1
|
Mahmood AU, Rizvi MH, Tracy JB, Yingling YG. Solvent Effects in Ligand Stripping Behavior of Colloidal Nanoparticles. ACS NANO 2023. [PMID: 37311219 DOI: 10.1021/acsnano.3c01313] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/15/2023]
Abstract
Inorganic colloidal nanoparticle (NP) properties can be tuned by stripping stabilizing ligands using a poor solvent. However, the mechanism behind ligand stripping is poorly understood, in part because in situ measurements of ligand stripping are challenging at the nanoscale. Here, we investigate ethanol solvent-mediated oleylamine ligand stripping from magnetite (Fe3O4) NPs in different compositions of ethanol/hexane mixtures using atomistic molecular dynamics (MD) simulations and thermogravimetric analysis (TGA). Our study elucidates a complex interplay of ethanol interactions with system components and indicates the existence of a threshold concentration of ∼34 vol % ethanol, above which ligand stripping saturates. Moreover, hydrogen bonding between ethanol and stripped ligands inhibits subsequent readsorption of the ligands on the NP surface. A proposed modification of the Langmuir isotherm explains the role of the enthalpy of mixing of the ligands and solvents on the ligand stripping mechanism. A good agreement between the MD predictions and TGA measurements of ligand stripping from Fe3O4 NPs validates the simulation observations. Our findings demonstrate that the ligand coverage of NPs can be controlled by using a poor solvent below the threshold concentration and highlight the importance of ligand-solvent interactions that modulate the properties of colloidal NPs. The study also provides an approach for a detailed in silico study of ligand stripping and exchange from colloidal NPs that are crucial for applications of NPs spanning self-assembly, optoelectronics, nanomedicine, and catalysis.
Collapse
Affiliation(s)
- Akhlak U Mahmood
- Department of Materials Science and Engineering, North Carolina State University, Raleigh, North Carolina 27695, United States
| | - Mehedi H Rizvi
- Department of Materials Science and Engineering, North Carolina State University, Raleigh, North Carolina 27695, United States
| | - Joseph B Tracy
- Department of Materials Science and Engineering, North Carolina State University, Raleigh, North Carolina 27695, United States
| | - Yaroslava G Yingling
- Department of Materials Science and Engineering, North Carolina State University, Raleigh, North Carolina 27695, United States
| |
Collapse
|
2
|
Singapati AY, Muthuraja V, Kuthe AM, Ravikumar C. Influence of the Molecular Weight of Poly (Ethylene Glycol) on the Aqueous Dispersion State of Magnetic Nanoparticles: Experiments and Monte Carlo Simulation. J CLUST SCI 2022. [DOI: 10.1007/s10876-022-02360-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
|
3
|
Pasek-Allen JL, Wilharm RK, Gao Z, Pierre VC, Bischof JC. Phosphonate coating of commercial iron oxide nanoparticles for nanowarming cryopreserved samples. J Mater Chem B 2022; 10:3734-3746. [PMID: 35466332 PMCID: PMC9116443 DOI: 10.1039/d1tb02483c] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2021] [Accepted: 03/13/2022] [Indexed: 01/02/2023]
Abstract
New preservation technologies may allow for organ banking similar to blood and biomaterial banking approaches. Using cryoprotective agents (CPAs), aqueous solutions with organic components such as DMSO, propylene glycol, and added salts and sugars, organs can be used to vitrify and store organs at -140 °C. When needed, these organs can be rewarmed in a rapid and uniform manner if CPAs are supplemented with iron oxide nanoparticles (IONPs) in an applied radiofrequency field. Speed and uniformity of warming are both IONP concentration and CPA suspension dependent. Here we present a coating method of small molecule phosphonate linker (PLink) and biocompatible polymer (i.e. polyethylene glycol PEG) that tunes stability and increases the maximum allowable concentration of IONPs in CPA suspension. PLink contains a phosphonate 'anchor' for high irreversible binding to iron oxide and a carboxylic acid 'handle' for ligand attachment. PLink-PEG removes and replaces the initial coating layer of commercially available IONPs (EMG1200 (hydrophobic) and EMG308 (hydrophilic) Ferrotec, Inc., increasing colloidal stability and decreasing aggregation in both water and CPAs, (verified with dynamic light scattering) from minutes (uncoated) to up to 6 days. Heating properties of EMG1200, specific absorption rate (SAR), measured using an applied field of 360 kHz and 20 kA m-1, increased from 20 to 180 W per g Fe with increasing PLink-PEG5000. PEG replacing the initially hydrophobic coating decreased aggregation in water and CPA, consistent with earlier studies on heating performance. Furthermore, although the size is minimized at 0.20 mol PEG per g Fe, heating is not maximized until concentrations above 0.43 mol PEG per g Fe on EMG1200. SAR on hydrophilic EMG308 was preserved at 400 W per g Fe regardless of the amount of PLink added to the core. Herein concentrations of IONP in VS55 (common CPA) significantly above our previous capabilities, sIONP at 10 mg Fe per mL, was reached, 25 mg Fe per mL of 308-PEG5000 and 60 mg Fe per mL of 1200-PEG5000, approaching stock EMG308 in water, 60 mg Fe per mL. Furthermore, at these concentrations cryopreserved Human dermal fibroblast cells were successfully nanowarmed (at applied fields described above), with higher viability as compared to convective rewarming in a water bath and heating rate close to 200 °C min-1, 2.5 times faster than our current system. Using PLink as the coating method allowed for higher concentrations of IONPs to be successfully suspended in CPA without affecting the heating ability. Additionally, the model ligand, PEG, allowed for increased stability over time in nanowarming experiments.
Collapse
Affiliation(s)
- Jacqueline L Pasek-Allen
- Department of Biomedical Engineering, University of Minnesota, 312 Church St. SE, Minneapolis, MN 55455, USA.
| | - Randall K Wilharm
- Department of Chemistry, University of Minnesota, 207 Pleasant St SE, Minneapolis, MN 55455, USA.
| | - Zhe Gao
- Mechanical Engineering, University of Minnesota, 111 Church Street Se, Minneapolis, MN 55455, USA.
| | - Valerie C Pierre
- Department of Chemistry, University of Minnesota, 207 Pleasant St SE, Minneapolis, MN 55455, USA.
| | - John C Bischof
- Department of Biomedical Engineering, University of Minnesota, 312 Church St. SE, Minneapolis, MN 55455, USA.
- Mechanical Engineering, University of Minnesota, 111 Church Street Se, Minneapolis, MN 55455, USA.
| |
Collapse
|
4
|
Jiang Y, Lee J, Seo JM, Davaa E, Shin KJ, Yang SG. Enhanced thermodynamic, pharmacokinetic and theranostic properties of polymeric micelles via hydrophobic core-clustering of superparamagnetic iron oxide nanoparticles. Biomater Res 2022; 26:8. [PMID: 35256008 PMCID: PMC8900364 DOI: 10.1186/s40824-022-00255-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2021] [Accepted: 02/17/2022] [Indexed: 11/18/2022] Open
Abstract
Background Superparamagnetic iron oxide nanoparticles (SPIO) have been applied for decades to design theranostic polymeric micelles for targeted cancer therapy and diagnostic MR imaging. However, the effects of SPIO on the physicochemical, and biological properties of polymeric micelles have not yet been fully elucidated. Therefore, we investigated potential effect of SPIO on the physical and biological properties of theranostic polymeric micelles using representative cancer drug (doxorubicin; Doxo) and polymer carrier (i.e., poly (ethylene glycol)-co-poly(D,L-lactide), PEG-PLA). Methods SPIO were synthesized from Fe(acetyl acetonate)3 in an aryl ether. SPIO and Doxo were loaded into the polymeric micelles by a solvent-evaporation method. We observed the effect of SPIO-clustering on drug loading, micelle size, thermodynamic stability, and theranostic property of PEG-PLA polymeric micelles. In addition, cellular uptake behaviors, pharmacokinetic and biodistribution study were performed. Results SPIO formed hydrophobic geometric cavity in the micelle core and significantly affected the integrity of micelles in terms of micelle size, Doxo loading, critical micelle concentration (CMC) and in vitro dissociation. In vivo pharmacokinetic studies also showed the enhanced Area Under Curve (AUC) and elongated the half-life of Doxo. Conclusions Clustered SPIO in micelles largely affects not only MR imaging properties but also biological and physical properties of polymeric micelles. Supplementary Information The online version contains supplementary material available at 10.1186/s40824-022-00255-9.
Collapse
|
5
|
Greytak AB, Abiodun SL, Burrell JM, Cook EN, Jayaweera NP, Islam MM, Shaker AE. Thermodynamics of nanocrystal–ligand binding through isothermal titration calorimetry. Chem Commun (Camb) 2022; 58:13037-13058. [DOI: 10.1039/d2cc05012a] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Manipulations of nanocrystal (NC) surfaces have propelled the applications of colloidal NCs across various fields such as bioimaging, catalysis, electronics, and sensing applications.
Collapse
Affiliation(s)
- Andrew B. Greytak
- Department of Chemistry and Biochemistry, University of South Carolina, Columbia, South Carolina 29208, USA
| | - Sakiru L. Abiodun
- Department of Chemistry and Biochemistry, University of South Carolina, Columbia, South Carolina 29208, USA
| | - Jennii M. Burrell
- Department of Chemistry and Biochemistry, University of South Carolina, Columbia, South Carolina 29208, USA
| | - Emily N. Cook
- Department of Chemistry and Biochemistry, University of South Carolina, Columbia, South Carolina 29208, USA
| | - Nuwanthaka P. Jayaweera
- Department of Chemistry and Biochemistry, University of South Carolina, Columbia, South Carolina 29208, USA
| | - Md Moinul Islam
- Department of Chemistry and Biochemistry, University of South Carolina, Columbia, South Carolina 29208, USA
| | - Abdulla E Shaker
- Department of Chemistry and Biochemistry, University of South Carolina, Columbia, South Carolina 29208, USA
| |
Collapse
|
6
|
Oberhausen B, Kickelbick G. Induction heating induced self-healing of nanocomposites based on surface-functionalized cationic iron oxide particles and polyelectrolytes. NANOSCALE ADVANCES 2021; 3:5589-5604. [PMID: 36133272 PMCID: PMC9417805 DOI: 10.1039/d1na00417d] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/02/2021] [Accepted: 08/05/2021] [Indexed: 06/16/2023]
Abstract
Supramolecular interactions represent versatile, reversible, and intrinsic mechanisms for bond formation after the failure of materials. Ionic interactions excel through high flexibility and binding strength. In this study, ionic interactions between polymer matrices and inorganic nanoparticles were used to induce self-healing properties. Random, anionic polyelectrolyte copolymers consisting of di(ethylene glycol) methyl ether methacrylate and sodium-4-(methacryloyloxy)butan-1-sulfonate were synthesized by atom transfer radical polymerization. Differential scanning calorimetry measurements confirmed the adjustability of the glass transition temperature via the polymer composition. Within the glass transition temperature window of the homopolymers from -23 °C to 126 °C, the range between -18 °C to 50 °C was examined, generating suitable matrices for self-healing. Superparamagnetic iron oxide nanoparticles with a size of 8 nm were synthesized by thermal decomposition of iron(iii) acetylacetonate and used as the inorganic filler. Positive surface charges were introduced by functionalization with N,N,N-trimethyl-6-phosphonhexan-1-aminium bromide. Functionalization was confirmed with FTIR, TGA, and zeta potential measurements. Ionic interactions between filler and polymer promote a uniform particle dispersion within the material. Self-healing experiments were performed at 80 °C and without the addition of further healing agents. Utilizing the magnetic properties induced by the iron oxide nanoparticles, spatially resolved healing within an alternating magnetic field was achieved on a μm scale.
