1
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Buglak AA, Nguyen MT. Interactions of coinage metal nanoclusters with low-molecular-weight biocompounds. Biophys Rev 2024; 16:441-477. [PMID: 39309127 PMCID: PMC11415565 DOI: 10.1007/s12551-024-01200-x] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2024] [Accepted: 05/21/2024] [Indexed: 09/25/2024] Open
Abstract
Nowadays, coinage metal nanoclusters (NCs) are largely presented in diagnostics, bioimaging, and biocatalysis due to their high biocompatibility, chemical stability, and sensitivity to surrounding biomolecules. Silver and gold NCs are usually characterized by intense luminescence and photostability, which is in great demand in the detection of organic compounds, ions, pH, temperature, etc. The experimental synthesis of metal NCs often occurs on biopolymer templates, mostly DNA and proteins. However, this review mainly focuses on the interactions with small biomolecules (SBMs) of a molecular weight less than 1000 Da: amino acids, nucleobases, thiolates, oligopeptides, etc. Such molecules can serve as the templates for an eco-friendly facile one-pot synthesis of biocompatible luminescent NCs. The latter aspect makes NCs suitable for diagnostics and intracellular bioimaging. Another important aspect is the interaction of clusters with biomarkers, which is largely exploited by nanosensors: biomarker detection often occurs through either fluorescence emission "turn-on" or "turn-off" mechanisms. Moreover, as theoretical studies show, electronic absorption spectra and Raman spectra of the metal-organic complexes allow efficient detection of various analytes. In this regard, both theoretical and experimental studies of SBM complexes with metal NCs are in great demand. Therefore, this review aims to summarize up-to-date studies on the interaction of small biomolecules with coinage metal NCs from both theoretical and experimental viewpoints.
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Affiliation(s)
- Andrey A. Buglak
- Faculty of Physics, St. Petersburg State University, 199034 Saint-Petersburg, Russia
| | - Minh Tho Nguyen
- Laboratory for Chemical Computation and Modeling, Institute for Computational Science and Artificial Intelligence, Van Lang University, Ho Chi Minh City, 70000 Vietnam
- Faculty of Applied Technology, School of Technology, Van Lang University, Ho Chi Minh City, 70000 Vietnam
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2
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Setzler C, Arrington CA, Lewis D, Petty JT. Breaching the Fortress: Photochemistry of DNA-Caged Ag 106. J Phys Chem B 2023; 127:10851-10860. [PMID: 38054435 PMCID: PMC10749453 DOI: 10.1021/acs.jpcb.3c06358] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2023] [Revised: 11/26/2023] [Accepted: 11/27/2023] [Indexed: 12/07/2023]
Abstract
A DNA strand can encapsulate a silver molecule to create a nanoscale, aqueous stable chromophore. A protected cluster that strongly fluoresces can also be weakly photolabile, and we describe the laser-driven photochemistry of the green fluorophore C4AC4TC3GT4/Ag106+. The embedded cluster is selectively photoexcited at 490 nm and then bleached, and we describe how the efficiency, products, and route of this photochemical reaction are controlled by the DNA cage. With irradiation at 496.5 nm, the cluster absorption progressively drops to give a photodestruction quantum yield of 1.5 (±0.2) × 10-4, ∼103× less efficient than fluorescence. A new λabs = 335 nm chromophore develops because the precursor with 4 Ag0 is converted into a group of clusters with 2 Ag0 - Ag64+, Ag75+, Ag86+, and Ag97+. The 4-7 Ag+ in this series are chemically distinct from the 2 Ag0 because they are selectively etched by iodide. This halide precipitates silver to favor only the smallest Ag64+ cluster, but the larger clusters re-develop when the precipitated Ag+ ions are replenished. DNA-bound Ag106+ decomposes because it is electronically excited and then reacts with oxygen. This two-step process may be state-specific because O2 quenches the red luminescence from Ag106+. However, the rate constant of 2.3 (±0.2) × 106 M-1 s-1 is relatively small, which suggests that the surrounding DNA matrix hinders O2 diffusion. On the basis of analogous photoproducts with methylene blue, we propose that a reactive oxygen species is produced and then oxidizes Ag106+ to leave behind a loose Ag+-DNA skeleton. These findings underscore the ability of DNA scaffolds to not only tune the spectra but also guide the reactions of their molecular silver adducts.
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Affiliation(s)
- Caleb
J. Setzler
- Department
of Chemistry, Furman University, Greenville, South Carolina 29163, United States
| | - Caleb A. Arrington
- Department
of Chemistry, Wofford College, Spartanburg, South Carolina 29303, United States
| | - David Lewis
- Department
of Chemistry, Furman University, Greenville, South Carolina 29163, United States
| | - Jeffrey T. Petty
- Department
of Chemistry, Furman University, Greenville, South Carolina 29163, United States
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3
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Rück V, Mishra NK, Sørensen KK, Liisberg MB, Sloth AB, Cerretani C, Mollerup CB, Kjaer A, Lou C, Jensen KJ, Vosch T. Bioconjugation of a Near-Infrared DNA-Stabilized Silver Nanocluster to Peptides and Human Insulin by Copper-Free Click Chemistry. J Am Chem Soc 2023; 145:16771-16777. [PMID: 37441791 PMCID: PMC10402711 DOI: 10.1021/jacs.3c04768] [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: 05/08/2023] [Indexed: 07/15/2023]
Abstract
DNA-stabilized silver nanoclusters (DNA-AgNCs) are biocompatible emitters with intriguing properties. However, they have not been extensively used for bioimaging applications due to the lack of structural information and hence predictable conjugation strategies. Here, a copper-free click chemistry method for linking a well-characterized DNA-AgNC to molecules of interest is presented. Three different peptides and a small protein, human insulin, were tested as labeling targets. The conjugation to the target compounds was verified by MS, HPLC, and time-resolved anisotropy measurements. Moreover, the spectroscopic properties of DNA-AgNCs were found to be unaffected by the linking reactions. For DNA-AgNC-conjugated human insulin, fluorescence imaging studies were performed on Chinese hamster ovary (CHO) cells overexpressing human insulin receptor B (hIR-B). The specific staining of the CHO cell membranes demonstrates that DNA-AgNCs are great candidates for bioimaging applications, and the proposed linking strategy is easy to implement when the DNA-AgNC structure is known.
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Affiliation(s)
- Vanessa Rück
- Department
of Chemistry, University of Copenhagen, Universitetsparken 5, 2100 Copenhagen, Denmark
| | - Narendra K. Mishra
- Department
of Chemistry, University of Copenhagen, Thorvaldsensvej 40, 1871 Frederiksberg C, Denmark
| | - Kasper K. Sørensen
- Department
of Chemistry, University of Copenhagen, Thorvaldsensvej 40, 1871 Frederiksberg C, Denmark
| | - Mikkel B. Liisberg
- Department
of Chemistry, University of Copenhagen, Universitetsparken 5, 2100 Copenhagen, Denmark
| | - Ane B. Sloth
- Department
of Clinical Physiology and Nuclear Medicine, Copenhagen University Hospital − Rigshospitalet, Blegdamsvej 9, 2100 Copenhagen, Denmark
- Cluster
for Molecular Imaging, Department of Biomedical Sciences, University of Copenhagen, Blegdamsvej 3B, 2200 Copenhagen, Denmark
| | - Cecilia Cerretani
- Department
of Chemistry, University of Copenhagen, Universitetsparken 5, 2100 Copenhagen, Denmark
| | - Christian B. Mollerup
- Department
of Forensic Medicine, University of Copenhagen, Frederik V’s Vej 11, 2100 Copenhagen, Denmark
| | - Andreas Kjaer
- Department
of Clinical Physiology and Nuclear Medicine, Copenhagen University Hospital − Rigshospitalet, Blegdamsvej 9, 2100 Copenhagen, Denmark
- Cluster
for Molecular Imaging, Department of Biomedical Sciences, University of Copenhagen, Blegdamsvej 3B, 2200 Copenhagen, Denmark
| | - Chenguang Lou
- Department
of Physics, Chemistry and Pharmacy, University
of Southern Denmark, Campusvej 55, 5230 Odense M, Denmark
| | - Knud J. Jensen
- Department
of Chemistry, University of Copenhagen, Thorvaldsensvej 40, 1871 Frederiksberg C, Denmark
| | - Tom Vosch
- Department
of Chemistry, University of Copenhagen, Universitetsparken 5, 2100 Copenhagen, Denmark
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4
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Lewis D, Setzler C, Goodwin PM, Thomas K, Branham M, Arrington CA, Petty JT. Interrupted DNA and Slow Silver Cluster Luminescence. THE JOURNAL OF PHYSICAL CHEMISTRY. C, NANOMATERIALS AND INTERFACES 2023; 127:10574-10584. [PMID: 37313118 PMCID: PMC10258842 DOI: 10.1021/acs.jpcc.3c01050] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 02/15/2023] [Revised: 05/16/2023] [Indexed: 06/15/2023]
Abstract
A DNA-silver cluster conjugate is a hierarchical chromophore with a partly reduced silver core embedded within the DNA nucleobases that are covalently linked by the phosphodiester backbone. Specific sites within a polymeric DNA can be targeted to spectrally tune the silver cluster. Here, the repeated (C2A)6 strand is interrupted with a thymine, and the resulting (C2A)2-T-(C2A)4 forms only Ag106+, a chromophore with both prompt (∼1 ns) green and sustained (∼102 μs) red luminescence. Thymine is an inert placeholder that can be removed, and the two fragments (C2A)2 and (C2A)4 also produce the same Ag106+ adduct. In relation to (C2A)2T(C2A)4, the (C2A)2 + (C2A)4 pair is distinguished because the red Ag106+ luminescence is ∼6× lower, relaxes ∼30% faster, and is quenched ∼2× faster with O2. These differences suggest that a specific break in the phosphodiester backbone can regulate how a contiguous vs broken scaffold wraps and better protects its cluster adduct.
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Affiliation(s)
- David Lewis
- Department
of Chemistry, Furman University, Greenville, South Carolina 29163, United States
| | - Caleb Setzler
- Department
of Chemistry, Furman University, Greenville, South Carolina 29163, United States
| | - Peter M. Goodwin
- Center
for Integrated Nanotechnologies, Mail Stop K771, Los Alamos National Laboratory, Los Alamos, New Mexico 87545, United States
| | - Kirsten Thomas
- Department
of Chemistry, Furman University, Greenville, South Carolina 29163, United States
| | - Makayla Branham
- Department
of Chemistry, Furman University, Greenville, South Carolina 29163, United States
| | - Caleb A. Arrington
- Department
of Chemistry, Wofford College, Spartanburg, South Carolina 29303, United States
| | - Jeffrey T. Petty
- Department
of Chemistry, Furman University, Greenville, South Carolina 29163, United States
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5
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David F, Setzler C, Sorescu A, Lieberman RL, Meilleur F, Petty JT. Mapping H + in the Nanoscale (A 2C 4) 2-Ag 8 Fluorophore. J Phys Chem Lett 2022; 13:11317-11322. [PMID: 36453924 DOI: 10.1021/acs.jpclett.2c03161] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/17/2023]
Abstract
When strands of DNA encapsulate silver clusters, supramolecular optical chromophores develop. However, how a particular structure endows a specific spectrum remains poorly understood. Here, we used neutron diffraction to map protonation in (A2C4)2-Ag8, a green-emitting fluorophore with a "Big Dipper" arrangement of silvers. The DNA host has two substructures with distinct protonation patterns. Three cytosines from each strand collectively chelate handle-like array of three silvers, and calorimetry studies suggest Ag+ cross-links. The twisted cytosines are further joined by hydrogen bonds from fully protonated amines. The adenines and their neighboring cytosine from each strand anchor a dipper-like group of five silvers via their deprotonated endo- and exocyclic nitrogens. Typically, exocyclic amines are strongly basic, so their acidification and deprotonation in (A2C4)2-Ag8 suggest that silvers perturb the electron distribution in the aromatic nucleobases. The different protonation states in (A2C4)2-Ag8 suggest that atomic level structures can pinpoint how to control and tune the electronic spectra of these nanoscale chromophores.
