Y, Pal T. Green synthesis and reversible dispersion of a giant fluorescent cluster in solid and liquid phase. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2013; 29:10945-10958. [PMID: 23906499 DOI: 10.1021/la402440z] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/02/2023]
Abstract
A water-soluble highly fluorescent silver cluster on Au(I) surface has been synthesized with green chemistry under sunlight. The evolution of the silver cluster is synergistic, demanding gold and glutathione. The fluorescent Au(I)core-Ag(0)shell particles are huge in size and at the same time they are robust. That is why they become a deliverable fluorescing solid upon drying. Again, the giant particles run into common water miscible solvents. As a result, the fluorescence intensity increases to a great extent without any alteration of emission maxima. In this respect, acetone has been found to be the best-suited solvent. To have a universal applicability of the fluorescent clusters, the particles in the water pool of a reverse micelle have been prepared to transfer the particles into different water immiscible solvents. The comparatively lower fluorescence intensity of the particles has been ascribed to a space confinement effect. Finally, giant-cluster-impregnated yellow-orange fluorescent polymer film and fluorescent cotton wool, as well as paper substrate, have been prepared. The antibacterial activity of the fluorescent particle has also been tested involving modified cotton wool and paper substrate for Gram-negative and -positive Escherichia coli and Staphylococcus aureus, respectively.
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Affiliation(s)
- Mainak Ganguly
- Department of Chemistry, Indian Institute of Technology, Kharagpur-721302, India
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34
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Witts RN, Hopson EC, Koballa DE, Van Boening TA, Hopkins NH, Patterson EV, Nagan MC. Backbone-base interactions critical to quantum stabilization of transfer RNA anticodon structure. J Phys Chem B 2013; 117:7489-97. [PMID: 23742318 DOI: 10.1021/jp400084p] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
Transfer RNA (tRNA) anticodons adopt a highly ordered 3'-stack without significant base overlap. Density functional theory at the M06-2X/6-31+G(d,p) level in combination with natural bond orbital analysis was utilized to calculate the intramolecular interactions within the tRNA anticodon that are responsible for stabilizing the stair-stepped conformation. Ten tRNA X-ray crystal structures were obtained from the PDB databank and were trimmed to include only the anticodon bases. Hydrogenic positions were added and optimized for the structures in the stair-stepped conformation. The sugar-phosphate backbone has been retained for these calculations, revealing the role it plays in RNA structural stability. It was found that electrostatic interactions between the sugar-phosphate backbone and the base provide the most stability, rather than the traditionally studied interbase stacking. Base-stacking interactions, though present, were weak and inconsistent. Aqueous solvation was found to have little effect on the intramolecular interactions.
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Affiliation(s)
- Rachel N Witts
- Department of Chemistry, Truman State University, 100 East Normal, Kirksville, Missouri 63501, USA
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35
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Aldeek F, Muhammed MAH, Palui G, Zhan N, Mattoussi H. Growth of highly fluorescent polyethylene glycol- and zwitterion-functionalized gold nanoclusters. ACS NANO 2013; 7:2509-21. [PMID: 23394608 DOI: 10.1021/nn305856t] [Citation(s) in RCA: 137] [Impact Index Per Article: 12.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/05/2023]
Abstract
We have prepared and characterized a new set of highly fluorescent gold nanoclusters (AuNCs) using one-step aqueous reduction of a gold precursor in the presence of bidentate ligands made of lipoic acid anchoring groups, appended with either a poly(ethylene glycol) short chain or a zwitterion group. The AuNCs fluoresce in the red to near-infrared region of the optical spectrum with emission centered at ∼750 nm and a quantum yield of ∼10-14%, and they exhibit long fluorescence lifetimes (up to ∼300 ns). Dispersions of these AuNCs exhibit great long-term colloidal stability, over a wide range of pHs (2-13) and in the presence of high electrolyte concentrations, and a strong resistance to reducing agents such as glutathione. The growth strategy further permitted the controlled, in situ functionalization of the NCs with reactive groups (e.g., carboxylic acid or amine), making these nanoclusters compatible with common and simple-to-implement coupling strategies, such as carbodiimide chemistry. These properties combined make these fluorescent NCs greatly promising for use in various imaging and sensing applications where NIR and long-lived excitations are desired.
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Affiliation(s)
- Fadi Aldeek
- Department of Chemistry and Biochemistry, Florida State University, 95 Chieftan Way, Tallahassee, Florida 32306, United States
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36
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Javan MJ, Jamshidi Z, Tehrani ZA, Fattahi A. Interactions of coinage metal clusters with histidine and their effects on histidine acidity; theoretical investigation. Org Biomol Chem 2012; 10:9373-82. [PMID: 23108513 DOI: 10.1039/c2ob25711d] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Understanding the nature of interaction between metal nanoparticles and biomolecules such as amino acids is important in the development and design of biosensors. In this paper, binding of M(3) clusters (M = Au, Ag and Cu) with neutral and anionic forms of histidine amino acid was studied using density functional theory (DFT-B3LYP). It was found that the interaction of histidine with M(3) clusters is governed by two major bonding factors: (a) the anchoring N-M and O-M bonds and (b) the nonconventional N-H···M and O-H···M hydrogen bonds. The nature of these chemical bonds has been investigated based on quantum theory of atoms in molecules (QTAIM) and natural bond orbital (NBO) analyses. In the next step, the effects of Au, Ag and Cu metal clusters on the gas-phase acidity of weak organic acid (histidine) have been explored. The acidity of isolated histidine was compared with the acidity of its Au(3)-, Ag(3)- and Cu(3)-complexed species. Results indicate that upon complexation with M(3) clusters (at 298 K), the gas-phase acidity (GPA) of histidine varies from 339.5 to 312.3, 315.0, and 313.7 kcal mol(-1) for Au(3)-, Ag(3)- and Cu(3)-His complexes, respectively (i.e., its dissociation becomes much less endothermic). These values indicate that a weak organic acid can be converted to a super acid when it is complexed with metal clusters. Also, in order to investigate the acidity value of the imidazole moiety in histidine, histidine methyl ester (His-OMe) was selected. Similarly, the acidity of this compound was compared with the acidity of their Au(3), Ag(3) and Cu(3)-complexed species. After complexation with M(3) clusters at 298 K, the gas-phase acidity (GPA) of His-OMe varies from 333.0 to 280.0, 304.2 and 291.5 kcal mol(-1), respectively. Moreover, pK(a) values were determined in water for isolated and complexed species of His and His-OMe. The resulting pK(a) values were found to decrease upon complexation with M(3) clusters.
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Affiliation(s)
- Marjan Jebeli Javan
- Department of Chemistry, Sharif University of Technology, P.O. Box: 11365-9516, Tehran, Iran
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