Collapse
Affiliation(s)
- Bastian Oberhausen
- Saarland University, Inorganic Solid-State Chemistry Campus, Building C4.1 66123 Saarbrücken Germany
| | - Guido Kickelbick
- Saarland University, Inorganic Solid-State Chemistry Campus, Building C4.1 66123 Saarbrücken Germany
| |
Collapse
|
7
|
Mourdikoudis S, Kostopoulou A, LaGrow AP. Magnetic Nanoparticle Composites: Synergistic Effects and Applications. ADVANCED SCIENCE (WEINHEIM, BADEN-WURTTEMBERG, GERMANY) 2021; 8:2004951. [PMID: 34194936 PMCID: PMC8224446 DOI: 10.1002/advs.202004951] [Citation(s) in RCA: 32] [Impact Index Per Article: 10.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/22/2020] [Indexed: 05/17/2023]
Abstract
Composite materials are made from two or more constituent materials with distinct physical or chemical properties that, when combined, produce a material with characteristics which are at least to some degree different from its individual components. Nanocomposite materials are composed of different materials of which at least one has nanoscale dimensions. Common types of nanocomposites consist of a combination of two different elements, with a nanoparticle that is linked to, or surrounded by, another organic or inorganic material, for example in a core-shell or heterostructure configuration. A general family of nanoparticle composites concerns the coating of a nanoscale material by a polymer, SiO2 or carbon. Other materials, such as graphene or graphene oxide (GO), are used as supports forming composites when nanoscale materials are deposited onto them. In this Review we focus on magnetic nanocomposites, describing their synthetic methods, physical properties and applications. Several types of nanocomposites are presented, according to their composition, morphology or surface functionalization. Their applications are largely due to the synergistic effects that appear thanks to the co-existence of two different materials and to their interface, resulting in properties often better than those of their single-phase components. Applications discussed concern magnetically separable catalysts, water treatment, diagnostics-sensing and biomedicine.
Collapse
Affiliation(s)
- Stefanos Mourdikoudis
- Biophysics GroupDepartment of Physics and AstronomyUniversity College LondonLondonWC1E 6BTUK
- UCL Healthcare Biomagnetic and Nanomaterials Laboratories21 Albemarle StreetLondonW1S 4BSUK
| | - Athanasia Kostopoulou
- Institute of Electronic Structure and Laser (IESL)Foundation for Research and Technology‐Hellas (FORTH)100 Nikolaou PlastiraHeraklionCrete70013Greece
| | - Alec P. LaGrow
- International Iberian Nanotechnology LaboratoryBraga4715‐330Portugal
| |
Collapse
|
8
|
Zhang Q, Pratt EC, Tamura R, Ogirala A, Hsu C, Farahmand N, O’Brien S, Grimm J. Ultrasmall Downconverting Nanoparticle for Enhanced Cerenkov Imaging. NANO LETTERS 2021; 21:4217-4224. [PMID: 33950695 PMCID: PMC8879088 DOI: 10.1021/acs.nanolett.1c00049] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
Cerenkov imaging provides an opportunity to expand the application of approved radiotracers and therapeutic agents by utilizing them for optical approaches, which opens new avenues for nuclear imaging. The dominating Cerenkov radiation is in the UV/blue region, where it is readily absorbed by human tissue, reducing its utility in vivo. To solve this problem, we propose a strategy to shift Cerenkov light to the more penetrative red-light region through the use of a fluorescent down-conversion technique, based upon europium oxide nanoparticles. We synthesized square-shape ultrasmall Eu2O3 nanoparticles, functionalized with polyethylene glycol and chelate-free radiolabeled for intravenous injection into mice to visualize the lymph node and tumor. By adding trimethylamine N-oxide during the synthesis, we significantly increased the brightness of the particle and synthesized the (to-date) smallest radiolabeled europium-based nanoparticle. These features allow for the exploration of Eu2O3 nanoparticles as a preclinical cancer diagnosis platform with multimodal imaging capability.
Collapse
Affiliation(s)
- Qize Zhang
- Molecular Pharmacology Program, Memorial Sloan Kettering Cancer Center, New York, NY 10065, USA
- Department of Chemistry and Biochemistry, The City College of New York, 1024 Marshak, 160 Convent Avenue, New York, New York 10031, USA
- Ph.D. Program in Chemistry, The Graduate Center of the City University of New York, New York, New York 10016, USA
| | - Edwin C. Pratt
- Department of Radiology, Memorial Sloan Kettering Cancer Center, New York, NY 10065, USA
- Department of Pharmacology, Weill Cornell Medical College, New York, NY 10021, USA
| | - Ryo Tamura
- Molecular Pharmacology Program, Memorial Sloan Kettering Cancer Center, New York, NY 10065, USA
- Department of Radiology, Memorial Sloan Kettering Cancer Center, New York, NY 10065, USA
| | - Anuja Ogirala
- Molecular Pharmacology Program, Memorial Sloan Kettering Cancer Center, New York, NY 10065, USA
| | - Charlene Hsu
- Molecular Pharmacology Program, Memorial Sloan Kettering Cancer Center, New York, NY 10065, USA
| | - Nasim Farahmand
- Department of Chemistry and Biochemistry, The City College of New York, 1024 Marshak, 160 Convent Avenue, New York, New York 10031, USA
- Ph.D. Program in Chemistry, The Graduate Center of the City University of New York, New York, New York 10016, USA
| | - Stephen O’Brien
- Department of Chemistry and Biochemistry, The City College of New York, 1024 Marshak, 160 Convent Avenue, New York, New York 10031, USA
- Ph.D. Program in Chemistry, The Graduate Center of the City University of New York, New York, New York 10016, USA
| | - Jan Grimm
- Molecular Pharmacology Program, Memorial Sloan Kettering Cancer Center, New York, NY 10065, USA
- Department of Radiology, Memorial Sloan Kettering Cancer Center, New York, NY 10065, USA
- Department of Pharmacology, Weill Cornell Medical College, New York, NY 10021, USA
- Department of Radiology, Weill Cornell Medical College, New York, NY 10021, USA
| |
Collapse
|
9
|
Jang J, Song SH, Kim H, Moon J, Ahn H, Jo KI, Bang J, Kim H, Koo J. Janus Graphene Oxide Sheets with Fe 3O 4 Nanoparticles and Polydopamine as Anodes for Lithium-Ion Batteries. ACS APPLIED MATERIALS & INTERFACES 2021; 13:14786-14795. [PMID: 33739082 DOI: 10.1021/acsami.1c02892] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
In this study, a one-step process to fabricate "Janus"-structured nanocomposites with iron oxide (Fe3O4) nanoparticles (Fe3O4 NPs) and polydopamine (PDA) on each side of a graphene oxide (GO) nanosheet using the Langmuir-Schaefer technique has been proposed. The Fe3O4 NPs-GO hybrid is used as a high-capacity active material, while PDA is added as a binder due to its unique wet-resistant adhesive property. The transmission electron microscopy image shows a superlattice-like out-of-plane section of the multilayered nanocomposite, which maximizes the density of the composite materials. Grazing-incidence small-angle X-ray scattering results combined with scanning electron microscopy images confirm that the multilayered Janus composite exhibits an in-plane hexagonal array structure of closely packed Fe3O4 NPs. This Janus multilayered structure is expected to maximize the amount of active material in a specific volume and reduce volume changes caused by the conversion reaction of Fe3O4 NPs. According to the electrochemical results, the Janus multilayer electrode delivers an excellent capacity of ∼903 mAh g-1 at a current density of 200 mA g-1 and a reversible capacity of ∼639 mAh g-1 at 1 A g-1 up to the 1800th cycle, indicating that this Janus composite can be a promising anode for Li-ion batteries.
Collapse
Affiliation(s)
- Jiwon Jang
- Department of Organic Material Engineering, Chungnam National University, Daejeon 34134, Korea
| | - Seok Hyun Song
- Neutron Science Division, Korea Atomic Energy Research Institute (KAERI), Daejeon 34057, Korea
- Department of Chemical and Biological Engineering, Korea University, Seoul 02841, Korea
| | - Hyeri Kim
- Department of Organic Material Engineering, Chungnam National University, Daejeon 34134, Korea
| | - Junsoo Moon
- Department of Chemical and Biological Engineering, Korea University, Seoul 02841, Korea
| | - Hyungju Ahn
- Pohang Accelerator Laboratory (PAL), Pohang University of Science and Technology, Pohang 37673, Korea
| | - Kyoung-Il Jo
- Neutron Science Division, Korea Atomic Energy Research Institute (KAERI), Daejeon 34057, Korea
- Department of Chemical and Biological Engineering, Korea University, Seoul 02841, Korea
| | - Joona Bang
- Department of Chemical and Biological Engineering, Korea University, Seoul 02841, Korea
| | - Hyungsub Kim
- Neutron Science Division, Korea Atomic Energy Research Institute (KAERI), Daejeon 34057, Korea
| | - Jaseung Koo
- Department of Organic Material Engineering, Chungnam National University, Daejeon 34134, Korea
| |
Collapse
|
10
|
Moura NS, Bajgiran KR, Roman CL, Daemen L, Cheng Y, Lawrence J, Melvin AT, Dooley KM, Dorman JA. Catalytic Enhancement of Inductively Heated Fe 3 O 4 Nanoparticles by Removal of Surface Ligands. CHEMSUSCHEM 2021; 14:1122-1130. [PMID: 33338322 DOI: 10.1002/cssc.202002775] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/01/2020] [Indexed: 06/12/2023]
Abstract
Heat management in catalysis is limited by each material's heat transfer efficiencies, resulting in energy losses despite current thermal engineering strategies. In contrast, induction heating of magnetic nanoparticles (NPs) generates heat at the surface of the catalyst where the reaction occurs, reducing waste heat via dissipation. However, the synthesis of magnetic NPs with optimal heat generation requires interfacial ligands, such as oleic acid, which act as heat sinks. Surface treatments using tetramethylammonium hydroxide (TMAOH) or pyridine are used to remove these ligands before applications in hydrophilic media. In this study, Fe3 O4 NPs are surface treated to study the effect of induction heating on the catalytic oxidation of 1-octanol. Whereas TMAOH was unsuccessful in removing oleic acid, pyridine treatment resulted in a roughly 2.5-fold increase in heat generation and product yield. Therefore, efficient surfactant removal has profound implications in induction heating catalysis by increasing the heat transfer and available surface sites.