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Affiliation(s)
- Fred David
- Department of Chemistry, Furman University, Greenville, South Carolina 29613, United States
| | - Caleb Setzler
- Department of Chemistry, Furman University, Greenville, South Carolina 29613, United States
| | - Alexandra Sorescu
- Department of Chemistry, Furman University, Greenville, South Carolina 29613, United States
| | - Raquel L Lieberman
- School of Chemistry & Biochemistry, Georgia Institute of Technology, Atlanta, Georgia 30332-0400, United States
| | - Flora Meilleur
- Department of Molecular and Structural Biochemistry, North Carolina State University, Campus Box 7622, Raleigh, North Carolina 27695, United States
- Neutron Scattering Division, Oak Ridge National Laboratory, PO Box 2008, Oak Ridge, Tennessee 37831, United States
| | - Jeffrey T Petty
- Department of Chemistry, Furman University, Greenville, South Carolina 29613, United States
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6
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Petty JT, Lewis D, Carnahan S, Kim D, Couch C. Tug-of-War between DNA Chelation and Silver Agglomeration in DNA-Silver Cluster Chromophores. J Phys Chem B 2022; 126:3822-3830. [PMID: 35594191 DOI: 10.1021/acs.jpcb.2c01054] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Supramolecular chromophores form when a DNA traps silvers that then coalesce into clusters with discrete, molecular electronic states. However, DNA strands are polymeric ligands that disperse silvers and thus curb agglomeration. We study this competition using two chromophores that share three common components: a dimeric DNA scaffold, Ag+-nucleobase base pairs, and Ag0 chromophores. The DNA host C4-A2-iC4T mimics structural elements in a DNA-cluster crystal structure using a phosphodiester backbone with combined 5' → 3' and 3' → 5' (indicated by "i") directions. The backbone directions must alternate to form the two silver clusters, and this interdependence supports a silver-linked structure. This template creates two chromophores with distinct sizes, charges, and hence spectra: (C4-A2-iC4T)2/Ag117+ with λabs/λem = 430/520 nm and (C4-A2-iC4T)2/Ag148+ with λabs/λem = 510/630 nm. The Ag+ and Ag0 constituents in these partially oxidized clusters are linked with structural elements in C4-A2-iC4T. Ag+ alone binds sparsely but strongly to form C4-A2-iC4T/3-4 Ag+ and (C4-A2-iC4T)2/7-8 Ag+ complexes, and these stoichiometries suggest that Ag+ cross-links pairs of cytosines to form a hairpin with a metallo-C4/iC4 duplex and an adenine loop. The Ag0 are chemically orthogonal because they can be oxidatively etched without disrupting the underlying Ag+-DNA matrix, and their reactivity is attributed to their valence electrons and weaker chelation by the adenines. These studies suggest that Ag+ disperses with the cytosines to create an adenine binding pocket for the Ag0 cluster chromophores.
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Affiliation(s)
- Jeffrey T Petty
- Department of Chemistry, Furman University, Greenville, South Carolina 29613, United States
| | - David Lewis
- Department of Chemistry, Furman University, Greenville, South Carolina 29613, United States
| | - Savannah Carnahan
- Department of Chemistry, Furman University, Greenville, South Carolina 29613, United States
| | - Dahye Kim
- Department of Chemistry, Furman University, Greenville, South Carolina 29613, United States
| | - Caroline Couch
- Department of Chemistry, Furman University, Greenville, South Carolina 29613, United States
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7
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Li T, Hu Z, Yu S, Liu Z, Zhou X, Liu R, Liu S, Deng Y, Li S, Chen H, Chen Z. DNA Templated Silver Nanoclusters for Bioanalytical Applications: A Review. J Biomed Nanotechnol 2022. [DOI: 10.1166/jbn.2022.3344] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
Due to their unique programmability, biocompatibility, photostability and high fluorescent quantum yield, DNA templated silver nanoclusters (DNA Ag NCs) have attracted increasing attention for bioanalytical application. This review summarizes the recent developments in fluorescence
properties of DNA templated Ag NCs, as well as their applications in bioanalysis. Finally, we herein discuss some current challenges in bioanalytical applications, to promote developments of DNA Ag NCs in biochemical analysis.
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Affiliation(s)
- Taotao Li
- Hunan Provincial Key Lab of Dark Tea and Jin-Hua, School of Materials and Chemical Engineering, Hunan City University, Yiyang 413000, China
| | - Zhiyuan Hu
- Hunan Provincial Key Lab of Dark Tea and Jin-Hua, School of Materials and Chemical Engineering, Hunan City University, Yiyang 413000, China
| | - Songlin Yu
- Hunan Provincial Key Lab of Dark Tea and Jin-Hua, School of Materials and Chemical Engineering, Hunan City University, Yiyang 413000, China
| | - Zhanjun Liu
- Hunan Provincial Key Lab of Dark Tea and Jin-Hua, School of Materials and Chemical Engineering, Hunan City University, Yiyang 413000, China
| | - Xiaohong Zhou
- Hunan Provincial Key Lab of Dark Tea and Jin-Hua, School of Materials and Chemical Engineering, Hunan City University, Yiyang 413000, China
| | - Rong Liu
- Hunan Provincial Key Lab of Dark Tea and Jin-Hua, School of Materials and Chemical Engineering, Hunan City University, Yiyang 413000, China
| | - Shiquan Liu
- Hunan Provincial Key Lab of Dark Tea and Jin-Hua, School of Materials and Chemical Engineering, Hunan City University, Yiyang 413000, China
| | - Yan Deng
- Hunan Key Laboratory of Biomedical Nanomaterials and Devices, Hunan University of Technology, Zhuzhou 412007, China
| | - Song Li
- Hunan Key Laboratory of Biomedical Nanomaterials and Devices, Hunan University of Technology, Zhuzhou 412007, China
| | - Hui Chen
- Hunan Key Laboratory of Biomedical Nanomaterials and Devices, Hunan University of Technology, Zhuzhou 412007, China
| | - Zhu Chen
- Hunan Key Laboratory of Biomedical Nanomaterials and Devices, Hunan University of Technology, Zhuzhou 412007, China
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8
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Wu Q, Liu C, Liu Y, Cui C, Ge J, Tan W. Multibranched Linear DNA-Controlled Assembly of Silver Nanoclusters and Their Applications in Aptamer-Based Cell Recognition. ACS APPLIED MATERIALS & INTERFACES 2022; 14:14953-14960. [PMID: 35344322 DOI: 10.1021/acsami.1c24547] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/14/2023]
Abstract
DNA-templated silver nanoclusters (DNA-AgNCs) are promising fluorescent materials and have been used in cancer diagnosis. Although many different DNA-AgNC applications have been realized, most of them rely on individual DNA-AgNCs or assembled DNA-AgNCs with limited recognition abilities, resulting in low detection sensitivity or off-target effects, in turn, hindering the performance of DNA-AgNCs in cancer cell recognition. As a solution, we assembled DNA-AgNCs by a multibranched linear (MBL) DNA structure formed through a trigger-initiated hybridization chain reaction (HCR) regarding the natural compatibility of DNA-AgNCs with DNA programmability and the advantages of DNA assembly in incorporating repetitive and functional moieties into one structure. By the specific modification of the trigger, MBL-AgNCs tethered with the targeting aptamer and partially hybridized duplex, which works as a component of DNA logic platform relying on the combination of cascade strand displacement reaction and specific recognition ability of aptamers, were obtained, respectively. DNA-AgNCs assembled by the aptamer-tethered MBL structure exhibited about 20-fold enhanced detection sensitivity in recognizing cancer cells compared to individual aptamer-tethered DNA-AgNCs. DNA-AgNCs assembled by the duplex-attached MBL exhibited logic performance in analyzing dual cell surface receptors with the assistance of "AND" logic platform, thus identifying cancer cells with high sensitivity and resolution. The facile conjugation of the MBL structure with different functional DNA structures makes it an ideal platform to assemble DNA-AgNCs used for aptamer-based cell recognition, thus broadening the potential applications of DNA-AgNCs.
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Affiliation(s)
- Qiong Wu
- Center for Research at Bio/Nano Interface, Department of Chemistry and Department of Physiology and Functional Genomics, UF Health Cancer Center, UF Genetics Institute and McKnight Brain Institute, University of Florida, Gainesville, Florida 32611-7200, United States
| | - Chengcheng Liu
- Center for Research at Bio/Nano Interface, Department of Chemistry and Department of Physiology and Functional Genomics, UF Health Cancer Center, UF Genetics Institute and McKnight Brain Institute, University of Florida, Gainesville, Florida 32611-7200, United States
| | - Yuan Liu
- Center for Research at Bio/Nano Interface, Department of Chemistry and Department of Physiology and Functional Genomics, UF Health Cancer Center, UF Genetics Institute and McKnight Brain Institute, University of Florida, Gainesville, Florida 32611-7200, United States
- The Cancer Hospital of the University of Chinese Academy of Sciences (Zhejiang Cancer Hospital), Hangzhou Institute of Medicine (HIM), Chinese Academy of Sciences, Hangzhou, Zhejiang 310022, China
| | - Cheng Cui
- Molecular Science and Biomedicine Laboratory (MBL), State Key Laboratory of Chemo/Biosensing and Chemometrics, College of Chemistry and Chemical Engineering, College of Biology, Aptamer Engineering Center of Hunan Province, Hunan University, Changsha 410082, China
| | - Jia Ge
- College of Chemistry and Molecular Engineering, Zhengzhou University, Zhengzhou 450001, China
| | - Weihong Tan
- Center for Research at Bio/Nano Interface, Department of Chemistry and Department of Physiology and Functional Genomics, UF Health Cancer Center, UF Genetics Institute and McKnight Brain Institute, University of Florida, Gainesville, Florida 32611-7200, United States
- Molecular Science and Biomedicine Laboratory (MBL), State Key Laboratory of Chemo/Biosensing and Chemometrics, College of Chemistry and Chemical Engineering, College of Biology, Aptamer Engineering Center of Hunan Province, Hunan University, Changsha 410082, China
- The Cancer Hospital of the University of Chinese Academy of Sciences (Zhejiang Cancer Hospital), Hangzhou Institute of Medicine (HIM), Chinese Academy of Sciences, Hangzhou, Zhejiang 310022, China
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9
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Wu Q, Liu C, Cui C, Li L, Yang L, Liu Y, Safari Yazd H, Xu S, Li X, Chen Z, Tan W. Plasmon Coupling in DNA-Assembled Silver Nanoclusters. J Am Chem Soc 2021; 143:14573-14580. [PMID: 34464111 DOI: 10.1021/jacs.1c04949] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Quantum-size metal clusters with multiple delocalized electrons could support collective plasmon excitation, and thus, theoretically, coupling of plasmons in the few-atom limit might exist between assembled metal clusters, while currently few experimental observations about this phenomenon have been reported. Here we examined the optical absorption of DNA-templated Ag nanoclusters (DNA-AgNCs) assembled through DNA hybridization and found their absorption peaks were sensitive to the assembled distances, which share common characteristics with classical plasmon coupling. Dipolar charge distribution, multiple transition contributed optical absorption, and strongly enhanced electric field simulated by time-dependent density functional theory (TDDFT) indicated the origin of the absorption of individual DNA-AgNCs is a plasmon. The consistency of the peak-shifting trend between experimental and simulation results for assembled DNA-AgNCs suggested the possible presence of plasmon coupling. Our data imply the possibility for quantum-size structures to support plasmon coupling and also show that DNA-AgNCs possess the potential to be promising materials for construction of plasmon-coupling devices with ultrasmall size, site-specific and stoichiometric binding abilities, and biocompatibility.
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Affiliation(s)
- Qiong Wu
- Center for Research at Bio/Nano Interface, Department of Chemistry and Department of Physiology and Functional Genomics, UF Health Cancer Center, UF Genetics Institute and McKnight Brain Institute, University of Florida, Gainesville, Florida 32611-7200, United States
| | - Chengcheng Liu
- Center for Research at Bio/Nano Interface, Department of Chemistry and Department of Physiology and Functional Genomics, UF Health Cancer Center, UF Genetics Institute and McKnight Brain Institute, University of Florida, Gainesville, Florida 32611-7200, United States
| | - Cheng Cui
- Center for Research at Bio/Nano Interface, Department of Chemistry and Department of Physiology and Functional Genomics, UF Health Cancer Center, UF Genetics Institute and McKnight Brain Institute, University of Florida, Gainesville, Florida 32611-7200, United States.,Molecular Science and Biomedicine Laboratory (MBL), State Key Laboratory of Chemo/Biosensing and Chemometrics, College of Chemistry and Chemical Engineering, College of Biology, Aptamer Engineering Center of Hunan Province, Hunan University, Changsha, Hunan 410082, China
| | - Long Li
- The Cancer Hospital of the University of Chinese Academy of Sciences (Zhejiang Cancer Hospital), Institute of Basic Medicine and Cancer (IBMC), Chinese Academy of Sciences, Hangzhou, Zhejiang 310022, China.,Center for Research at Bio/Nano Interface, Department of Chemistry and Department of Physiology and Functional Genomics, UF Health Cancer Center, UF Genetics Institute and McKnight Brain Institute, University of Florida, Gainesville, Florida 32611-7200, United States
| | - Lu Yang
- Center for Research at Bio/Nano Interface, Department of Chemistry and Department of Physiology and Functional Genomics, UF Health Cancer Center, UF Genetics Institute and McKnight Brain Institute, University of Florida, Gainesville, Florida 32611-7200, United States
| | - Yuan Liu
- The Cancer Hospital of the University of Chinese Academy of Sciences (Zhejiang Cancer Hospital), Institute of Basic Medicine and Cancer (IBMC), Chinese Academy of Sciences, Hangzhou, Zhejiang 310022, China.,Center for Research at Bio/Nano Interface, Department of Chemistry and Department of Physiology and Functional Genomics, UF Health Cancer Center, UF Genetics Institute and McKnight Brain Institute, University of Florida, Gainesville, Florida 32611-7200, United States
| | - Hoda Safari Yazd
- Center for Research at Bio/Nano Interface, Department of Chemistry and Department of Physiology and Functional Genomics, UF Health Cancer Center, UF Genetics Institute and McKnight Brain Institute, University of Florida, Gainesville, Florida 32611-7200, United States
| | - Shujuan Xu
- Center for Research at Bio/Nano Interface, Department of Chemistry and Department of Physiology and Functional Genomics, UF Health Cancer Center, UF Genetics Institute and McKnight Brain Institute, University of Florida, Gainesville, Florida 32611-7200, United States
| | - Xiang Li
- Center for Research at Bio/Nano Interface, Department of Chemistry and Department of Physiology and Functional Genomics, UF Health Cancer Center, UF Genetics Institute and McKnight Brain Institute, University of Florida, Gainesville, Florida 32611-7200, United States
| | - Zhuo Chen
- Molecular Science and Biomedicine Laboratory (MBL), State Key Laboratory of Chemo/Biosensing and Chemometrics, College of Chemistry and Chemical Engineering, College of Biology, Aptamer Engineering Center of Hunan Province, Hunan University, Changsha, Hunan 410082, China
| | - Weihong Tan
- The Cancer Hospital of the University of Chinese Academy of Sciences (Zhejiang Cancer Hospital), Institute of Basic Medicine and Cancer (IBMC), Chinese Academy of Sciences, Hangzhou, Zhejiang 310022, China.,Center for Research at Bio/Nano Interface, Department of Chemistry and Department of Physiology and Functional Genomics, UF Health Cancer Center, UF Genetics Institute and McKnight Brain Institute, University of Florida, Gainesville, Florida 32611-7200, United States.,Molecular Science and Biomedicine Laboratory (MBL), State Key Laboratory of Chemo/Biosensing and Chemometrics, College of Chemistry and Chemical Engineering, College of Biology, Aptamer Engineering Center of Hunan Province, Hunan University, Changsha, Hunan 410082, China.,Institute of Molecular Medicine (IMM), Renji Hospital, Shanghai Jiao Tong University School of Medicine, and College of Chemistry and Chemical Engineering, Shanghai Jiao Tong University, Shanghai 200240, China
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10
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Zhang Y, He C, de La Harpe K, Goodwin PM, Petty JT, Kohler B. A single nucleobase tunes nonradiative decay in a DNA-bound silver cluster. J Chem Phys 2021; 155:094305. [PMID: 34496579 DOI: 10.1063/5.0056836] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023] Open
Abstract
DNA strands are polymeric ligands that both protect and tune molecular-sized silver cluster chromophores. We studied single-stranded DNA C4AC4TC3XT4 with X = guanosine and inosine that form a green fluorescent Ag10 6+ cluster, but these two hosts are distinguished by their binding sites and the brightness of their Ag10 6+ adducts. The nucleobase subunits in these oligomers collectively coordinate this cluster, and fs time-resolved infrared spectra previously identified one point of contact between the C2-NH2 of the X = guanosine, an interaction that is precluded for inosine. Furthermore, this single nucleobase controls the cluster fluorescence as the X = guanosine complex is ∼2.5× dimmer. We discuss the electronic relaxation in these two complexes using transient absorption spectroscopy in the time window 200 fs-400 µs. Three prominent features emerged: a ground state bleach, an excited state absorption, and a stimulated emission. Stimulated emission at the earliest delay time (200 fs) suggests that the emissive state is populated promptly following photoexcitation. Concurrently, the excited state decays and the ground state recovers, and these changes are ∼2× faster for the X = guanosine compared to the X = inosine cluster, paralleling their brightness difference. In contrast to similar radiative decay rates, the nonradiative decay rate is 7× higher with the X = guanosine vs inosine strand. A minor decay channel via a dark state is discussed. The possible correlation between the nonradiative decay and selective coordination with the X = guanosine/inosine suggests that specific nucleobase subunits within a DNA strand can modulate cluster-ligand interactions and, in turn, cluster brightness.
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Affiliation(s)
- Yuyuan Zhang
- Department of Chemistry and Biochemistry, The Ohio State University, 100 West 18th Avenue, Columbus, Ohio 43210, USA
| | - Chen He
- Department of Chemistry, Furman University, Greenville, South Carolina 29613, USA
| | - Kimberly de La Harpe
- Department of Physics, United States Air Force Academy, U.S. Air Force Academy, Colorado 80840, USA
| | - Peter M Goodwin
- Center for Integrated Nanotechnologies, Los Alamos National Laboratory, Mail Stop K771, Los Alamos, New Mexico 87545, USA
| | - Jeffrey T Petty
- Department of Chemistry, Furman University, Greenville, South Carolina 29613, USA
| | - Bern Kohler
- Department of Chemistry and Biochemistry, The Ohio State University, 100 West 18th Avenue, Columbus, Ohio 43210, USA
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11
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Petty JT, Carnahan S, Kim D, Lewis D. Long-lived Ag 10 6+ luminescence and a split DNA scaffold. J Chem Phys 2021; 154:244302. [PMID: 34241360 DOI: 10.1063/5.0056214] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Molecular silver clusters emit across the visible to near-infrared, and specific chromophores can be formed using DNA strands. We study C4AC4TC3G that selectively coordinates and encapsulates Ag10 6+, and this chromophore has two distinct electronic transitions. The green emission is strong and prompt with ϕ = 18% and τ = 1.25 ns, and the near-infrared luminescence is weaker, slower with τ = 50 µs, and is partly quenched by oxygen, suggesting phosphorescence. This lifetime can be modulated by the DNA host, and we consider two derivatives of C4AC4TC3G with similar sequences but distinct structures. In one variant, thymine was excised to create an abasic gap in an otherwise intact strand. In the other, the covalent phosphate linkage was removed to split the DNA scaffold into two fragments. In relation to the contiguous strands, the broken template speeds the luminescence decay by twofold, and this difference may be due to greater DNA flexibility. These modifications suggest that a DNA can be structurally tuned to modulate metastable electronic states in its silver cluster adducts.
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Affiliation(s)
- Jeffrey T Petty
- Department of Chemistry, Furman University, Greenville, South Carolina 29613, USA
| | - Savannah Carnahan
- Department of Chemistry, Furman University, Greenville, South Carolina 29613, USA
| | - Dahye Kim
- Department of Chemistry, Furman University, Greenville, South Carolina 29613, USA
| | - David Lewis
- Department of Chemistry, Furman University, Greenville, South Carolina 29613, USA
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12
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Gonzàlez-Rosell A, Cerretani C, Mastracco P, Vosch T, Copp SM. Structure and luminescence of DNA-templated silver clusters. NANOSCALE ADVANCES 2021; 3:1230-1260. [PMID: 36132866 PMCID: PMC9417461 DOI: 10.1039/d0na01005g] [Citation(s) in RCA: 40] [Impact Index Per Article: 13.3] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/01/2020] [Accepted: 01/21/2021] [Indexed: 05/05/2023]
Abstract
DNA serves as a versatile template for few-atom silver clusters and their organized self-assembly. These clusters possess unique structural and photophysical properties that are programmed into the DNA template sequence, resulting in a rich palette of fluorophores which hold promise as chemical and biomolecular sensors, biolabels, and nanophotonic elements. Here, we review recent advances in the fundamental understanding of DNA-templated silver clusters (Ag N -DNAs), including the role played by the silver-mediated DNA complexes which are synthetic precursors to Ag N -DNAs, structure-property relations of Ag N -DNAs, and the excited state dynamics leading to fluorescence in these clusters. We also summarize the current understanding of how DNA sequence selects the properties of Ag N -DNAs and how sequence can be harnessed for informed design and for ordered multi-cluster assembly. To catalyze future research, we end with a discussion of several opportunities and challenges, both fundamental and applied, for the Ag N -DNA research community. A comprehensive fundamental understanding of this class of metal cluster fluorophores can provide the basis for rational design and for advancement of their applications in fluorescence-based sensing, biosciences, nanophotonics, and catalysis.