Collapse
Affiliation(s)
- Natalia S Moura
- Department of Chemical Engineering, Louisiana State University, 3307 Patrick F. Taylor Hall, Baton Rouge, LA 70803, USA
| | - Khashayar R Bajgiran
- Department of Chemical Engineering, Louisiana State University, 3307 Patrick F. Taylor Hall, Baton Rouge, LA 70803, USA
| | - Cameron L Roman
- Department of Chemical Engineering, Louisiana State University, 3307 Patrick F. Taylor Hall, Baton Rouge, LA 70803, USA
| | - Luke Daemen
- Spallation Neutron Source, Oak Ridge National Lab, PO. Box 2008, Oak Ridge, TN 37831, USA
| | - Yongqiang Cheng
- Spallation Neutron Source, Oak Ridge National Lab, PO. Box 2008, Oak Ridge, TN 37831, USA
| | - Jimmy Lawrence
- Department of Chemical Engineering, Louisiana State University, 3307 Patrick F. Taylor Hall, Baton Rouge, LA 70803, USA
| | - Adam T Melvin
- Department of Chemical Engineering, Louisiana State University, 3307 Patrick F. Taylor Hall, Baton Rouge, LA 70803, USA
| | - Kerry M Dooley
- Department of Chemical Engineering, Louisiana State University, 3307 Patrick F. Taylor Hall, Baton Rouge, LA 70803, USA
| | - James A Dorman
- Department of Chemical Engineering, Louisiana State University, 3307 Patrick F. Taylor Hall, Baton Rouge, LA 70803, USA
| |
Collapse
|
11
|
He S, Kickelbick G. Reversible Diels-Alder Reactions with a Fluorescent Dye on the Surface of Magnetite Nanoparticles. Molecules 2021; 26:molecules26040877. [PMID: 33562273 PMCID: PMC7916023 DOI: 10.3390/molecules26040877] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2020] [Revised: 02/03/2021] [Accepted: 02/04/2021] [Indexed: 01/01/2023] Open
Abstract
Diels–Alder reactions on the surface of nanoparticles allow a thermoreversible functionalization of the nanosized building blocks. We report the synthesis of well-defined magnetite nanoparticles by thermal decomposition reaction and their functionalization with maleimide groups. Attachment of these dienophiles was realized by the synthesis of organophosphonate coupling agents and a partial ligand exchange of the original carboxylic acid groups. The functionalized iron oxide particles allow a covalent surface attachment of a furfuryl-functionalized rhodamine B dye by a Diels–Alder reaction at 60 °C. The resulting particles showed the typical fluorescence of rhodamine B. The dye can be cleaved off the particle surface by a retro-Diels–Alder reaction. The study showed that organic functions can be thermoreversibly attached onto inorganic nanoparticles.
Collapse
|
12
|
Cheah P, Brown P, Qu J, Tian B, Patton DL, Zhao Y. Versatile Surface Functionalization of Water-Dispersible Iron Oxide Nanoparticles with Precisely Controlled Sizes. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2021; 37:1279-1287. [PMID: 33434432 DOI: 10.1021/acs.langmuir.0c03314] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
The synthesis of highly water-dispersible iron oxide nanoparticles with surface functional groups and precisely controlled sizes is essential for biomedical application. In this paper, we report a one-pot strategy for versatile surface functionalization. The iron oxide nanoparticles are first synthesized by thermal decomposition of iron(III) acetylacetonate (Fe(acac)3) in diethylene glycol (DEG), and their surfaces are modified by adding the surface ligands at the end of the reaction. The size of iron oxide nanoparticles can be precisely controlled in nanometer scale by continuous growth. This facile synthesis method enables the surface modification with different coating materials such as dopamine (DOPA), polyethylene glycol with thiol end group (thiol-PEG), and poly(acrylic acid) (PAA) onto the iron oxide nanoparticles, introducing new surface functionalities for future biomedical application. From transmission electron microscopy (TEM) and X-ray diffraction (XRD), the morphology and crystal structure are not changed during surface functionalization. The attachment of surface ligands is studied by Fourier transform infrared spectroscopy (FTIR) and Thermogravimetric Analysis (TGA). The surface functional groups are confirmed by X-ray Photoelectron Spectroscopy (XPS). In correlation with the change of hydrodynamic size, PAA coated nanoparticles are found to exhibit outstanding stability in aqueous solution. Furthermore, we demonstrate that the functional groups are available for conjugating with other molecules such as fluorescent dye, showing potential biological applications. Lastly, the magnetic resonance phantom studies demonstrate that iron oxide nanoparticles with PAA coating can be used as T1 and T2 dual-modality contrast agents. Both r1 and r2 relaxivities significantly increase after surface functionalization with PAA, indicating improved sensitivity.
Collapse
Affiliation(s)
- Pohlee Cheah
- Department of Chemistry, Physics, and Atmospheric Science, Jackson State University, Jackson, Mississippi 39217, United States
| | - Paul Brown
- Department of Chemistry, Physics, and Atmospheric Science, Jackson State University, Jackson, Mississippi 39217, United States
| | - Jing Qu
- Department of Chemistry, Physics, and Atmospheric Science, Jackson State University, Jackson, Mississippi 39217, United States
| | - Bin Tian
- Department of Chemistry, Physics, and Atmospheric Science, Jackson State University, Jackson, Mississippi 39217, United States
| | - Derek L Patton
- School of Polymer Science and Engineering, University of Southern Mississippi, Hattiesburg, Mississippi 39406, United States
| | - Yongfeng Zhao
- Department of Chemistry, Physics, and Atmospheric Science, Jackson State University, Jackson, Mississippi 39217, United States
| |
Collapse
|
13
|
Xu S, Wang J, Wei Y, Zhao H, Tao T, Wang H, Wang Z, Du J, Wang H, Qian J, Ma K, Wang J. In Situ One-Pot Synthesis of Fe 2O 3@BSA Core-Shell Nanoparticles as Enhanced T 1-Weighted Magnetic Resonance Imagine Contrast Agents. ACS APPLIED MATERIALS & INTERFACES 2020; 12:56701-56711. [PMID: 33296181 DOI: 10.1021/acsami.0c13825] [Citation(s) in RCA: 25] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
Ultra-small-sized iron oxide nanoparticles with good biocompatibility are regarded as promising alternatives for the gadolinium-based contrast agents, which are widely used as a positive contrast agent in magnetic resonance imaging (MRI). However, the current preparation of the iron oxide magnetic nanoparticles with small sizes usually involves organic solvents, increasing the complexity of hydrophilic ligand replacement and reducing the synthesis efficiency. It remains a great challenge to explore new iron oxide nanoparticles with good biocompatibility and a high T1 contrast effect. Here, we reported a cage-like protein architecture self-assembled by approximately 6-7 BSA (bovine serum albumin) subunits. The BSA nanocage was then used as a biotemplate to synthesize uniformed and monodispersed Fe2O3@BSA nanoparticles with ultra-small sizes (∼3.5 nm). The Fe2O3@BSA nanoparticle showed a high r1 value of 6.8 mM-1 s-1 and a low r2/r1 ratio of 10.6 at a 3 T magnetic field. Compared to Gd-DTPA, the brighter signal and prolonged angiographic effect of Fe2O3@BSA nanoparticles could greatly benefit steady-state and high-resolution imaging. The further in vivo and in vitro assessments of stability, toxicity, and renal clearance indicated a substantial potential as a T1 contrast agent in preclinical MRI.
Collapse
Affiliation(s)
- Shuai Xu
- High Magnetic Field Laboratory, CAS Key Laboratory of High Magnetic Field and Ion Beam Physical Biology, Hefei Institutes of Physical Science, Chinese Academy of Sciences, Hefei 230031, P.R. China
- University of Science and Technology of China, Hefei 230036, P.R. China
| | - Jiarong Wang
- High Magnetic Field Laboratory, CAS Key Laboratory of High Magnetic Field and Ion Beam Physical Biology, Hefei Institutes of Physical Science, Chinese Academy of Sciences, Hefei 230031, P.R. China
| | - Yuan Wei
- School of Basic Medical Sciences, Anhui Medical University, Hefei 230032, P.R. China
| | - Hongxin Zhao
- High Magnetic Field Laboratory, CAS Key Laboratory of High Magnetic Field and Ion Beam Physical Biology, Hefei Institutes of Physical Science, Chinese Academy of Sciences, Hefei 230031, P.R. China
| | - Tongxiang Tao
- High Magnetic Field Laboratory, CAS Key Laboratory of High Magnetic Field and Ion Beam Physical Biology, Hefei Institutes of Physical Science, Chinese Academy of Sciences, Hefei 230031, P.R. China
- University of Science and Technology of China, Hefei 230036, P.R. China
| | - Hui Wang
- High Magnetic Field Laboratory, CAS Key Laboratory of High Magnetic Field and Ion Beam Physical Biology, Hefei Institutes of Physical Science, Chinese Academy of Sciences, Hefei 230031, P.R. China
| | - Zhen Wang
- High Magnetic Field Laboratory, CAS Key Laboratory of High Magnetic Field and Ion Beam Physical Biology, Hefei Institutes of Physical Science, Chinese Academy of Sciences, Hefei 230031, P.R. China
- University of Science and Technology of China, Hefei 230036, P.R. China
| | - Juan Du
- School of Basic Medical Sciences, Anhui Medical University, Hefei 230032, P.R. China
| | - Hongzhi Wang
- Hefei Cancer Hospital, Anhui Province Key Laboratory of Medical Physics and Technology, Institute of Health and Medical Technology, Hefei Institutes of Physical Science, Chinese Academy of Sciences, Hefei 230031, P.R. China
| | - Junchao Qian
- Hefei Cancer Hospital, Anhui Province Key Laboratory of Medical Physics and Technology, Institute of Health and Medical Technology, Hefei Institutes of Physical Science, Chinese Academy of Sciences, Hefei 230031, P.R. China
| | - Kun Ma
- High Magnetic Field Laboratory, CAS Key Laboratory of High Magnetic Field and Ion Beam Physical Biology, Hefei Institutes of Physical Science, Chinese Academy of Sciences, Hefei 230031, P.R. China
| | - Junfeng Wang
- High Magnetic Field Laboratory, CAS Key Laboratory of High Magnetic Field and Ion Beam Physical Biology, Hefei Institutes of Physical Science, Chinese Academy of Sciences, Hefei 230031, P.R. China
- University of Science and Technology of China, Hefei 230036, P.R. China
- Institutes of Physical Science and Information Technology, Anhui University, Hefei, Anhui 230601, P.R. China
| |
Collapse
|
14
|
Modulating the interfacial properties of magnetic nanoparticles through surface modification with a binary polymer mixture towards stabilization of double emulsions. Colloids Surf A Physicochem Eng Asp 2020. [DOI: 10.1016/j.colsurfa.2019.124208] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
|
15
|
Lee DY, Kang S, Lee Y, Kim JY, Yoo D, Jung W, Lee S, Jeong YY, Lee K, Jon S. PEGylated Bilirubin-coated Iron Oxide Nanoparticles as a Biosensor for Magnetic Relaxation Switching-based ROS Detection in Whole Blood. Theranostics 2020; 10:1997-2007. [PMID: 32104497 PMCID: PMC7019166 DOI: 10.7150/thno.39662] [Citation(s) in RCA: 21] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2019] [Accepted: 12/16/2019] [Indexed: 12/13/2022] Open
Abstract
Rationale: Magnetic relaxation switching (MRSw) induced by target-triggered aggregation or dissociation of superparamagnetic iron oxide nanoparticles (SPIONs) have been utilized for detection of diverse biomarkers. However, an MRSw-based biosensor for reactive oxygen species (ROS) has never been documented. Methods: To this end, we constructed a biosensor for ROS detection based on PEGylated bilirubin (PEG-BR)-coated SPIONs (PEG-BR@SPIONs) that were prepared by simple sonication via ligand exchange. In addition, near infra-red (NIR) fluorescent dye was loaded onto PEG-BR@SPIONs as a secondary option for fluorescence-based ROS detection. Results: PEG-BR@SPIONs showed high colloidal stability under physiological conditions, but upon exposure to the model ROS, NaOCl, in vitro, they aggregated, causing a decrease in signal intensity in T2-weighted MR images. Furthermore, ROS-responsive PEG-BR@SPIONs were taken up by lipopolysaccharide (LPS)-activated macrophages to a much greater extent than ROS-unresponsive control nanoparticles (PEG-DSPE@SPIONs). In a sepsis-mimetic clinical setting, PEG-BR@SPIONs were able to directly detect the concentrations of ROS in whole blood samples through a clear change in T2 MR signals and a 'turn-on' signal of fluorescence. Conclusions: These findings suggest that PEG-BR@SPIONs have the potential as a new type of dual mode (MRSw-based and fluorescence-based) biosensors for ROS detection and could be used to diagnose many diseases associated with ROS overproduction.