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Affiliation(s)
- Anna Gonzàlez-Rosell
- Department of Materials Science and Engineering, University of California Irvine California 92697-2585 USA
| | - Cecilia Cerretani
- Nanoscience Center and Department of Chemistry, University of Copenhagen, Universitetsparken 5 2100 Copenhagen Denmark
| | - Peter Mastracco
- Department of Materials Science and Engineering, University of California Irvine California 92697-2585 USA
| | - Tom Vosch
- Nanoscience Center and Department of Chemistry, University of Copenhagen, Universitetsparken 5 2100 Copenhagen Denmark
| | - Stacy M Copp
- Department of Materials Science and Engineering, University of California Irvine California 92697-2585 USA
- Department of Physics and Astronomy, University of California Irvine California 92697-4575 USA
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13
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de la Hoz A, Navarro A, Aviñó A, Eritja R, Gargallo R. Studies on the interactions of Ag(i) with DNA and their implication on the DNA-templated synthesis of silver nanoclusters and on the interaction with complementary DNA and RNA sequences. RSC Adv 2021; 11:9029-9042. [PMID: 35423401 PMCID: PMC8695332 DOI: 10.1039/d1ra00194a] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2021] [Accepted: 02/15/2021] [Indexed: 12/22/2022] Open
Abstract
Silver nanoclusters (AgNCs) prepared by the reduction of silver ions in the presence of DNA oligonucleotides have attracted great interest as potential diagnostic tools for their tunable and high fluorescent properties. In this work, three DNA sequences that consist of a 12-nucleotide long probe sequence at the 5′-end linked to the complementary sequence to three miRNAs are studied. First, the interaction of these sequences with Ag(i) was characterized by means of circular dichroism spectroscopy. By applying multivariate methods to the analysis of spectroscopic data, two complexes with different Ag(i) : DNA ratios were resolved. Secondly, the impact of several experimental variables, such as temperature, borohydride concentration and reaction time, on the formation of AgNCs templated by these three sequences was studied. Finally, the fluorescence properties of the duplexes formed by DNA probes with complementary DNA or miRNA sequences were studied. The results presented here highlight the role of the secondary structure adopted by the DNA probe on the fluorescence properties of DNA-stabilized AgNCs which, in turn, affect the development of methods for miRNA detection. Variables affecting the fluorescent properties of DNA-stabilized silver nanoclusters are studied. The secondary structure of the AgNC-stabilizing DNA sequence dramatically affects the analytical signal behind the hybridization reaction.![]()
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Affiliation(s)
- Alejandra de la Hoz
- Dept. of Chemical Engineering and Analytical Chemistry, University of Barcelona Marti i Franquès 1 E-08028 Barcelona Spain
| | - Alba Navarro
- Dept. of Chemical Engineering and Analytical Chemistry, University of Barcelona Marti i Franquès 1 E-08028 Barcelona Spain
| | - Anna Aviñó
- Institute for Advanced Chemistry of Catalonia (IQAC-CSIC), CIBER-BBN Jordi Girona 18-26 E-08034 Barcelona Spain
| | - Ramon Eritja
- Institute for Advanced Chemistry of Catalonia (IQAC-CSIC), CIBER-BBN Jordi Girona 18-26 E-08034 Barcelona Spain
| | - Raimundo Gargallo
- Dept. of Chemical Engineering and Analytical Chemistry, University of Barcelona Marti i Franquès 1 E-08028 Barcelona Spain
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14
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Ma J, Niu H, Gu S. The spatial organization of trace silver atoms on a DNA template. RSC Adv 2020; 11:1153-1163. [PMID: 35423706 PMCID: PMC8693506 DOI: 10.1039/d0ra08066g] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2020] [Accepted: 12/07/2020] [Indexed: 02/06/2023] Open
Abstract
DNA with programmable information can be used to encode the spatial organization of silver atoms. Based on the primary structures of a DNA template containing a controllable base arrangement and number, the surrounding environment and cluster together can induce the folding of the DNA template into an appropriate secondary structure for forming AgNCs with different fluorescence emissions, such as i-motif, G-quadruplex, dimeric template, triplex, monomeric or dimeric C-loop, emitter pair, and G-enhancer/template conjugate. Stimuli can induce the dynamic structural transformation of the DNA template with a recognition site for favourably or unfavourably forming AgNCs, along with varied fluorescence intensities and colours. The array of several or more of the same and different clusters can be performed on simple and complex nanostructures, while maintaining their original properties. By sorting out this review, we systematically conclude the link between the performance of AgNCs and the secondary structure of the DNA template, and summarize the precise arrangement of nanoclusters on DNA nanotechnology. This clear review on the origin and controllability of AgNCs based on the secondary structure of the DNA template is beneficial for exploring the new probe and optical devices.
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Affiliation(s)
- Jinliang Ma
- College of Food and Bioengineering, Henan University of Science and Technology Luoyang Henan 471023 China
- Institute of Molecular Medicine, Renji Hospital, School of Medicine, Shanghai Jiao Tong University Shanghai 200127 China
| | - Huawei Niu
- College of Food and Bioengineering, Henan University of Science and Technology Luoyang Henan 471023 China
| | - Shaobin Gu
- College of Food and Bioengineering, Henan University of Science and Technology Luoyang Henan 471023 China
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15
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Geczy R, Christensen NJ, Rasmussen KK, Kálomista I, Tiwari MK, Shah P, Yang SW, Bjerrum MJ, Thulstrup PW. Formation and Structure of Fluorescent Silver Nanoclusters at Interfacial Binding Sites Facilitating Oligomerization of DNA Hairpins. Angew Chem Int Ed Engl 2020. [DOI: 10.1002/ange.202005102] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Affiliation(s)
- Reka Geczy
- Department of Chemistry University of Copenhagen Universitetsparken 5 2100 Copenhagen Denmark
| | - Niels Johan Christensen
- Department of Chemistry University of Copenhagen Thorvaldsensvej 40 1871 Frederiksberg Denmark
| | - Kim K. Rasmussen
- Department of Chemistry University of Copenhagen Universitetsparken 5 2100 Copenhagen Denmark
| | - Ildikó Kálomista
- Department of Chemistry University of Copenhagen Universitetsparken 5 2100 Copenhagen Denmark
| | - Manish K. Tiwari
- Department of Chemistry University of Copenhagen Universitetsparken 5 2100 Copenhagen Denmark
| | - Pratik Shah
- Department of Systems Biology Institute of Life Science and Biotechnology Yonsei University Seoul 03722 Korea
| | - Seong Wook Yang
- Department of Systems Biology Institute of Life Science and Biotechnology Yonsei University Seoul 03722 Korea
| | - Morten J. Bjerrum
- Department of Chemistry University of Copenhagen Universitetsparken 5 2100 Copenhagen Denmark
| | - Peter W. Thulstrup
- Department of Chemistry University of Copenhagen Universitetsparken 5 2100 Copenhagen Denmark
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16
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Geczy R, Christensen NJ, Rasmussen KK, Kálomista I, Tiwari MK, Shah P, Yang SW, Bjerrum MJ, Thulstrup PW. Formation and Structure of Fluorescent Silver Nanoclusters at Interfacial Binding Sites Facilitating Oligomerization of DNA Hairpins. Angew Chem Int Ed Engl 2020; 59:16091-16097. [DOI: 10.1002/anie.202005102] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2020] [Revised: 05/18/2020] [Indexed: 12/14/2022]
Affiliation(s)
- Reka Geczy
- Department of Chemistry University of Copenhagen Universitetsparken 5 2100 Copenhagen Denmark
| | - Niels Johan Christensen
- Department of Chemistry University of Copenhagen Thorvaldsensvej 40 1871 Frederiksberg Denmark
| | - Kim K. Rasmussen
- Department of Chemistry University of Copenhagen Universitetsparken 5 2100 Copenhagen Denmark
| | - Ildikó Kálomista
- Department of Chemistry University of Copenhagen Universitetsparken 5 2100 Copenhagen Denmark
| | - Manish K. Tiwari
- Department of Chemistry University of Copenhagen Universitetsparken 5 2100 Copenhagen Denmark
| | - Pratik Shah
- Department of Systems Biology Institute of Life Science and Biotechnology Yonsei University Seoul 03722 Korea
| | - Seong Wook Yang
- Department of Systems Biology Institute of Life Science and Biotechnology Yonsei University Seoul 03722 Korea
| | - Morten J. Bjerrum
- Department of Chemistry University of Copenhagen Universitetsparken 5 2100 Copenhagen Denmark
| | - Peter W. Thulstrup
- Department of Chemistry University of Copenhagen Universitetsparken 5 2100 Copenhagen Denmark
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17
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Label-free detection of microRNA: two-stage signal enhancement with hairpin assisted cascade isothermal amplification and light-up DNA-silver nanoclusters. Mikrochim Acta 2020; 187:141. [PMID: 31965324 DOI: 10.1007/s00604-019-4094-1] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2019] [Accepted: 12/22/2019] [Indexed: 12/19/2022]
Abstract
A method is described for the determination of microRNAs via two-stage signal enhancement. This is attained by combining hairpin (HP) assisted cascade isothermal amplification with light-up DNA-Ag nanoclusters. A rationally designed dual-functional HP is used, and microRNA-21 is chosen as a model analyte. At the first stage, upon the hybridization of the microRNA-21 with HP, microRNA recycling via polymerase-displacement reaction and a circulative nicking-replication process are achieved. This generates numerous G-abundant overhang DNA sequences. In the second stage, the above-released G-abundant overhang DNA sequences hybridize with the dark green Ag NCs, and this results in the appearance of bright red fluorescence. Thanks to the two signal enhancement processes, a linear dependence between the fluorescence intensity at 616 nm and the concentration of microRNA-21 is obtained in the range from 1 pM to 20 pM with a detection limit of 0.7 pM. The strategy clearly discriminates between perfectly-matched and mismatched targets. The method was applied to the determination of microRNA-21 in a spiked serum sample. Graphical abstractSchematic representation of microRNA detection by integrating hairpin assisted cascade isothermal amplification with light-up DNA Ag nanoclusters. With microRNA, G-abundant overhang DNA sequences from amplification reaction hybridize with dark green Ag nanoclusters to produce a concentration-dependent bright red fluorescence.
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18
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Blevins MS, Kim D, Crittenden CM, Hong S, Yeh HC, Petty JT, Brodbelt JS. Footprints of Nanoscale DNA-Silver Cluster Chromophores via Activated-Electron Photodetachment Mass Spectrometry. ACS NANO 2019; 13:14070-14079. [PMID: 31755695 PMCID: PMC7047740 DOI: 10.1021/acsnano.9b06470] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/07/2023]
Abstract
DNA-templated silver clusters (AgC) are fluorescent probes and biosensors whose electronic spectra can be tuned by their DNA hosts. However, the underlying rules that relate DNA sequence and structure to DNA-AgC fluorescence and photophysics are largely empirical. Here, we employ 193 nm activated electron photodetachment (a-EPD) mass spectrometry as a hybrid MS3 approach to gain structural insight into these nanoscale chromophores. Two DNA-AgC systems are investigated with a 20 nt single-stranded DNA (ssDNA) and a 28 nt hybrid hairpin/single-stranded DNA (hpDNA). Both oligonucleotides template Ag10 clusters, but the two complexes are distinct chromophores: the former has a violet absorption at 400 nm with no observable emission, while the latter has a blue-green absorption at 490 nm with strong green emission at 550 nm. Via identification of both apo and holo (AgC-containing) sequence ions generated upon a-EPD and mapping areas of sequence dropout, specific DNA regions that encapsulate the AgC are assigned and attributed to the coordination with the DNA nucleobases. These a-EPD footprints are distinct for the two complexes. The ssDNA contacts the cluster via four nucleobases (CCTT) in the central region of the strand, whereas the hpDNA coordinates the cluster via 13 nucleobases (TTCCCGCCTTTTG) in the double-stranded region of the hairpin. This difference is consistent with prior X-ray scattering spectra and suggests that the clusters can adapt to different DNA hosts. More importantly, the a-EPD footprints directly identify the nucleobases that are in direct contact with the AgC. As these contacting nucleobases can tune the electronic structures of the Ag core and protect the AgC from collisional quenching in solution, understanding the DNA-silver contacts within these complexes will facilitate future biosensor designs.
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Affiliation(s)
- Molly S. Blevins
- Department of Chemistry, University of Texas at Austin, Austin, Texas 78712, United States
| | - Dahye Kim
- Department of Chemistry, Furman University, Greenville, South Carolina 29613, United States
| | | | - Soonwoo Hong
- Department of Biomedical Engineering, University of Texas at Austin, Austin, Texas 78712, United States
| | - Hsin-Chih Yeh
- Department of Biomedical Engineering, University of Texas at Austin, Austin, Texas 78712, United States
- Texas Materials Institute, University of Texas at Austin, Austin, Texas 78712, United States
| | - Jeffrey T. Petty
- Department of Chemistry, Furman University, Greenville, South Carolina 29613, United States
| | - Jennifer S. Brodbelt
- Department of Chemistry, University of Texas at Austin, Austin, Texas 78712, United States
- Corresponding Author:.