Collapse
|
16
|
Sandler SE, Fellows B, Mefford OT. Best Practices for Characterization of Magnetic Nanoparticles for Biomedical Applications. Anal Chem 2019; 91:14159-14169. [DOI: 10.1021/acs.analchem.9b03518] [Citation(s) in RCA: 51] [Impact Index Per Article: 10.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Affiliation(s)
- Sarah E. Sandler
- Department of Materials Science and Engineering, Clemson University, Clemson, South Carolina 29634, United States
| | - Benjamin Fellows
- Department of Bioengineering, University of California at Berkeley, Berkeley, California 94720, United States
| | - O. Thompson Mefford
- Department of Materials Science and Engineering, Clemson University, Clemson, South Carolina 29634, United States
| |
Collapse
|
17
|
Schechtel E, Dören R, Frerichs H, Panthöfer M, Mondeshki M, Tremel W. Mixed Ligand Shell Formation upon Catechol Ligand Adsorption on Hydrophobic TiO 2 Nanoparticles. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2019; 35:12518-12531. [PMID: 31487189 DOI: 10.1021/acs.langmuir.9b02496] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
Modifying the surfaces of metal oxide nanoparticles (NPs) with monolayers of ligands provides a simple and direct method to generate multifunctional coatings by altering their surface properties. This works best if the composition of the monolayers can be controlled. Mussel-inspired, noninnocent catecholates stand out from other ligands like carboxylates and amines because they are redox-active and allow for highly efficient surface binding and enhanced electron transfer to the surface. However, a comprehensive understanding of their surface chemistry, including surface coverage and displacement of the native ligand, is still lacking. Here, we unravel the displacement of oleate (OA) ligands on hydrophobic, OA-stabilized TiO2 NPs by catecholate ligands using a combination of one- and two-dimensional nuclear magnetic resonance (NMR) spectroscopy techniques. Conclusive pictures of the ligand shells before and after surface modification with catecholate were obtained by 1H and 13C NMR spectroscopy (the 13C chemical shift being more sensitive and with a broader range). The data could be explained using a Langmuir-type approach. Gradual formation of a mixed ligand shell was observed, and the surface processes of catecholate adsorption and OA desorption were quantified. Contrary to the prevailing view, catecholate displaces only a minor fraction (∼20%) of the native OA ligand shell. At the same time, the total ligand density more than doubled from 2.3 nm-2 at native oleate coverage to 4.8 nm-2 at maximum catecholate loading. We conclude that the catecholate ligand adsorbs preferably to unoccupied Ti surface sites rather than replacing native OA ligands. This unexpected behavior, reminiscent of the Vroman effect for protein corona formation, appears to be a fundamental feature in the widely used surface modification of hydrophobic metal oxide NPs with catecholate ligands. Moreover, our findings show that ligand displacement on OA-capped TiO2 NPs is not suited for a full ligand shell refunctionalization because it produces only mixed ligand shells. Therefore, our results contribute to a better understanding and performance of photocatalytic applications based on catecholate ligand-sensitized TiO2 NPs.
Collapse
Affiliation(s)
- Eugen Schechtel
- Institut für Anorganische Chemie und Analytische Chemie , Johannes Gutenberg-Universität Mainz , Duesbergweg 10-14 , D-55128 Mainz , Germany
| | - René Dören
- Institut für Anorganische Chemie und Analytische Chemie , Johannes Gutenberg-Universität Mainz , Duesbergweg 10-14 , D-55128 Mainz , Germany
| | - Hajo Frerichs
- Institut für Anorganische Chemie und Analytische Chemie , Johannes Gutenberg-Universität Mainz , Duesbergweg 10-14 , D-55128 Mainz , Germany
| | - Martin Panthöfer
- Institut für Anorganische Chemie und Analytische Chemie , Johannes Gutenberg-Universität Mainz , Duesbergweg 10-14 , D-55128 Mainz , Germany
| | - Mihail Mondeshki
- Institut für Anorganische Chemie und Analytische Chemie , Johannes Gutenberg-Universität Mainz , Duesbergweg 10-14 , D-55128 Mainz , Germany
| | - Wolfgang Tremel
- Institut für Anorganische Chemie und Analytische Chemie , Johannes Gutenberg-Universität Mainz , Duesbergweg 10-14 , D-55128 Mainz , Germany
| |
Collapse
|
18
|
Reimhult E, Schroffenegger M, Lassenberger A. Design Principles for Thermoresponsive Core-Shell Nanoparticles: Controlling Thermal Transitions by Brush Morphology. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2019; 35:7092-7104. [PMID: 31035760 PMCID: PMC6551573 DOI: 10.1021/acs.langmuir.9b00665] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/05/2019] [Revised: 04/17/2019] [Indexed: 05/15/2023]
Abstract
In this feature article, we summarize our recent work on understanding and controlling the thermal behavior of nanoparticles grafted with thermoresponsive polymer shells. Precision synthesis of monodisperse superparamagnetic iron oxide nanocrystals was combined with irreversible dense grafting of nitrodopamide-anchored thermoresponsive polymer chains. We provide an overview of how the dense and stable grafting of biomedically relevant polymers, including poly(ethylene glycol), poly( N-isopropylacrylamide), polysarcosin, and polyoxazolines, can be achieved. This platform has made it possible for us to demonstrate that the polymer brush geometry, as defined by the nanoparticle core and relative polymer brush size, determines the thermal transitions of the polymer brush. We furthermore summarize our work on how the polymer shell transitions and nanoparticle aggregation can be tuned. With the independent variation of the core and the shell, we can optimize and precisely control the thermally controlled solubility of our system. Finally, our feature article gives examples relevant to current and future applications. We show how the thermal response of the shell influences the nanoparticle performance in biological fluids and interactions with proteins and cells, also under purely magnetic actuation of the nanoparticles through the superparamagnetic iron oxide core.
Collapse
Affiliation(s)
- Erik Reimhult
- Institute
for Biologically Inspired Materials, Department of Nanobiotechnology, University of Natural Resources and Life Sciences, Muthgasse 11, 1190 Vienna, Austria
| | - Martina Schroffenegger
- Institute
for Biologically Inspired Materials, Department of Nanobiotechnology, University of Natural Resources and Life Sciences, Muthgasse 11, 1190 Vienna, Austria
| | | |
Collapse
|
19
|
Wei N, Li L, Zhang H, Wang W, Pan C, Qi S, Zhang H, Chen H, Chen X. Characterization of the Ligand Exchange Reactions on CdSe/ZnS QDs by Capillary Electrophoresis. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2019; 35:4806-4812. [PMID: 30865827 DOI: 10.1021/acs.langmuir.8b03856] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
The continuous development of semiconductor quantum dots (QDs) in biochemical research has attracted special attention, and surface functionalizing becomes more important to optimize their performance. Ligand exchange reactions are commonly used to modify the surface of QDs for their biomedical applications. However, the kinetics of ligand exchange for semiconductor QDs remain fully unexplored. Here, we describe a simple and rapid method to characterize the ligand exchange reactions on CdSe/ZnS QDs by capillary electrophoresis (CE). The results of ultraviolet-visible absorption spectra, fluorescence spectra, and Fourier transform infrared spectroscopy indicated the successful implementation of the ligand exchange process. The dynamics of ligand exchange of OA-coated CdSe/ZnS QDs with 4-mercaptobenzoic acid was monitored by CE, and the observed ligand exchange trends were fitted with logistic functions. When the ligand exchange reactions reached equilibrium, the ligand density of QDs can be quantified by CE. It is anticipated that CE will be a new powerful technique for quantitative analysis of the ligand exchange reactions on the surface of QDs.