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19
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Cerretani C, Vosch T. Switchable Dual-Emissive DNA-Stabilized Silver Nanoclusters. ACS OMEGA 2019; 4:7895-7902. [PMID: 31459877 PMCID: PMC6693819 DOI: 10.1021/acsomega.9b00614] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/05/2019] [Accepted: 04/19/2019] [Indexed: 05/10/2023]
Abstract
We investigated an ss-DNA sequence that can stabilize a red- and a green-emissive silver nanocluster (DNA-AgNC). These two emitters can convert between each other in a reversible way. The change from red- to green-emitting DNA-AgNCs can be triggered by the addition of H2O2, while the opposite conversion can be achieved by the addition of NaBH4. Besides demonstrating the switching between red- and green-emissive DNA-AgNCs and determining the recoverability, we fully characterized the photophysical properties, such as steady-state emission, quantum yield, fluorescence lifetime, and anisotropy of the two emissive species. Understanding the mechanism behind the remarkable conversion between the two emitters could lead to the development of a new range of DNA-AgNC-based ratiometric sensors.
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20
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Chen YA, Vu HT, Liu YL, Chen YI, Nguyen TD, Kuo YA, Hong S, Chen YA, Carnahan S, Petty JT, Yeh HC. Improving NanoCluster Beacon performance by blocking the unlabeled NC probes. Chem Commun (Camb) 2019; 55:462-465. [PMID: 30547174 DOI: 10.1039/c8cc08291j] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
While NanoCluster Beacon (NCB) is a versatile molecular probe, it suffers from a low target-specific signal issue due to impurities. Here we show that adding a "blocker" strand to the reaction can effectively block the nonfunctional probes and enhance the target-specific signal by 14 fold at a 0.1 target/probe ratio.
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Affiliation(s)
- Yu-An Chen
- Department of Biomedical Engineering, University of Texas at Austin, Austin, Texas 78712, USA.
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21
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Shah P, Choi SW, Nagda R, Geczy R, Cho SK, Bhang YJ, Kim TH, Song TY, Lee PH, Kang JH, Thulstrup PW, Bjerrum MJ, Jung IL, Yang SW. The structural shift of a DNA template between a hairpin and a dimer tunes the emission color of DNA-templated AgNCs. NANOSCALE 2018; 10:20717-20722. [PMID: 30398269 DOI: 10.1039/c8nr06186f] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
The scaffolding DNA sequence and the size of silver nanoclusters (AgNCs), confined in a DNA template are the key parameters in determining the fluorescent properties of DNA-stabilized silver nanoclusters (DNA/AgNCs). In addition, we suggest here that the structural shift of a DNA hairpin-dimer is as important as the DNA sequence in determining the emission wavelength of DNA/AgNCs. Furthermore, we show that the structural shift post AgNC formation can be triggered by incubation time and pre-AgNC formation under salt conditions. As an important factor in predicting the emission properties of DNA/AgNCs, the modulation of DNA secondary structures with either sequence changes or ionic conditions can be applied for the dual-color detection system of a target molecule. Particularly, the dual-color detection method may increase the reliability of DNA/AgNC sensors for miRNAs.
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Affiliation(s)
- Pratik Shah
- Department of Systems Biology, College of Life Science and Biotechnology, Yonsei University, Korea.
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22
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Ang Y, Woon W, Yung LYL. The role of spacer sequence in modulating turn-on fluorescence of DNA-templated silver nanoclusters. Nucleic Acids Res 2018; 46:6974-6982. [PMID: 29982768 PMCID: PMC6101541 DOI: 10.1093/nar/gky521] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2018] [Revised: 05/18/2018] [Accepted: 06/09/2018] [Indexed: 12/18/2022] Open
Abstract
Guanine activation of fluorescence in DNA templated silver nanoclusters (AgNCs) is an interesting physical phenomenon which has yet to be fully understood to date. While the individual role of cytosine and guanine has been established, there is still a knowledge gap on how the AgNC-DNA system switches from dark to bright state. Here, we present evidence on the universal role of the DNA spacer sequence in physically separating two Ag+-binding cytosine sites to maintain the dark state while holding them together for structural re-organization by the guanine-rich strand to activate the bright state. The extent of turn-on signal could be modulated by adjusting the spacer length and composition. The ATATA spacer sequence was found to have negligible dark state fluorescence and a turn-on effect of 2440-fold, which was almost five times of the highest factor reported to date.
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Affiliation(s)
- Yan Shan Ang
- Department of Chemical & Biomolecular Engineering, National University of Singapore, 4 Engineering Drive 4, Singapore 117585
| | - Wei Wen Elvin Woon
- Department of Chemical & Biomolecular Engineering, National University of Singapore, 4 Engineering Drive 4, Singapore 117585
| | - Lin-Yue Lanry Yung
- Department of Chemical & Biomolecular Engineering, National University of Singapore, 4 Engineering Drive 4, Singapore 117585
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23
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Chen Z, Liu C, Cao F, Ren J, Qu X. DNA metallization: principles, methods, structures, and applications. Chem Soc Rev 2018; 47:4017-4072. [DOI: 10.1039/c8cs00011e] [Citation(s) in RCA: 114] [Impact Index Per Article: 19.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
This review summarizes the research activities on DNA metallization since the concept was first proposed in 1998, covering the principles, methods, structures, and applications.
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Affiliation(s)
- Zhaowei Chen
- Laboratory of Chemical Biology and State Key Laboratory of Rare Earth Resources Utilization
- Changchun Institute of Applied Chemistry
- Chinese Academy of Science
- Changchun
- P. R. China
| | - Chaoqun Liu
- Laboratory of Chemical Biology and State Key Laboratory of Rare Earth Resources Utilization
- Changchun Institute of Applied Chemistry
- Chinese Academy of Science
- Changchun
- P. R. China
| | - Fangfang Cao
- Laboratory of Chemical Biology and State Key Laboratory of Rare Earth Resources Utilization
- Changchun Institute of Applied Chemistry
- Chinese Academy of Science
- Changchun
- P. R. China
| | - Jinsong Ren
- Laboratory of Chemical Biology and State Key Laboratory of Rare Earth Resources Utilization
- Changchun Institute of Applied Chemistry
- Chinese Academy of Science
- Changchun
- P. R. China
| | - Xiaogang Qu
- Laboratory of Chemical Biology and State Key Laboratory of Rare Earth Resources Utilization
- Changchun Institute of Applied Chemistry
- Chinese Academy of Science
- Changchun
- P. R. China
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24
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Jana J, Aditya T, Negishi Y, Pal T. Solvent Polarity-Dependent Behavior of Aliphatic Thiols and Amines toward Intriguingly Fluorescent AuAgGSH Assembly. ACS OMEGA 2017; 2:8086-8098. [PMID: 31457357 PMCID: PMC6645147 DOI: 10.1021/acsomega.7b01560] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 10/16/2017] [Accepted: 11/02/2017] [Indexed: 06/10/2023]
Abstract
Highly stable fluorescent glutathione (GSH)-protected AuAg assembly has been synthesized in water under UV irradiation. The assembly is composed of small Ag2/Ag3 clusters. These clusters gain stability through synergistic interaction with Au(I) present within the assembly. This makes the overall assembly fluorescent. Here, GSH acts as a reducing as well as stabilizing agent. The assembly is so robust that it can be vacuum-dried to solid particles. The as-obtained solid is dispersible in nonaqueous solvents. The interaction between solvent and the assembly provides stability to the assembly, and the assembly shows fluorescence. It is interesting to see that the behavior of long-chain aliphatic thiols or amines toward the fluorescent assembly is altogether a different phenomenon in aqueous and nonaqueous mediums. The assembly gets ruptured in water due to direct interaction with long-chain thiols or amines, whereas in nonaqueous medium, solvation of added thiols or amines becomes pronounced, which hinders the interaction of solvent with the assembly. However, the fluorescence of the assembly is always quenched with thiols or amines no matter what the solvent medium is. In aqueous medium, the fluorescence quenching by aliphatic thiol or amine becomes pronounced with successive decrease in their chain length, whereas in nonaqueous medium, the trend is just reversed with chain length. The reasons behind such an interesting reversal of fluorescence quenching in aqueous and nonaqueous solvents have been discussed explicitly. Again, in organic solvents, thiol or amine-induced quenched fluorescence is selectively recovered by Pb(II) ion without any alteration of excitation and emission maxima. This phenomenon is not observed in water because of the ruptured fluorescent assembly. The fluorescence recovery by Pb(II) and unaltered emission peak only in nonaqueous solvent unequivocally prove the engagement of Pb(II) with thiols or amines, which in turn revert the original solvent-supported stabilization of the assembly.
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Affiliation(s)
- Jayasmita Jana
- Department
of Chemistry, Indian Institute of Technology, Kharagpur 721302, India
| | - Teresa Aditya
- Department
of Chemistry, Indian Institute of Technology, Kharagpur 721302, India
| | - Yuichi Negishi
- Department
of Applied Chemistry, Tokyo University of
Science, Tokyo 1628601, Japan
| | - Tarasankar Pal
- Department
of Chemistry, Indian Institute of Technology, Kharagpur 721302, India
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25
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Ultrafast coherence transfer in DNA-templated silver nanoclusters. Nat Commun 2017; 8:15577. [PMID: 28548085 PMCID: PMC5493596 DOI: 10.1038/ncomms15577] [Citation(s) in RCA: 39] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2016] [Accepted: 04/06/2017] [Indexed: 12/16/2022] Open
Abstract
DNA-templated silver nanoclusters of a few tens of atoms or less have come into prominence over the last several years due to very strong absorption and efficient emission. Applications in microscopy and sensing have already been realized, however little is known about the excited-state structure and dynamics in these clusters. Here we report on a multidimensional spectroscopy investigation of the energy-level structure and the early-time relaxation cascade, which eventually results in the population of an emitting state. We find that the ultrafast intramolecular relaxation is strongly coupled to a specific vibrational mode, resulting in the concerted transfer of population and coherence between excited states on a sub-100 fs timescale. DNA-templated silver nanoclusters possess desirable optical properties, but their excited state dynamics remain poorly understood. Here the authors show that intracluster relaxations in such clusters are strongly coupled to a vibrational mode, resulting in ultrafast concerted transfer of population and coherence between excited states.
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Shah P, Cho SK, Thulstrup PW, Bjerrum MJ, Lee PH, Kang JH, Bhang YJ, Yang SW. MicroRNA Biomarkers in Neurodegenerative Diseases and Emerging Nano-Sensors Technology. J Mov Disord 2017; 10:18-28. [PMID: 28122423 PMCID: PMC5288660 DOI: 10.14802/jmd.16037] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2016] [Revised: 11/12/2016] [Accepted: 11/22/2016] [Indexed: 12/18/2022] Open
Abstract
MicroRNAs (miRNAs) are essential small RNA molecules (20–24 nt) that negatively regulate the expression of target genes at the post-transcriptional level. Due to their roles in a variety of biological processes, the aberrant expression profiles of miRNAs have been identified as biomarkers for many diseases, such as cancer, diabetes, cardiovascular disease and neurodegenerative diseases. In order to precisely, rapidly and economically monitor the expression of miRNAs, many cutting-edge nanotechnologies have been developed. One of the nanotechnologies, based on DNA encapsulated silver nanoclusters (DNA/AgNCs), has increasingly been adopted to create nanoscale bio-sensing systems due to its attractive optical properties, such as brightness, tuneable emission wavelengths and photostability. Using the DNA/AgNCs sensor methods, the presence of miRNAs can be detected simply by monitoring the fluorescence alteration of DNA/AgNCs sensors. We introduce these DNA/ AgNCs sensor methods and discuss their possible applications for detecting miRNA biomarkers in neurodegenerative diseases.
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Affiliation(s)
- Pratik Shah
- UNIK Center for Synthetic Biology, University of Copenhagen, Copenhagen, Denmark.,Department of Biomedical Engineering, University of California Irvine, Irvine, CA, USA
| | - Seok Keun Cho
- Department of Systems Biology, College of Life Science and Biotechnology, Yonsei University, Seoul, Korea
| | | | | | - Phil Hyu Lee
- Department of Neurology, Severance Biomedical Science Institute, Yonsei University College of Medicine, Seoul, Korea
| | - Ju-Hee Kang
- Department of Pharmacology, Hypoxia-related Disease Research Center, Inha University School of Medicine, Incheon, Korea
| | | | - Seong Wook Yang
- UNIK Center for Synthetic Biology, University of Copenhagen, Copenhagen, Denmark.,Department of Systems Biology, College of Life Science and Biotechnology, Yonsei University, Seoul, Korea
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New SY, Lee ST, Su XD. DNA-templated silver nanoclusters: structural correlation and fluorescence modulation. NANOSCALE 2016; 8:17729-17746. [PMID: 27722695 DOI: 10.1039/c6nr05872h] [Citation(s) in RCA: 102] [Impact Index Per Article: 12.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/21/2023]
Abstract
12 years after the introduction of DNA-templated silver nanoclusters (DNA-AgNCs), exciting progress has been made and yet we are still in the midst of trying to fully understand this nanomaterial. The prominent excellence of DNA-AgNCs is undoubtedly its modulatable emission property, of which how variation in DNA templates causes emission tuning remains elusive. Based on the up-to-date DNA-AgNCs, we aim to establish the correlation between the structure/sequence of DNA templates and emission behaviour of AgNCs. Herein, we systematically present a wide-range of DNA-AgNCs based on the structural complexity of the DNA templates, including single-stranded DNA (ssDNA), double-stranded DNA (dsDNA), triple-stranded DNA (tsDNA) and DNA nanostructures. For each DNA category, we discuss the emission property, quantum yield and synthesis condition of the respective AgNCs, before cross-comparing the impact of different DNA scaffolds on the properties of AgNCs. A future outlook for this area is given as a conclusion. By putting the information together, this review may shed new light on understanding DNA-AgNCs while we are expecting continuous breakthroughs in this field.
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Affiliation(s)
- S Y New
- School of Pharmacy, Faculty of Science, University of Nottingham Malaysia Campus, Jalan Broga, 43500 Semenyih, Selangor Darul Ehsan, Malaysia.
| | - S T Lee
- School of Pharmacy, Faculty of Science, University of Nottingham Malaysia Campus, Jalan Broga, 43500 Semenyih, Selangor Darul Ehsan, Malaysia.
| | - X D Su
- Institute of Materials Research and Engineering, 2 Fusionopolis Way, Singapore 138634.
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Yu Y, Mok BYL, Loh XJ, Tan YN. Rational Design of Biomolecular Templates for Synthesizing Multifunctional Noble Metal Nanoclusters toward Personalized Theranostic Applications. Adv Healthc Mater 2016; 5:1844-59. [PMID: 27377035 DOI: 10.1002/adhm.201600192] [Citation(s) in RCA: 58] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2016] [Revised: 04/08/2016] [Indexed: 12/21/2022]
Abstract
Biomolecule-templated or biotemplated metal nanoclusters (NCs) are ultrasmall (<2 nm) metal (Au, Ag) particles stabilized by a certain type of biomolecular template (e.g., peptides, proteins, and DNA). Due to their unique physiochemical properties, biotemplated metal NCs have been widely used in sensing, imaging, delivery and therapy. The overwhelming applications in these individual areas imply the great promise of harnessing biotemplated metal NCs in more advanced biomedical aspects such as theranostics. Although applications of biotemplated metal NCs as theranostic agents are trending, the rational design of biomolecular templates suitable for the synthesis of multifunctional metal NCs for theranostics is comparatively underexplored. This progress report first identifies the essential attributes of biotemplated metal NCs for theranostics by reviewing the state-of-art applications in each of the four modalities of theranostics, namely sensing, imaging, delivery and therapy. To achieve high efficacy in these modalities, we elucidate the design principles underlying the use of biomolecules (proteins, peptides and nucleic acids) to control the NC size, emission color and surface chemistries for post-functionalization of therapeutic moieties. We then propose a unified strategy to engineer biomolecular templates that combine all these modalities to produce multifunctional biotemplated metal NCs that can serve as the next-generation personalized theranostic agents.
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Affiliation(s)
- Yong Yu
- Institute of Materials Research and Engineering; The Agency for Science, Technology and Research (A*STAR); 2 Fusionopolis Way, #08-03 Innovis 138634 Singapore
| | - Beverly Y. L. Mok
- Institute of Materials Research and Engineering; The Agency for Science, Technology and Research (A*STAR); 2 Fusionopolis Way, #08-03 Innovis 138634 Singapore
| | - Xian Jun Loh
- Institute of Materials Research and Engineering; The Agency for Science, Technology and Research (A*STAR); 2 Fusionopolis Way, #08-03 Innovis 138634 Singapore
| | - Yen Nee Tan
- Institute of Materials Research and Engineering; The Agency for Science, Technology and Research (A*STAR); 2 Fusionopolis Way, #08-03 Innovis 138634 Singapore
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Petty JT, Sergev OO, Ganguly M, Rankine IJ, Chevrier DM, Zhang P. A Segregated, Partially Oxidized, and Compact Ag10 Cluster within an Encapsulating DNA Host. J Am Chem Soc 2016; 138:3469-77. [PMID: 26924556 PMCID: PMC6118400 DOI: 10.1021/jacs.5b13124] [Citation(s) in RCA: 51] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Silver clusters develop within DNA strands and become optical chromophores with diverse electronic spectra and wide-ranging emission intensities. These studies consider a specific cluster that absorbs at 400 nm, has low emission, and exclusively develops with single-stranded oligonucleotides. It is also a chameleon-like chromophore that can be transformed into different highly emissive fluorophores. We describe four characteristics of this species and conclude that it is highly oxidized yet also metallic. One, the cluster size was determined via electrospray ionization mass spectrometry. A common silver mass is measured with different oligonucleotides and thereby supports a Ag10 cluster. Two, the cluster charge was determined by mass spectrometry and Ag L3-edge X-ray absorption near-edge structure spectroscopy. Respectively, the conjugate mass and the integrated white-line intensity support a partially oxidized cluster with a +6 and +6.5 charge, respectively. Three, the cluster chirality was gauged by circular dichroism spectroscopy. This chirality changes with the length and sequence of its DNA hosts, and these studies identified a dispersed binding site with ∼20 nucleobases. Four, the structure of this complex was investigated via Ag K-edge extended X-ray absorption fine structure spectroscopy. A multishell fitting analysis identified three unique scattering environments with corresponding bond lengths, coordination numbers, and Debye-Waller factors for each. Collectively, these findings support the following conclusion: a Ag10(+6) cluster develops within a 20-nucleobase DNA binding site, and this complex segregates into a compact, metal-like silver core that weakly links to an encapsulating silver-DNA shell. We consider different models that account for silver-silver coordination within the core.
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Affiliation(s)
- Jeffrey T. Petty
- Department of Chemistry, Furman University, Greenville, South Carolina 29613, United States
| | - Orlin O. Sergev
- Department of Chemistry, Furman University, Greenville, South Carolina 29613, United States
| | - Mainak Ganguly
- Department of Chemistry, Furman University, Greenville, South Carolina 29613, United States
| | - Ian J. Rankine
- Department of Chemistry, Furman University, Greenville, South Carolina 29613, United States
| | - Daniel M. Chevrier
- Department of Chemistry, Dalhousie University, Halifax, Nova Scotia B3H 4R2, Canada
| | - Peng Zhang
- Department of Chemistry, Dalhousie University, Halifax, Nova Scotia B3H 4R2, Canada
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Shah P, Choi SW, Kim HJ, Cho SK, Bhang YJ, Ryu MY, Thulstrup PW, Bjerrum MJ, Yang SW. Locking-to-unlocking system is an efficient strategy to design DNA/silver nanoclusters (AgNCs) probe for human miRNAs. Nucleic Acids Res 2015; 44:e57. [PMID: 26681688 PMCID: PMC4824086 DOI: 10.1093/nar/gkv1377] [Citation(s) in RCA: 39] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2015] [Accepted: 11/19/2015] [Indexed: 12/18/2022] Open
Abstract
MicroRNAs (miRNAs), small non-coding RNA molecules, are important biomarkers for research and medical purposes. Here, we describe the development of a fast and simple method using highly fluorescent oligonucleotide-silver nanocluster probes (DNA/AgNCs) to efficiently detect specific miRNAs. Due to the great sequence diversity of miRNAs in humans and other organisms, a uniform strategy for miRNA detection is attractive. The concept presented is an oligonucleotide-based locking-to-unlocking system that can be endowed with miRNA complementarity while maintaining the same secondary structure. The locking-to-unlocking system is based on fold-back anchored DNA templates that consist of a cytosine-rich loop for AgNCs stabilization, an miRNA recognition site and an overlap region for hairpin stabilization. When an miRNA is recognized, fluorescence in the visible region is specifically extinguished in a concentration-dependent manner. Here, the exact composition of the fold-back anchor for the locking-to-unlocking system has been systematically optimized, balancing propensity for loop-structure formation, encapsulation of emissive AgNCs and target sensitivity. It is demonstrated that the applied strategy successfully can detect a number of cancer related miRNAs in RNA extracts from human cancer cell lines.
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Affiliation(s)
- Pratik Shah
- UNIK Center for Synthetic Biology, University of Copenhagen, Thorvaldsensvej 40, DK-1871 Frederiksberg C, Copenhagen, Denmark
| | - Suk Won Choi
- Department of Chemistry, University of Copenhagen, Universitetsparken 5, DK-2100, Copenhagen, Denmark
| | - Ho-Jin Kim
- Department of Chemistry, University of Copenhagen, Universitetsparken 5, DK-2100, Copenhagen, Denmark
| | - Seok Keun Cho
- UNIK Center for Synthetic Biology, University of Copenhagen, Thorvaldsensvej 40, DK-1871 Frederiksberg C, Copenhagen, Denmark
| | - Yong-Joo Bhang
- Department of Chemistry, University of Copenhagen, Universitetsparken 5, DK-2100, Copenhagen, Denmark
| | - Moon Young Ryu
- UNIK Center for Synthetic Biology, University of Copenhagen, Thorvaldsensvej 40, DK-1871 Frederiksberg C, Copenhagen, Denmark
| | - Peter Waaben Thulstrup
- Seoulin Bioscience Co. Ltd. 4F. #A, KOREA BIO PARK, 700, Daewangpangyo-ro, Bundang-gu, Seongnam-si, Gyeonggi-do, Korea
| | - Morten Jannik Bjerrum
- Seoulin Bioscience Co. Ltd. 4F. #A, KOREA BIO PARK, 700, Daewangpangyo-ro, Bundang-gu, Seongnam-si, Gyeonggi-do, Korea
| | - Seong Wook Yang
- UNIK Center for Synthetic Biology, University of Copenhagen, Thorvaldsensvej 40, DK-1871 Frederiksberg C, Copenhagen, Denmark Department of Systems Biology, College of Life Science and Biotechnology, Yonsei University, Korea
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Ganguly M, Bradsher C, Goodwin P, Petty JT. DNA-Directed Fluorescence Switching of Silver Clusters. THE JOURNAL OF PHYSICAL CHEMISTRY. C, NANOMATERIALS AND INTERFACES 2015; 119:27829-27837. [PMID: 30220954 PMCID: PMC6136663 DOI: 10.1021/acs.jpcc.5b08834] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/10/2023]
Abstract
Silver clusters with ≲30 atoms are molecules with diverse electronic spectra and wide-ranging emission intensities. Specific cluster chromophores form within DNA strands, and we consider a DNA scaffold that transforms a pair of silver clusters. This ~20-nucleotide strand has two components, a cluster domain (S1) that stabilizes silver clusters and a recognition site (S2) that hybridizes with complementary oligonucleotides (S2C). The single-stranded S1-S2 exclusively develops clusters with violet absorption and low emission. This conjugate hybridizes with S2C to form S1-S2:S2C, and the violet chromophore transforms to a fluorescent counterpart with λex ≈ 490 nm/λem ≈ 550 nm and with ~100-fold stronger emission. Our studies focus on both the S1 sequence and structure that direct this violet → blue-green cluster transformation. From the sequence perspective, C4X sequences with X = adenine, thymine, and/or guanine favor the blue-green cluster, and the specificity of the binding site depends on three factors: the number of C4X repeats, the identity of the X nucleobase, and the number of contiguous cytosines. A systematic series of oligonucleotides identified the optimal S1 sequence C4AC4T and discerned distinct roles for the adenine, thymine, and cytosines. From the structure perspective, two factors guide the conformation of the C4AC4T sequence: hybridization with the S2C complement and coordination by the cluster adduct. Spectroscopic and chromatographic studies show that the single-stranded C4AC4T is folded by its blue-green cluster adduct. We propose a structural model in which the two C4X motifs within C4AC4T are cross-linked by the encapsulated cluster. These studies suggest that the structures of the DNA host and the cluster adduct are interdependent.