Collapse
Affiliation(s)
- Nannan Wei
- State Key Laboratory of Applied Organic Chemistry, College of Chemistry and Chemical Engineering, Key Laboratory of Nonferrous Metal Chemistry and Resources Utilization of Gansu Province , Lanzhou University , Lanzhou 730000 , China
| | - Ling Li
- State Key Laboratory of Applied Organic Chemistry, College of Chemistry and Chemical Engineering, Key Laboratory of Nonferrous Metal Chemistry and Resources Utilization of Gansu Province , Lanzhou University , Lanzhou 730000 , China
| | - Huige Zhang
- State Key Laboratory of Applied Organic Chemistry, College of Chemistry and Chemical Engineering, Key Laboratory of Nonferrous Metal Chemistry and Resources Utilization of Gansu Province , Lanzhou University , Lanzhou 730000 , China
| | - Weifeng Wang
- Lanzhou Institute of Chemical Physics , Chinese Academy of Sciences , Lanzhou 730000 , P. R. China
| | - Congjie Pan
- State Key Laboratory of Applied Organic Chemistry, College of Chemistry and Chemical Engineering, Key Laboratory of Nonferrous Metal Chemistry and Resources Utilization of Gansu Province , Lanzhou University , Lanzhou 730000 , China
| | - Shengda Qi
- State Key Laboratory of Applied Organic Chemistry, College of Chemistry and Chemical Engineering, Key Laboratory of Nonferrous Metal Chemistry and Resources Utilization of Gansu Province , Lanzhou University , Lanzhou 730000 , China
| | - Hongyi Zhang
- Key Laboratory of Analytical Science and Technology of Hebei Province, College of Chemistry and Environmental Science , Hebei University , Baoding 071002 , China
| | - Hongli Chen
- State Key Laboratory of Applied Organic Chemistry, College of Chemistry and Chemical Engineering, Key Laboratory of Nonferrous Metal Chemistry and Resources Utilization of Gansu Province , Lanzhou University , Lanzhou 730000 , China
| | - Xingguo Chen
- State Key Laboratory of Applied Organic Chemistry, College of Chemistry and Chemical Engineering, Key Laboratory of Nonferrous Metal Chemistry and Resources Utilization of Gansu Province , Lanzhou University , Lanzhou 730000 , China
| |
Collapse
|
20
|
Koll R, Fruhner LS, Heller H, Allgaier J, Pyckhout-Hintzen W, Kruteva M, Feoktystov A, Biehl R, Förster S, Weller H. Creating a synthetic platform for the encapsulation of nanocrystals with covalently bound polymer shells. NANOSCALE 2019; 11:3847-3854. [PMID: 30758011 DOI: 10.1039/c8nr10018g] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
We present a platform for the encapsulation of superparamagnetic iron oxide nanocrystals (SPIONs) with a highly stable diblock copolymer shell allowing a homogeneous dispersion of the nanocrystals into a polymer matrix in the resulting nanocomposites. High polymer shell stability was achieved by crosslinking the inner polydiene shell for example in a persulfate based redox process. The advantage of this crosslinking reaction is the avoidance of heat and UV light for the initiation, making it suitable for heat or UV sensitive systems. In addition, we were able to minimize the ligand excess needed for the encapsulation and showcased a variation of molecular weight and composition as well as different ligands which lead to stable micelles. The encapsulated nanocrystals as well as the nanocomposite materials were characterized by transmission electron microscopy (TEM) and small angle scattering (SAXS and SANS).
Collapse
Affiliation(s)
- Rieke Koll
- Institute of Physical Chemistry, Fraunhofer CAN, Grindelallee 117, 20146 Hamburg, Germany.
| | - Lisa Sarah Fruhner
- Jülich Centre for Neutron Science (JCNS-1) and Institute for Complex Systems (ICS-1), Forschungszentrum Jülich GmbH, Leo-Brandt-Straße, 52425 Jülich, Germany. and Institute of Physical Chemistry, RWTH Aachen University, Landoltweg 2, 52056 Aachen, Germany
| | - Hauke Heller
- Institute of Physical Chemistry, Fraunhofer CAN, Grindelallee 117, 20146 Hamburg, Germany.
| | - Jürgen Allgaier
- Jülich Centre for Neutron Science (JCNS-1) and Institute for Complex Systems (ICS-1), Forschungszentrum Jülich GmbH, Leo-Brandt-Straße, 52425 Jülich, Germany.
| | - Wim Pyckhout-Hintzen
- Jülich Centre for Neutron Science (JCNS-1) and Institute for Complex Systems (ICS-1), Forschungszentrum Jülich GmbH, Leo-Brandt-Straße, 52425 Jülich, Germany.
| | - Margarita Kruteva
- Jülich Centre for Neutron Science (JCNS-1) and Institute for Complex Systems (ICS-1), Forschungszentrum Jülich GmbH, Leo-Brandt-Straße, 52425 Jülich, Germany.
| | - Artem Feoktystov
- Forschungszentrum Jülich GmbH, Jülich Centre for Neutron Science (JCNS) at MLZ, Lichtenbergstrasse 1, 85748 Garching, Germany
| | - Ralf Biehl
- Jülich Centre for Neutron Science (JCNS-1) and Institute for Complex Systems (ICS-1), Forschungszentrum Jülich GmbH, Leo-Brandt-Straße, 52425 Jülich, Germany.
| | - Stephan Förster
- Jülich Centre for Neutron Science (JCNS-1) and Institute for Complex Systems (ICS-1), Forschungszentrum Jülich GmbH, Leo-Brandt-Straße, 52425 Jülich, Germany. and Institute of Physical Chemistry, RWTH Aachen University, Landoltweg 2, 52056 Aachen, Germany
| | - Horst Weller
- Institute of Physical Chemistry, Fraunhofer CAN, Grindelallee 117, 20146 Hamburg, Germany.
| |
Collapse
|
21
|
Tan L, Liu B, Siemensmeyer K, Glebe U, Böker A. Synthesis of Polystyrene-Coated Superparamagnetic and Ferromagnetic Cobalt Nanoparticles. Polymers (Basel) 2018; 10:E1053. [PMID: 30960978 PMCID: PMC6404081 DOI: 10.3390/polym10101053] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2018] [Revised: 09/13/2018] [Accepted: 09/18/2018] [Indexed: 01/15/2023] Open
Abstract
Polystyrene-coated cobalt nanoparticles (NPs) were synthesized through a dual-stage thermolysis of cobalt carbonyl (Co₂(CO)₈). The amine end-functionalized polystyrene surfactants with varying molecular weight were prepared via atom-transfer radical polymerization technique. By changing the concentration of these polymeric surfactants, Co NPs with different size, size distribution, and magnetic properties were obtained. Transmission electron microscopy characterization showed that the size of Co NPs stabilized with lower molecular weight polystyrene surfactants (Mn = 2300 g/mol) varied from 12⁻22 nm, while the size of Co NPs coated with polystyrene of middle (Mn = 4500 g/mol) and higher molecular weight (Mn = 10,500 g/mol) showed little change around 20 nm. Magnetic measurements revealed that the small cobalt particles were superparamagnetic, while larger particles were ferromagnetic and self-assembled into 1-D chain structures. Thermogravimetric analysis revealed that the grafting density of polystyrene with lower molecular weight is high. To the best of our knowledge, this is the first study to obtain both superparamagnetic and ferromagnetic Co NPs by changing the molecular weight and concentration of polystyrene through the dual-stage decomposition method.
Collapse
Affiliation(s)
- Li Tan
- Fraunhofer Institute for Applied Polymer Research IAP, Geiselbergstr. 69, 14476 Potsdam-Golm, Germany.
- Lehrstuhl für Polymermaterialien und Polymertechnologie, Universität Potsdam, 14476 Potsdam-Golm, Germany.
| | - Bing Liu
- Institute of Chemistry Chinese Academy of Sciences, Beijing 100864, China.
| | | | - Ulrich Glebe
- Fraunhofer Institute for Applied Polymer Research IAP, Geiselbergstr. 69, 14476 Potsdam-Golm, Germany.
| | - Alexander Böker
- Fraunhofer Institute for Applied Polymer Research IAP, Geiselbergstr. 69, 14476 Potsdam-Golm, Germany.
- Lehrstuhl für Polymermaterialien und Polymertechnologie, Universität Potsdam, 14476 Potsdam-Golm, Germany.
| |
Collapse
|
22
|
Fellows BD, Ghobrial N, Mappus E, Hargett A, Bolding M, Dean D, Mefford OT. In vitro studies of heparin-coated magnetic nanoparticles for use in the treatment of neointimal hyperplasia. NANOMEDICINE-NANOTECHNOLOGY BIOLOGY AND MEDICINE 2018. [DOI: 10.1016/j.nano.2018.02.011] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
|
23
|
Optimization of Iron Oxide Tracer Synthesis for Magnetic Particle Imaging. NANOMATERIALS 2018; 8:nano8040180. [PMID: 29561782 PMCID: PMC5923510 DOI: 10.3390/nano8040180] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/23/2018] [Revised: 03/17/2018] [Accepted: 03/19/2018] [Indexed: 12/30/2022]
Abstract
The optimization of iron oxide nanoparticles as tracers for magnetic particle imaging (MPI) alongside the development of data acquisition equipment and image reconstruction techniques is crucial for the required improvements in image resolution and sensitivity of MPI scanners. We present a large-scale water-based synthesis of multicore superparamagnetic iron oxide nanoparticles stabilized with dextran (MC-SPIONs). We also demonstrate the preparation of single core superparamagnetic iron oxide nanoparticles in organic media, subsequently coated with a poly(ethylene glycol) gallic acid polymer and phase transferred to water (SC-SPIONs). Our aim was to obtain long-term stable particles in aqueous media with high MPI performance. We found that the amplitude of the third harmonic measured by magnetic particle spectroscopy (MPS) at 10 mT is 2.3- and 5.8-fold higher than Resovist for the MC-SPIONs and SC-SPIONs, respectively, revealing excellent MPI potential as compared to other reported MPI tracer particle preparations. We show that the reconstructed MPI images of phantoms using optimized multicore and specifically single-core particles are superior to that of commercially available Resovist, which we utilize as a reference standard, as predicted by MPS.
Collapse
|
24
|
Shen Y, Gee MY, Greytak AB. Purification technologies for colloidal nanocrystals. Chem Commun (Camb) 2018; 53:827-841. [PMID: 27942615 DOI: 10.1039/c6cc07998a] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Almost all applications of colloidal nanocrystals require some type of purification or surface modification process following nanocrystal growth. Nanocrystal purification - the separation of nanocrystals from undesired solution components - can perturb the surface chemistry and thereby the physical properties of colloidal nanocrystals due to changes in solvent, solute concentrations, and exposure of the nanocrystal surface to oxidation or hydrolysis. For example, nanocrystal quantum dots frequently exhibit decreased photoluminescence brightness after precipitation from the growth solvent and subsequent redissolution. Consequently, purification is an integral part of the synthetic chemistry of colloidal nanocrystals, and the effect of purification methods must be considered in order to accurately compare and predict the behavior of otherwise similar nanocrystal samples. In this Feature Article we examine established and emerging approaches to the purification of colloidal nanoparticles from a nanocrystal surface chemistry viewpoint. Purification is generally achieved by exploiting differences in properties between the impurities and the nanoparticles. Three distinct properties are typically manipulated: polarity (relative solubility), electrophoretic mobility, and size. We discuss precipitation, extraction, electrophoretic methods, and size-based methods including ultracentrifugation, ultrafiltration, diafiltration, and size-exclusion chromatography. The susceptibility of quantum dots to changes in surface chemistry, with changes in photoluminescence decay associated with surface chemical changes, extends even into the case of core/shell structures. Accordingly, the goal of a more complete description of quantum dot surface chemistry has been a driver of innovation in colloidal nanocrystal purification methods. We specifically examine the effect of purification on surface chemistry and photoluminescence in quantum dots as an example of the challenges associated with nanocrystal purification and how improved understanding can result from increasingly precise techniques, and associated surface-sensitive analytical methods.
Collapse
Affiliation(s)
- Yi Shen
- Department of Chemistry and Biochemistry, University of South Carolina, Columbia, SC 29208, USA.
| | - Megan Y Gee
- Department of Chemistry and Biochemistry, University of South Carolina, Columbia, SC 29208, USA.
| | - A B Greytak
- Department of Chemistry and Biochemistry, University of South Carolina, Columbia, SC 29208, USA. and USC Nanocenter, University of South Carolina, Columbia, SC 29208, USA
| |
Collapse
|
25
|
The effect of post-synthesis aging on the ligand exchange activity of iron oxide nanoparticles. J Colloid Interface Sci 2018; 511:374-382. [DOI: 10.1016/j.jcis.2017.09.087] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2017] [Revised: 09/21/2017] [Accepted: 09/22/2017] [Indexed: 11/22/2022]
|
26
|
Kertmen A, Torruella P, Coy E, Yate L, Nowaczyk G, Gapiński J, Vogt C, Toprak M, Estradé S, Peiró F, Milewski S, Jurga S, Andruszkiewicz R. Acetate-Induced Disassembly of Spherical Iron Oxide Nanoparticle Clusters into Monodispersed Core-Shell Structures upon Nanoemulsion Fusion. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2017; 33:10351-10365. [PMID: 28895402 PMCID: PMC5730226 DOI: 10.1021/acs.langmuir.7b02743] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/05/2017] [Revised: 09/11/2017] [Indexed: 05/21/2023]
Abstract
It has been long known that the physical encapsulation of oleic acid-capped iron oxide nanoparticles (OA-IONPs) with the cetyltrimethylammonium (CTA+) surfactant induces the formation of spherical iron oxide nanoparticle clusters (IONPCs). However, the behavior and functional properties of IONPCs in chemical reactions have been largely neglected and are still not well-understood. Herein, we report an unconventional ligand-exchange function of IONPCs activated when dispersed in an ethyl acetate/acetate buffer system. The ligand exchange can successfully transform hydrophobic OA-IONP building blocks of IONPCs into highly hydrophilic, acetate-capped iron oxide nanoparticles (Ac-IONPs). More importantly, we demonstrate that the addition of silica precursors (tetraethyl orthosilicate and 3-aminopropyltriethoxysilane) to the acetate/oleate ligand-exchange reaction of the IONPs induces the disassembly of the IONPCs into monodispersed iron oxide-acetate-silica core-shell-shell (IONPs@acetate@SiO2) nanoparticles. Our observations evidence that the formation of IONPs@acetate@SiO2 nanoparticles is initiated by a unique micellar fusion mechanism between the Pickering-type emulsions of IONPCs and nanoemulsions of silica precursors formed under ethyl acetate buffered conditions. A dynamic rearrangement of the CTA+-oleate bilayer on the IONPC surfaces is proposed to be responsible for the templating process of the silica shells around the individual IONPs. In comparison to previously reported methods in the literature, our work provides a much more detailed experimental evidence of the silica-coating mechanism in a nanoemulsion system. Overall, ethyl acetate is proven to be a very efficient agent for an effortless preparation of monodispersed IONPs@acetate@SiO2 and hydrophilic Ac-IONPs from IONPCs.
Collapse
Affiliation(s)
- Ahmet Kertmen
- Department
of Pharmaceutical Technology and Biochemistry, Gdansk University of Technology, G. Narutowicza 11/12, 80-233 Gdansk, Poland
- NanoBioMedical
Centre, Adam Mickiewicz University, Umultowska 85, 61-614 Poznan, Poland
- Department
of Applied Physics, KTH-Royal Institute
of Technology, Roslagstullsbacken
21, SE-106 91 Stockholm, Sweden
| | - Pau Torruella
- LENS-MIND-IN2UB,
Departament d’Electronica, Universitat
de Barcelona, Martí i Franquès 1, 08028 Barcelona, Spain
| | - Emerson Coy
- NanoBioMedical
Centre, Adam Mickiewicz University, Umultowska 85, 61-614 Poznan, Poland
| | - Luis Yate
- CIC
biomaGUNE, Paseo Miramón 182, 20009 Donostia—San Sebastian, Spain
| | - Grzegorz Nowaczyk
- NanoBioMedical
Centre, Adam Mickiewicz University, Umultowska 85, 61-614 Poznan, Poland
| | - Jacek Gapiński
- NanoBioMedical
Centre, Adam Mickiewicz University, Umultowska 85, 61-614 Poznan, Poland
| | - Carmen Vogt
- Department
of Applied Physics, KTH-Royal Institute
of Technology, Roslagstullsbacken
21, SE-106 91 Stockholm, Sweden
| | - Muhammet Toprak
- Department
of Applied Physics, KTH-Royal Institute
of Technology, Roslagstullsbacken
21, SE-106 91 Stockholm, Sweden
| | - Sonia Estradé
- LENS-MIND-IN2UB,
Departament d’Electronica, Universitat
de Barcelona, Martí i Franquès 1, 08028 Barcelona, Spain
| | - Francesca Peiró
- LENS-MIND-IN2UB,
Departament d’Electronica, Universitat
de Barcelona, Martí i Franquès 1, 08028 Barcelona, Spain
| | - Sławomir Milewski
- Department
of Pharmaceutical Technology and Biochemistry, Gdansk University of Technology, G. Narutowicza 11/12, 80-233 Gdansk, Poland
| | - Stefan Jurga
- NanoBioMedical
Centre, Adam Mickiewicz University, Umultowska 85, 61-614 Poznan, Poland
| | - Ryszard Andruszkiewicz
- Department
of Pharmaceutical Technology and Biochemistry, Gdansk University of Technology, G. Narutowicza 11/12, 80-233 Gdansk, Poland
| |
Collapse
|
27
|
Jishkariani D, Lee JD, Yun H, Paik T, Kikkawa JM, Kagan CR, Donnio B, Murray CB. The dendritic effect and magnetic permeability in dendron coated nickel and manganese zinc ferrite nanoparticles. NANOSCALE 2017; 9:13922-13928. [PMID: 28905962 DOI: 10.1039/c7nr05769e] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
The collective magnetic properties of nanoparticle (NP) solid films are greatly affected by inter-particle dipole-dipole interactions and therefore the proximity of the neighboring particles. In this study, a series of dendritic ligands (generations 0 to 3, G0-G3) have been designed and used to cover the surface of magnetic NPs to control the spacings between the NP components in single lattices. The dendrons of different generations introduced here were based on the 2,2-bis(hydroxymethyl)propionic acid (Bis-MPA) scaffold and equipped with an appropriate surface binding group at one end and several fatty acid segments at the other extremity. The surface of the NPs was then modified by partial ligand exchange between the primary stabilizing surfactants and the new dendritic wedges. It was shown that this strategy permitted very precise tuning of inter-particle spacings in the range of 2.9-5.0 nm. As expected, the increase in the inter-particle spacings reduced the dipole-dipole interactions between magnetic NPs and therefore allowed changes in their magnetic permeability. The dendron size and inter-particle distance dependence was studied to reveal the dendritic effect and identify the optimal geometry and generation.
Collapse
Affiliation(s)
- Davit Jishkariani
- Department of Chemistry, University of Pennsylvania, Philadelphia, PA 19104, USA.
| | | | | | | | | | | | | | | |
Collapse
|
28
|
Jishkariani D, Wu Y, Wang D, Liu Y, van Blaaderen A, Murray CB. Preparation and Self-Assembly of Dendronized Janus Fe 3O 4-Pt and Fe 3O 4-Au Heterodimers. ACS NANO 2017; 11:7958-7966. [PMID: 28771319 DOI: 10.1021/acsnano.7b02485] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/14/2023]
Abstract
Janus nanoparticles (NPs) often referred to as nanosized analogs of molecular surfactants are amphiphilic structures with potential applications in materials science, biomedicine, and catalysis, and their synthesis and self-assembly into complex architectures remain challenging. Here, we demonstrate the preparation of Janus heterodimers via asymmetric functionalization of Fe3O4-Pt and Fe3O4-Au heterodimeric NPs. The hydrophobic and hydrophilic dendritic ligands that carry phosphonic acid and disulfide surface binding groups selectively coat the iron oxide and platinum (or gold) parts of the heterodimer, respectively. Such an approach allows simple and efficient preparation of amphiphilic structures. Moreover, liquid-air interface self-assembly studies of each ligand exchange step revealed a drastic improvement in film crystallinity, suggesting the dendronization induced improvement of the whole particle polydispersity of the heterodimers.
Collapse
Affiliation(s)
- Davit Jishkariani
- Complex Assemblies of Soft Matter Laboratory (COMPASS), UMI 3254, CNRS-Solvay-University of Pennsylvania , CRTB, 350 George Patterson Boulevard, Bristol, Pennsylvania 19007, United States
| | | | - Da Wang
- Soft Condensed Matter, Debye Institute for Nanomaterials Science, Utrecht University , Princetonplein 5, 3584 CC Utrecht, The Netherlands
| | - Yang Liu
- Soft Condensed Matter, Debye Institute for Nanomaterials Science, Utrecht University , Princetonplein 5, 3584 CC Utrecht, The Netherlands
- Department of Earth Sciences, Utrecht University , Budapestlaan 4, 3584 CD Utrecht, The Netherlands
| | - Alfons van Blaaderen
- Soft Condensed Matter, Debye Institute for Nanomaterials Science, Utrecht University , Princetonplein 5, 3584 CC Utrecht, The Netherlands
| | | |
Collapse
|
29
|
Photocatalytic study and superparamagnetic nature of Zn-doped MgFe 2 O 4 colloidal size nanocrystals prepared by solvothermal reflux method. JOURNAL OF PHOTOCHEMISTRY AND PHOTOBIOLOGY B-BIOLOGY 2017; 173:456-465. [DOI: 10.1016/j.jphotobiol.2017.06.025] [Citation(s) in RCA: 40] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/03/2017] [Revised: 06/16/2017] [Accepted: 06/21/2017] [Indexed: 01/20/2023]
|
30
|
Korpany KV, Majewski DD, Chiu CT, Cross SN, Blum AS. Iron Oxide Surface Chemistry: Effect of Chemical Structure on Binding in Benzoic Acid and Catechol Derivatives. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2017; 33:3000-3013. [PMID: 28215075 DOI: 10.1021/acs.langmuir.6b03491] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
The excellent performance of functionalized iron oxide nanoparticles (IONPs) in nanomaterial and biomedical applications often relies on achieving the attachment of ligands to the iron oxide surface both in sufficient number and with proper orientation. Toward this end, we determine relationships between the ligand chemical structure and surface binding on magnetic IONPs for a series of related benzoic acid and catechol derivatives. Ligand exchange was used to introduce the model ligands, and the resultant nanoparticles were characterized using Fourier transform infrared-attenuated internal reflectance spectroscopy, transmission electron microscopy, and nanoparticle solubility behavior. An in-depth analysis of ligand electronic effects and reaction conditions reveals that the nature of ligand binding does not solely depend on the presence of functional groups known to bind to IONPs. The structure of the resultant ligand-surface complex was primarily influenced by the relative positioning of hydroxyl and carboxylic acid groups within the ligand and whether or not HCl(aq) was added to the ligand-exchange reaction. Overall, this study will help guide future ligand-design and ligand-exchange strategies toward realizing truly custom-built IONPs.