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Affiliation(s)
- Mainak Ganguly
- Department of Chemistry, Furman University, Greenville, South Carolina 29613, United States
| | - Cara Bradsher
- Department of Chemistry, Furman University, Greenville, South Carolina 29613, United States
| | - Peter Goodwin
- Center for Integrated Nanotechnologies, Los Alamos National Laboratory, Los Alamos, New Mexico 87545, United States
| | - Jeffrey T. Petty
- Department of Chemistry, Furman University, Greenville, South Carolina 29613, United States
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Petty JT, Sergev OO, Kantor AG, Rankine IJ, Ganguly M, David FD, Wheeler SK, Wheeler JF. Ten-atom silver cluster signaling and tempering DNA hybridization. Anal Chem 2015; 87:5302-9. [PMID: 25923963 DOI: 10.1021/acs.analchem.5b01265] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
Silver clusters with ∼10 atoms are molecules, and specific species develop within DNA strands. These molecular metals have sparsely organized electronic states with distinctive visible and near-infrared spectra that vary with cluster size, oxidation, and shape. These small molecules also act as DNA adducts and coordinate with their DNA hosts. We investigated these characteristics using a specific cluster-DNA conjugate with the goal of developing a sensitive and selective biosensor. The silver cluster has a single violet absorption band (λ(max) = 400 nm), and its single-stranded DNA host has two domains that stabilize this cluster and hybridize with target oligonucleotides. These target analytes transform the weakly emissive violet cluster to a new chromophore with blue-green absorption (λ(max) = 490 nm) and strong green emission (λ(max) = 550 nm). Our studies consider the synthesis, cluster size, and DNA structure of the precursor violet cluster-DNA complex. This species preferentially forms with relatively low amounts of Ag(+), high concentrations of the oxidizing agent O2, and DNA strands with ≳20 nucleotides. The resulting aqueous and gaseous forms of this chromophore have 10 silvers that coalesce into a single cluster. This molecule is not only a chromophore but also an adduct that coordinates multiple nucleobases. Large-scale DNA conformational changes are manifested in a 20% smaller hydrodynamic radius and disrupted nucleobase stacking. Multidentate coordination also stabilizes the single-stranded DNA and thereby inhibits hybridization with target complements. These observations suggest that the silver cluster-DNA conjugate acts like a molecular beacon but is distinguished because the cluster chromophore not only sensitively signals target analytes but also stringently discriminates against analogous competing analytes.
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Affiliation(s)
- Jeffrey T Petty
- Department of Chemistry, Furman University, Greenville, South Carolina 29613, United States
| | - Orlin O Sergev
- Department of Chemistry, Furman University, Greenville, South Carolina 29613, United States
| | - Andrew G Kantor
- Department of Chemistry, Furman University, Greenville, South Carolina 29613, United States
| | - Ian J Rankine
- Department of Chemistry, Furman University, Greenville, South Carolina 29613, United States
| | - Mainak Ganguly
- Department of Chemistry, Furman University, Greenville, South Carolina 29613, United States
| | - Frederic D David
- Department of Chemistry, Furman University, Greenville, South Carolina 29613, United States
| | - Sandra K Wheeler
- Department of Chemistry, Furman University, Greenville, South Carolina 29613, United States
| | - John F Wheeler
- Department of Chemistry, Furman University, Greenville, South Carolina 29613, United States
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Shah P, Choi SW, Kim HJ, Cho SK, Thulstrup PW, Bjerrum MJ, Bhang YJ, Ahn JC, Yang SW. DNA/RNA chimera templates improve the emission intensity and target the accessibility of silver nanocluster-based sensors for human microRNA detection. Analyst 2015; 140:3422-30. [PMID: 25759134 DOI: 10.1039/c5an00093a] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
In recent years microRNAs (miRNAs) have been established as important biomarkers in a variety of diseases including cancer, diabetes, cardiovascular disease, aging, Alzheimer's disease, asthma, autoimmune disease and liver diseases. As a consequence, a variety of monitoring methods for miRNAs have been developed, including a fast and simple method for miRNA detection by exploitation of the unique photoluminescence of DNA-templated silver nanoclusters (DNA/AgNCs). To increase the versatility of the AgNC-based method, we have adopted DNA/RNA chimera templates for AgNC-based probes, allowing response from several human miRNAs which are hardly detectable with DNA-based probes. Here, we demonstrate in detail the power of DNA/RNA chimera/AgNC probes in detecting two human miRNAs, let-7a and miR-200c. The DNA/RNA chimera-based probes are highly efficient to determine the level of miRNAs in several human cell lines.
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Affiliation(s)
- Pratik Shah
- UNIK Center for Synthetic Biology, University of Copenhagen, Thorvaldsensvej 40, DK-1871 Frederiksberg C, Copenhagen, Denmark.
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Gwinn E, Schultz D, Copp SM, Swasey S. DNA-Protected Silver Clusters for Nanophotonics. NANOMATERIALS 2015; 5:180-207. [PMID: 28347005 PMCID: PMC5312861 DOI: 10.3390/nano5010180] [Citation(s) in RCA: 79] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/16/2014] [Accepted: 02/05/2015] [Indexed: 01/08/2023]
Abstract
DNA-protected silver clusters (AgN-DNA) possess unique fluorescence properties that depend on the specific DNA template that stabilizes the cluster. They exhibit peak emission wavelengths that range across the visible and near-IR spectrum. This wide color palette, combined with low toxicity, high fluorescence quantum yields of some clusters, low synthesis costs, small cluster sizes and compatibility with DNA are enabling many applications that employ AgN-DNA. Here we review what is known about the underlying composition and structure of AgN-DNA, and how these relate to the optical properties of these fascinating, hybrid biomolecule-metal cluster nanomaterials. We place AgN-DNA in the general context of ligand-stabilized metal clusters and compare their properties to those of other noble metal clusters stabilized by small molecule ligands. The methods used to isolate pure AgN-DNA for analysis of composition and for studies of solution and single-emitter optical properties are discussed. We give a brief overview of structurally sensitive chiroptical studies, both theoretical and experimental, and review experiments on bringing silver clusters of distinct size and color into nanoscale DNA assemblies. Progress towards using DNA scaffolds to assemble multi-cluster arrays is also reviewed.
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Affiliation(s)
- Elisabeth Gwinn
- Department of Physics, The University of California, Santa Barbara, Santa Barbara, CA 93106, USA.
| | - Danielle Schultz
- Department of Chemistry and Biochemistry, The University of California, Santa Barbara, Santa Barbara, CA 93106, USA.
| | - Stacy M Copp
- Department of Physics, The University of California, Santa Barbara, Santa Barbara, CA 93106, USA.
| | - Steven Swasey
- Department of Chemistry and Biochemistry, The University of California, Santa Barbara, Santa Barbara, CA 93106, USA.
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Ganguly M, Jana J, Das B, Dhara S, Pal A, Pal T. Orange-red silver emitters for sensing application and bio-imaging. Dalton Trans 2015; 44:11457-69. [DOI: 10.1039/c5dt00928f] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
Strongly fluorescent HFL-containing Ag@Au particles are synthesized via a modified hydrothermal technique. This solution is used for sulfide sensing and cell imaging.
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Affiliation(s)
| | - Jayasmita Jana
- Department of Chemistry
- Indian Institute of Technology
- Kharagpur-721302
- India
| | - Bodhisatwa Das
- School of Medical Science & Technology
- Indian Institute of Technology
- Kharagpur-721302
- India
| | - Santanu Dhara
- School of Medical Science & Technology
- 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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36
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Staelens N, Leherte L, Champagne B, Vercauteren DP. Modeling of structural, energetic, and dynamic properties of few-atom silver clusters embedded in polynucleotide strands by using molecular dynamics. Chemphyschem 2014; 16:360-9. [PMID: 25412871 DOI: 10.1002/cphc.201402632] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2014] [Indexed: 12/23/2022]
Abstract
This work concerns the study of the structural, energetic, and dynamic properties of fluorescent systems composed of silver clusters stabilized by polynucleotide strands. To do so, classical interaction potentials relative to silver, neutral and cationic, were introduced in the AMBER force field. Molecular dynamics simulations allowed analysis of the nature and force of the interactions between the various parts of the nucleic oligomers and the silver clusters. Conformational analyses were necessary to explore the flexibility of the supramolecular assemblies, specifically by radial distribution functions and Ramachandran-type maps.
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Affiliation(s)
- Nicolas Staelens
- Laboratoire de Physico-Chimie Informatique (PCI), Unité de Chimie Physique Théorique et Structurale (UCPTS), Université de Namur, Rue de Bruxelles 61, 5000 Namur (Belgium).
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37
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Obliosca JM, Babin MC, Liu C, Liu YL, Chen YA, Batson RA, Ganguly M, Petty JT, Yeh HC. A complementary palette of NanoCluster Beacons. ACS NANO 2014; 8:10150-60. [PMID: 25299363 PMCID: PMC4212725 DOI: 10.1021/nn505338e] [Citation(s) in RCA: 61] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/11/2023]
Abstract
NanoCluster Beacons (NCBs), which use few-atom DNA-templated silver clusters as reporters, are a type of activatable molecular probes that are low-cost and easy to prepare. While NCBs provide a high fluorescence enhancement ratio upon activation, their activation colors are currently limited. Here we report a simple method to design NCBs with complementary emission colors, creating a set of multicolor probes for homogeneous, separation-free detection. By systematically altering the position and the number of cytosines in the cluster-nucleation sequence, we have tuned the activation colors of NCBs to green (C8-8, 460 nm/555 nm); yellow (C5-5, 525 nm/585 nm); red (C3-4, 580 nm/635 nm); and near-infrared (C3-3, 645 nm/695 nm). At the same NCB concentration, the activated yellow NCB (C5-5) was found to be 1.3 times brighter than the traditional red NCB (C3-4). Three of the four colors (green, yellow, and red) were relatively spectrally pure. We also found that subtle changes in the linker sequence (down to the single-nucleotide level) could significantly alter the emission spectrum pattern of an NCB. When the length of linker sequences was increased, the emission peaks were found to migrate in a periodic fashion, suggesting short-range interactions between silver clusters and nucleobases. Size exclusion chromatography results indicated that the activated NCBs are more compact than their native duplex forms. Our findings demonstrate the unique photophysical properties and environmental sensitivities of few-atom DNA-templated silver clusters, which are not seen before in common organic dyes or luminescent crystals.