Collapse
Affiliation(s)
- Katalin V Korpany
- Department of Chemistry, McGill University , 801 Sherbrooke Street West, Montreal, Quebec H3A 0B8, Canada
| | - Dorothy D Majewski
- Department of Chemistry, McGill University , 801 Sherbrooke Street West, Montreal, Quebec H3A 0B8, Canada
| | - Cindy T Chiu
- Department of Chemistry, McGill University , 801 Sherbrooke Street West, Montreal, Quebec H3A 0B8, Canada
| | - Shoronia N Cross
- Department of Chemistry, McGill University , 801 Sherbrooke Street West, Montreal, Quebec H3A 0B8, Canada
| | - Amy Szuchmacher Blum
- Department of Chemistry, McGill University , 801 Sherbrooke Street West, Montreal, Quebec H3A 0B8, Canada
| |
Collapse
|
31
|
Davis K, Cole B, Ghelardini M, Powell BA, Mefford OT. Quantitative Measurement of Ligand Exchange with Small-Molecule Ligands on Iron Oxide Nanoparticles via Radioanalytical Techniques. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2016; 32:13716-13727. [PMID: 27966977 DOI: 10.1021/acs.langmuir.6b03644] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
Ligand exchange on the surface of hydrophobic iron oxide nanoparticles is a common method for controlling surface chemistry for a desired application. Furthermore, ligand exchange with small-molecule ligands may be necessary to obtain particles with a specific size or functionality. Understanding to what extent ligand exchange occurs and what factors affect it is important for the optimization of this critical procedure. However, quantifying the amount of exchange may be difficult because of the limitations of commonly used characterization techniques. Therefore, we utilized a radiotracer technique to track the exchange of a radiolabeled 14C-oleic acid ligand with hydrophilic small-molecule ligands on the surface of iron oxide nanoparticles. Iron oxide nanoparticles functionalized with 14C-oleic acid were modified with small-molecule ligands with terminal functional groups including catechols, phosphonates, sulfonates, thiols, carboxylic acids, and silanes. These moieties were selected because they represent the most commonly used ligands for this procedure. The effectiveness of these molecules was compared using both procedures widely found in the literature and using a standardized procedure. After ligand exchange, the nanoparticles were analyzed using liquid scintillation counting (LSC) and inductively coupled plasma-mass spectrometry. The labeled and unlabeled particles were further characterized by transmission electron microscopy (TEM) and dynamic light scattering (DLS) to determine the particle size, hydrodynamic diameter, and zeta potential. The unlabeled particles were characterized via attenuated total reflectance-Fourier transform infrared spectroscopy (ATR-FTIR) and vibrating sample magnetometry (VSM) to confirm the presence of the small molecules on the particles and verify the magnetic properties, respectively. Radioanalytical determination of 14C-oleic acid was used to calculate the total amount of oleic acid remaining on the surface of the particles after ligand exchange. The results revealed that the ligand-exchange reactions performed using widely cited procedures did not go to completion. Residual oleic acid remained on the particles after these reactions and the reactions using a standardized protocol. A comparison of the ligand-exchange procedures indicated that the binding moiety, multidenticity, reaction time, temperature, and presence of a catalyst impacted the extent of exchange. Quantification of the oleic acid remaining after ligand exchange revealed a binding hierarchy in which catechol-derived anchor groups displace the most oleic acid on the surface of the nanoparticles and the thiol group displaces the least amount of oleic acid. Thorough characterization of ligand exchange is required to develop nanoparticles suitable for their intended application.
Collapse
Affiliation(s)
| | - Brian Cole
- Department of Chemistry, Henderson State University , Arkadelphia, Arkansas 71999, United States
| | | | | | | |
Collapse
|
32
|
Majeed MI, Guo J, Yan W, Tan B. Preparation of Magnetic Iron Oxide Nanoparticles (MIONs) with Improved Saturation Magnetization Using Multifunctional Polymer Ligand. Polymers (Basel) 2016; 8:E392. [PMID: 30974667 PMCID: PMC6432320 DOI: 10.3390/polym8110392] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2016] [Revised: 10/30/2016] [Accepted: 10/31/2016] [Indexed: 12/19/2022] Open
Abstract
This paper describes the preparation of ultra-small magnetic iron oxide (Fe₃O₄) nanoparticles (MIONs) coated with water-soluble thioether end-functionalized polymer ligand pentaerythritol tetrakis 3-mercaptopropionate-polymethacrylic acid (PTMP-PMAA). The MIONs were prepared by co-precipitation of aqueous iron precursor solution at a high temperature. The polymer modified MIONs were characterized by dynamic light scattering (DLS), transmission electron microscopy (TEM), Fourier transform infrared spectroscopy (FTIR), X-ray powder diffraction (XRD), thermogravimetric analysis (TGA), and vibrating sample magnetometery (VSM). It was found that these MIONs were successfully modified by this water-soluble polymer ligand with a fairly uniform size and narrow size distribution. The dried powder of MIONs could be stored for a long time and re-dispersed well in water without any significant change. Additionally, the polymer concentration showed a significant effect on size and magnetic properties of the MIONs. The saturation magnetization was increased by optimizing the polymer concentration. Furthermore, the 3-(4,5-dimethylthiazol-2-yl)-2-5-diphenyltetrazolium bromide (MTT)-assay demonstrated that these MIONs were highly biocompatible and they could be successfully coupled with fluorescent dye Rhodamine due to the formation of amide bond between carboxylic acid groups of MIONs and amine groups of dye. The obtained results indicated that these multifunctional MIONs with rich surface chemistry exhibit admirable potential in biomedical applications.
Collapse
Affiliation(s)
- Muhammad Irfan Majeed
- School of Chemistry and Chemical Engineering, Huazhong University of Science and Technology, Wuhan 430074, China.
| | - Jiaojiao Guo
- School of Chemistry and Chemical Engineering, Huazhong University of Science and Technology, Wuhan 430074, China.
- Hubei Collaborative Innovation Center for Advanced Organic Chemical Materials, Ministry of Education, Key Laboratory of Green Preparation and Application for Functional Materials, Hubei Key Laboratory of Polymer Materials, School of Materials Science & Engineering, Hubei University, Wuhan 430062, China.
| | - Wei Yan
- School of Chemistry and Chemical Engineering, Huazhong University of Science and Technology, Wuhan 430074, China.
- Hubei Collaborative Innovation Center for Advanced Organic Chemical Materials, Ministry of Education, Key Laboratory of Green Preparation and Application for Functional Materials, Hubei Key Laboratory of Polymer Materials, School of Materials Science & Engineering, Hubei University, Wuhan 430062, China.
| | - Bien Tan
- School of Chemistry and Chemical Engineering, Huazhong University of Science and Technology, Wuhan 430074, China.
| |
Collapse
|
33
|
Shen Y, Roberge A, Tan R, Gee MY, Gary DC, Huang Y, Blom DA, Benicewicz BC, Cossairt BM, Greytak AB. Gel permeation chromatography as a multifunctional processor for nanocrystal purification and on-column ligand exchange chemistry. Chem Sci 2016; 7:5671-5679. [PMID: 30034705 PMCID: PMC6022040 DOI: 10.1039/c6sc01301e] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2016] [Accepted: 05/20/2016] [Indexed: 01/31/2023] Open
Abstract
This article illustrates the use of gel permeation chromatography (GPC, organic-phase size exclusion chromatography) to separate nanocrystals from weakly-bound small molecules, including solvent, on the basis of size. A variety of colloidal inorganic nanocrystals of different size, shape, composition, and surface termination are shown to yield purified samples with greatly reduced impurity concentrations. Additionally, the method is shown to be useful in achieving a change of solvent without requiring precipitation of the nanocrystals. By taking advantage of the different rates at which small molecules and nanoparticles travel through the column, we show that it is furthermore possible to use the GPC column as a multi-functional flow reactor that can accomplish in sequence the steps of initial purification, ligand exchange with controlled reactant concentration and interaction time, and subsequent cleanup without requiring a change of phase. This example of process intensification via GPC is shown to yield nearly complete displacement of the initial surface ligand population upon reaction with small molecule and macromolecular reactants to form ligand-exchanged nanocrystal products.
Collapse
Affiliation(s)
- Yi Shen
- Department of Chemistry and Biochemistry , University of South Carolina , Columbia , SC 29208 , USA .
| | - Adam Roberge
- Department of Chemistry and Biochemistry , University of South Carolina , Columbia , SC 29208 , USA .
| | - Rui Tan
- Department of Chemistry and Biochemistry , University of South Carolina , Columbia , SC 29208 , USA .
| | - Megan Y Gee
- Department of Chemistry and Biochemistry , University of South Carolina , Columbia , SC 29208 , USA .
| | - Dylan C Gary
- Department of Chemistry , University of Washington , Seattle , WA 98195 , USA
| | - Yucheng Huang
- Department of Chemistry and Biochemistry , University of South Carolina , Columbia , SC 29208 , USA .
| | - Douglas A Blom
- USC Nanocenter , University of South Carolina , Columbia , SC 29208 , USA
| | - Brian C Benicewicz
- Department of Chemistry and Biochemistry , University of South Carolina , Columbia , SC 29208 , USA .
- USC Nanocenter , University of South Carolina , Columbia , SC 29208 , USA
| | - Brandi M Cossairt
- Department of Chemistry , University of Washington , Seattle , WA 98195 , USA
| | - Andrew B Greytak
- Department of Chemistry and Biochemistry , University of South Carolina , Columbia , SC 29208 , USA .
- USC Nanocenter , University of South Carolina , Columbia , SC 29208 , USA
| |
Collapse
|
34
|
Lam T, Avti PK, Pouliot P, Maafi F, Tardif JC, Rhéaume É, Lesage F, Kakkar A. Fabricating Water Dispersible Superparamagnetic Iron Oxide Nanoparticles for Biomedical Applications through Ligand Exchange and Direct Conjugation. NANOMATERIALS (BASEL, SWITZERLAND) 2016; 6:E100. [PMID: 28335228 PMCID: PMC5302624 DOI: 10.3390/nano6060100] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/13/2016] [Revised: 04/29/2016] [Accepted: 05/13/2016] [Indexed: 12/20/2022]
Abstract
Stable superparamagnetic iron oxide nanoparticles (SPIONs), which can be easily dispersed in an aqueous medium and exhibit high magnetic relaxivities, are ideal candidates for biomedical applications including contrast agents for magnetic resonance imaging. We describe a versatile methodology to render water dispersibility to SPIONs using tetraethylene glycol (TEG)-based phosphonate ligands, which are easily introduced onto SPIONs by either a ligand exchange process of surface-anchored oleic-acid (OA) molecules or via direct conjugation. Both protocols confer good colloidal stability to SPIONs at different NaCl concentrations. A detailed characterization of functionalized SPIONs suggests that the ligand exchange method leads to nanoparticles with better magnetic properties but higher toxicity and cell death, than the direct conjugation methodology.