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Affiliation(s)
- Judy M. Obliosca
- Department of Biomedical Engineering, University of Texas at Austin, Austin, Texas 78712, United States
| | - Mark C. Babin
- Department of Chemistry, University of Texas at Austin, Austin, Texas 78712, United States
| | - Cong Liu
- Department of Biomedical Engineering, University of Texas at Austin, Austin, Texas 78712, United States
| | - Yen-Liang Liu
- Department of Biomedical Engineering, University of Texas at Austin, Austin, Texas 78712, United States
| | - Yu-An Chen
- Department of Biomedical Engineering, University of Texas at Austin, Austin, Texas 78712, United States
| | - Robert A. Batson
- Department of Biomedical Engineering, University of Texas at Austin, Austin, Texas 78712, United States
| | - Mainak Ganguly
- Department of Chemistry, Furman University, Greenville, South Carolina 29613, United States
| | - Jeffrey T. Petty
- Department of Chemistry, Furman University, Greenville, South Carolina 29613, United States
- Address correspondence to ,
| | - Hsin-Chih Yeh
- Department of Biomedical Engineering, University of Texas at Austin, Austin, Texas 78712, United States
- Address correspondence to ,
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Petty JT, Nicholson D, Sergev OO, Graham SK. Near-infrared silver cluster optically signaling oligonucleotide hybridization and assembling two DNA hosts. Anal Chem 2014; 86:9220-8. [PMID: 25157472 PMCID: PMC4165452 DOI: 10.1021/ac502192w] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2014] [Accepted: 08/26/2014] [Indexed: 12/11/2022]
Abstract
Silver clusters with ~10 atoms form within DNA strands, and the conjugates are chemical sensors. The DNA host hybridizes with short oligonucleotides, and the cluster moieties optically respond to these analytes. Our studies focus on how the cluster adducts perturb the structure of their DNA hosts. Our sensor is comprised of an oligonucleotide with two components: a 5'-cluster domain that complexes silver clusters and a 3'-recognition site that hybridizes with a target oligonucleotide. The single-stranded sensor encapsulates an ~11 silver atom cluster with violet absorption at 400 nm and with minimal emission. The recognition site hybridizes with complementary oligonucleotides, and the violet cluster converts to an emissive near-infrared cluster with absorption at 730 nm. Our key finding is that the near-infrared cluster coordinates two of its hybridized hosts. The resulting tertiary structure was investigated using intermolecular and intramolecular variants of the same dimer. The intermolecular dimer assembles in concentrated (~5 μM) DNA solutions. Strand stoichiometries and orientations were chromatographically determined using thymine-modified complements that increase the overall conjugate size. The intramolecular dimer develops within a DNA scaffold that is founded on three linked duplexes. The high local cluster concentrations and relative strand arrangements again favor the antiparallel dimer for the near-infrared cluster. When the two monomeric DNA/violet cluster conjugates transform to one dimeric DNA/near-infrared conjugate, the DNA strands accumulate silver. We propose that these correlated changes in DNA structure and silver stoichiometry underlie the violet to near-infrared cluster transformation.
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Affiliation(s)
| | - David
A. Nicholson
- Department of Chemistry, Furman
University, Greenville, South Carolina 29613, United States
| | - Orlin O. Sergev
- Department of Chemistry, Furman
University, Greenville, South Carolina 29613, United States
| | - Stuart K. Graham
- Department of Chemistry, Furman
University, Greenville, South Carolina 29613, United States
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Shah P, Cho SK, Thulstrup PW, Bhang YJ, Ahn JC, Choi SW, Rørvig-Lund A, Yang SW. Effect of salts, solvents and buffer on miRNA detection using DNA silver nanocluster (DNA/AgNCs) probes. NANOTECHNOLOGY 2014; 25:045101. [PMID: 24393838 DOI: 10.1088/0957-4484/25/4/045101] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
MicroRNAs (miRNAs) are small regulatory RNAs (size ~21 nt to ~25 nt) which regulate a variety of important cellular events in plants, animals and single cell eukaryotes. Especially because of their use in diagnostics of human diseases, efforts have been directed towards the invention of a rapid, simple and sequence selective detection method for miRNAs. Recently, we reported an innovative method for the determination of miRNA levels using the red fluorescent properties of DNA/silver nanoclusters (DNA/AgNCs). Our method is based on monitoring the emission drop of a DNA/AgNCs probe in the presence of its specific target miRNA. Accordingly, the accuracy and efficiency of the method relies on the sensitivity of hybridization between the probe and target. To gain specific and robust hybridization between probe and target, we investigated a range of diverse salts, organic solvents, and buffer to optimize target sensing conditions. Under the newly adjusted conditions, the target sensitivity and the formation of emissive DNA/AgNCs probes were significantly improved. Also, fortification of the Tris-acetate buffer with inorganic salts or organic solvents improved the sensitivity of the DNA/AgNC probes. On the basis of these optimizations, the versatility of the DNA/AgNCs-based miRNA detection method can be expanded.
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Affiliation(s)
- Pratik Shah
- UNIK Center for Synthetic Biology/Plant Biochemistry Laboratory, Department of Plant and Environmental Sciences, University of Copenhagen, Thorvaldsensvej 4, DK-1871 Frederiksberg C, Copenhagen, Denmark
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40
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Xia X, Hao Y, Hu S, Wang J. Hairpin DNA probe with 5′-TCC/CCC-3′ overhangs for the creation of silver nanoclusters and miRNA assay. Biosens Bioelectron 2014; 51:36-9. [DOI: 10.1016/j.bios.2013.07.036] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2013] [Revised: 07/13/2013] [Accepted: 07/19/2013] [Indexed: 02/05/2023]
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Shah P, Thulstrup PW, Cho SK, Bjerrum MJ, Yang SW. DNA–RNA chimera indicates the flexibility of the backbone influences the encapsulation of fluorescent AgNC emitters. Chem Commun (Camb) 2014; 50:13592-5. [DOI: 10.1039/c4cc06439a] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
Many DNA scaffolds efficiently encapsulate highly emissive silver nanoclusters (AgNCs).
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Affiliation(s)
- Pratik Shah
- UNIK Center for Synthetic Biology
- University of Copenhagen
- Copenhagen, Denmark
| | | | - Seok Keun Cho
- UNIK Center for Synthetic Biology
- University of Copenhagen
- Copenhagen, Denmark
| | | | - Seong Wook Yang
- UNIK Center for Synthetic Biology
- University of Copenhagen
- Copenhagen, Denmark
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42
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Petty JT, Sergev OO, Nicholson DA, Goodwin PM, Giri B, McMullan DR. A silver cluster-DNA equilibrium. Anal Chem 2013; 85:9868-76. [PMID: 24032398 PMCID: PMC4532306 DOI: 10.1021/ac4028559] [Citation(s) in RCA: 46] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
DNA encapsulates silver clusters, and these hybrid nanomaterials form molecular sensors. We discuss a silver cluster-oligonucleotide sensor with four characteristics. First, a specific reporting cluster forms within a single-stranded DNA. This template uses the 5' cluster domain CCCCAACTCCTT with different 3' recognition sites for complementary oligonucleotides. The modular composite strand exclusively forms a cluster with λmax = 400 nm and with low emission. Conjugates were chromatographically purified, and their elemental analysis measured a cluster adduct with ∼11 silver atoms. Second, hybridization transforms the cluster. Size exclusion chromatography shows that the 3' recognition sites of the single-stranded conjugates hybridize with their complements. This secondary structural change both shifts cluster absorption from 400 to 490 nm and develops emission at 550 nm. Third, cluster size remains intact. Like their violet predecessors, purified blue-green clusters have ∼11 silver atoms. Cluster integrity is further supported by extracting the complement from the blue-green conjugate and reversing the spectral changes. Fourth, the cluster transformation is an equilibrium. Complementary strands generate an isosbestic point and thus directly link single-stranded hosts for the violet cluster and their hybridized analogs for the blue-green cluster. This equilibrium shifts with temperature. A van't Hoff analysis shows that longer and more stable duplexes favor the blue-green cluster. However, hybridized cluster hosts are less stable than their native DNA counterparts, and stability further degrades when short complements expose nucleobases within S1-S2. Duplex instability suggests that unpaired nucleobases coordinate the violet cluster and favor the single-stranded sensor. A balance between innate hybridization and exogenous folding highlights a distinct feature of silver clusters for sensing: they are both chromophoric reporters and ligands that modulate analyte-sensor interactions.
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Affiliation(s)
- Jeffrey T. Petty
- Department of Chemistry, Furman University, Greenville, SC 29613
| | - Orlin O. Sergev
- Department of Chemistry, Furman University, Greenville, SC 29613
| | | | | | - Banabihari Giri
- Department of Chemistry, Furman University, Greenville, SC 29613
| | - D. Ryan McMullan
- Department of Chemistry, Furman University, Greenville, SC 29613
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43
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Abstract
Fluorescent silver nanoclusters (few atoms, quantum sized) have attracted much attention as promising substitutes for conventional fluorophores. Due to their unique environmental sensitivities, new fluorescent probes have been developed based on silver nanoclusters for the sensitive and specific detection of DNA. In this review we present the recent discoveries of activatable and color-switchable properties of DNA-templated silver nanoclusters and discuss the strategies to use these new properties in DNA sensing.
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Affiliation(s)
- Judy M Obliosca
- Department of Biomedical Engineering, University of Texas at Austin, Austin, TX 78712, USA
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Obliosca JM, Liu C, Batson RA, Babin MC, Werner JH, Yeh HC. DNA/RNA Detection Using DNA-Templated Few-Atom Silver Nanoclusters. BIOSENSORS-BASEL 2013; 3:185-200. [PMID: 25586126 PMCID: PMC4263537 DOI: 10.3390/bios3020185] [Citation(s) in RCA: 54] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/11/2013] [Revised: 04/10/2013] [Accepted: 04/11/2013] [Indexed: 12/17/2022]
Abstract
DNA-templated few-atom silver nanoclusters (DNA/Ag NCs) are a new class of organic/inorganic composite nanomaterials whose fluorescence emission can be tuned throughout the visible and near-IR range by simply programming the template sequences. Compared to organic dyes, DNA/Ag NCs can be brighter and more photostable. Compared to quantum dots, DNA/Ag NCs are smaller, less prone to blinking on long timescales, and do not have a toxic core. The preparation of DNA/Ag NCs is simple and there is no need to remove excess precursors as these precursors are non-fluorescent. Our recent discovery of the fluorogenic and color switching properties of DNA/Ag NCs have led to the invention of new molecular probes, termed NanoCluster Beacons (NCBs), for DNA detection, with the capability to differentiate single-nucleotide polymorphisms by emission colors. NCBs are inexpensive, easy to prepare, and compatible with commercial DNA synthesizers. Many other groups have also explored and taken advantage of the environment sensitivities of DNA/Ag NCs in creating new tools for DNA/RNA detection and single-nucleotide polymorphism identification. In this review, we summarize the recent trends in the use of DNA/Ag NCs for developing DNA/RNA sensors.
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Affiliation(s)
- Judy M Obliosca
- Department of Biomedical Engineering, Cockrell School of Engineering, University of Texas at Austin, Austin, TX 78712, USA.
| | - Cong Liu
- Department of Biomedical Engineering, Cockrell School of Engineering, University of Texas at Austin, Austin, TX 78712, USA.
| | - Robert Austin Batson
- Department of Biomedical Engineering, Cockrell School of Engineering, University of Texas at Austin, Austin, TX 78712, USA.
| | - Mark C Babin
- College of Natural Sciences, University of Texas at Austin, Austin, TX 78712, USA.
| | - James H Werner
- Center for Integrated Nanotechnologies, Los Alamos National Laboratory, Los Alamos, NM 78745, USA.
| | - Hsin-Chih Yeh
- Department of Biomedical Engineering, Cockrell School of Engineering, University of Texas at Austin, Austin, TX 78712, USA.
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