Collapse
Affiliation(s)
- Tina Lam
- Department of Chemistry, McGill University, 801 Sherbrooke Street West, Montreal, QC H3A 0B8, Canada.
| | - Pramod K Avti
- Department of Chemistry, McGill University, 801 Sherbrooke Street West, Montreal, QC H3A 0B8, Canada.
- Department of Electrical Engineering, École Polytechnique de Montréal, C.P. 6079 succ. Centre-ville, Montreal, QC H3C 3A7, Canada.
- Research Center, Montreal Heart Institute, 5000 Bélanger Street, Montreal, QC H1T 1C8, Canada.
| | - Philippe Pouliot
- Department of Electrical Engineering, École Polytechnique de Montréal, C.P. 6079 succ. Centre-ville, Montreal, QC H3C 3A7, Canada.
- Research Center, Montreal Heart Institute, 5000 Bélanger Street, Montreal, QC H1T 1C8, Canada.
| | - Foued Maafi
- Research Center, Montreal Heart Institute, 5000 Bélanger Street, Montreal, QC H1T 1C8, Canada.
| | - Jean-Claude Tardif
- Research Center, Montreal Heart Institute, 5000 Bélanger Street, Montreal, QC H1T 1C8, Canada.
- Department of Medicine, Université de Montréal, Montreal, QC H3T 1J4, Canada.
| | - Éric Rhéaume
- Research Center, Montreal Heart Institute, 5000 Bélanger Street, Montreal, QC H1T 1C8, Canada.
- Department of Medicine, Université de Montréal, Montreal, QC H3T 1J4, Canada.
| | - Frédéric Lesage
- Department of Electrical Engineering, École Polytechnique de Montréal, C.P. 6079 succ. Centre-ville, Montreal, QC H3C 3A7, Canada.
- Research Center, Montreal Heart Institute, 5000 Bélanger Street, Montreal, QC H1T 1C8, Canada.
| | - Ashok Kakkar
- Department of Chemistry, McGill University, 801 Sherbrooke Street West, Montreal, QC H3A 0B8, Canada.
| |
Collapse
|
35
|
Lassenberger A, Bixner O, Gruenewald T, Lichtenegger H, Zirbs R, Reimhult E. Evaluation of High-Yield Purification Methods on Monodisperse PEG-Grafted Iron Oxide Nanoparticles. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2016; 32:4259-69. [PMID: 27046133 PMCID: PMC4868375 DOI: 10.1021/acs.langmuir.6b00919] [Citation(s) in RCA: 36] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/08/2016] [Revised: 04/05/2016] [Indexed: 05/24/2023]
Abstract
Fundamental research on nanoparticle (NP) interactions and development of next-generation biomedical NP applications relies on synthesis of monodisperse, functional, core-shell nanoparticles free of residual dispersants with truly homogeneous and controlled physical properties. Still, synthesis and purification of e.g. such superparamagnetic iron oxide NPs remain a challenge. Comparing the success of different methods is marred by the sensitivity of analysis methods to the purity of the product. We synthesize monodisperse, oleic acid (OA)-capped, Fe3O4 NPs in the superparamagnetic size range (3-10 nm). Ligand exchange of OA for poly(ethylene glycol) (PEG) was performed with the PEG irreversibly grafted to the NP surface by a nitrodopamine (NDA) anchor. Four different methods were investigated to remove excess ligands and residual OA: membrane centrifugation, dialysis, size exclusion chromatography, and precipitation combined with magnetic decantation. Infrared spectroscopy and thermogravimetric analysis were used to determine the purity of samples after each purification step. Importantly, only magnetic decantation yielded pure NPs at high yields with sufficient grafting density for biomedical applications (∼1 NDA-PEG(5 kDa)/nm(2), irrespective of size). The purified NPs withstand challenging tests such as temperature cycling in serum and long-term storage in biological buffers. Dynamic light scattering, transmission electron microscopy, and small-angle X-ray scattering show stability over at least 4 months also in serum. The successful synthesis and purification route is compatible with any conceivable functionalization for biomedical or biomaterial applications of PEGylated Fe3O4 NPs.
Collapse
Affiliation(s)
- Andrea Lassenberger
- Department
of Nanobiotechnology, Institute for Biologically Inspired Materials, University of Natural Resources and Life Sciences, Muthgasse 11, 1190 Vienna, Austria
| | - Oliver Bixner
- Department
of Nanobiotechnology, Institute for Biologically Inspired Materials, University of Natural Resources and Life Sciences, Muthgasse 11, 1190 Vienna, Austria
| | - Tilman Gruenewald
- Department
of Material Science and Process Engineering, Institute of Physics and Materials Science, Peter-Jordan Strasse 82, 1190 Vienna, Austria
| | - Helga Lichtenegger
- Department
of Material Science and Process Engineering, Institute of Physics and Materials Science, Peter-Jordan Strasse 82, 1190 Vienna, Austria
| | - Ronald Zirbs
- Department
of Nanobiotechnology, Institute for Biologically Inspired Materials, University of Natural Resources and Life Sciences, Muthgasse 11, 1190 Vienna, Austria
| | - Erik Reimhult
- Department
of Nanobiotechnology, Institute for Biologically Inspired Materials, University of Natural Resources and Life Sciences, Muthgasse 11, 1190 Vienna, Austria
| |
Collapse
|
36
|
Hore MJA, Ye X, Ford J, Gao Y, Fei J, Wu Q, Rowan SJ, Composto RJ, Murray CB, Hammouda B. Probing the Structure, Composition, and Spatial Distribution of Ligands on Gold Nanorods. NANO LETTERS 2015; 15:5730-5738. [PMID: 26292087 DOI: 10.1021/acs.nanolett.5b03088] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
The structure and size of ligands attached to the surfaces of gold nanorods, such as adsorbed surfactants or grafted polymers, are important considerations that facilitate the use of such nanoparticles in the human body, in advanced materials for energy harvesting, or in devices for single molecule detection. Here, we report small-angle neutron scattering (SANS) measurements from surfactant or poly(ethylene glycol) (PEG) coated gold nanorods in solution, which quantitatively determine the location, structure, and composition of these surface layers. In addition, by synthesizing gold nanorods using seed crystals which are coated with deuterated cetyltrimethylammonium bromide (dCTAB), we are able to exploit the isotopic sensitivity of SANS to study, for the first time, the retention of surfactant from the seed crystals to the final gold nanorod product, finding that very little exchange of the deuterated with hydrogenated surfactant occurs. Finally, we demonstrate that, when Au NRs are PEGylated using standard techniques, the surfactant bilayer remains intact, and while mass spectrometry detects the presence of both surfactant and PEG, the composition as measured from SANS is predominantly that of the surfactant. These measurements not only provide new insight into the synthesis and functionalization of gold nanorods but provide a quantitative picture of the structure of grafted polymer and surfactant layers on gold nanorod surfaces which has implications for the fabrication of plasmonic and biomedical materials.
Collapse
Affiliation(s)
- Michael J A Hore
- National Institute of Standards and Technology , Center for Neutron Research, 100 Bureau Drive, Gaithersburg, Maryland 20899, United States
- Department of Macromolecular Science & Engineering, Case Western Reserve University , 10900 Euclid Avenue, Cleveland, Ohio 44106, United States
| | | | | | | | | | - Qiong Wu
- Department of Macromolecular Science & Engineering, Case Western Reserve University , 10900 Euclid Avenue, Cleveland, Ohio 44106, United States
| | - Stuart J Rowan
- Department of Macromolecular Science & Engineering, Case Western Reserve University , 10900 Euclid Avenue, Cleveland, Ohio 44106, United States
| | | | | | - Boualem Hammouda
- National Institute of Standards and Technology , Center for Neutron Research, 100 Bureau Drive, Gaithersburg, Maryland 20899, United States
| |
Collapse
|
37
|
Kurzhals S, Zirbs R, Reimhult E. Synthesis and Magneto-Thermal Actuation of Iron Oxide Core-PNIPAM Shell Nanoparticles. ACS APPLIED MATERIALS & INTERFACES 2015; 7:19342-52. [PMID: 26270412 PMCID: PMC4559841 DOI: 10.1021/acsami.5b05459] [Citation(s) in RCA: 43] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/19/2015] [Accepted: 08/13/2015] [Indexed: 05/03/2023]
Abstract
Superparamagnetic nanoparticles have been proposed for many applications in biotechnology and medicine. In this paper, it is demonstrated how the excellent colloidal stability and magnetic properties of monodisperse and individually densely grafted iron oxide nanoparticles can be used to manipulate reversibly the solubility of nanoparticles with a poly(N-isopropylacrylamide)nitrodopamine shell. "Grafting-to" and "grafting-from" methods for synthesis of an irreversibly anchored brush shell to monodisperse, oleic acid coated iron oxide cores are compared. Thereafter, it is shown that local heating by magnetic fields as well as global thermal heating can be used to efficiently and reversibly aggregate, magnetically extract nanoparticles from solution and spontaneously redisperse them. The coupling of magnetic and thermally responsive properties points to novel uses as smart materials, for example, in integrated devices for molecular separation and extraction.
Collapse
Affiliation(s)
- Steffen Kurzhals
- Institute for Biologically Inspired Materials, Department of Nanobiotechnology, University
of Natural Resources and Life Sciences, Vienna, Muthgasse 11, A-1190 Vienna, Austria
| | - Ronald Zirbs
- Institute for Biologically Inspired Materials, Department of Nanobiotechnology, University
of Natural Resources and Life Sciences, Vienna, Muthgasse 11, A-1190 Vienna, Austria
| | - Erik Reimhult
- Institute for Biologically Inspired Materials, Department of Nanobiotechnology, University
of Natural Resources and Life Sciences, Vienna, Muthgasse 11, A-1190 Vienna, Austria
| |
Collapse
|
38
|
Bixner O, Lassenberger A, Baurecht D, Reimhult E. Complete Exchange of the Hydrophobic Dispersant Shell on Monodisperse Superparamagnetic Iron Oxide Nanoparticles. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2015; 31:9198-9204. [PMID: 26226071 PMCID: PMC4554299 DOI: 10.1021/acs.langmuir.5b01833] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/19/2015] [Revised: 07/30/2015] [Indexed: 05/19/2023]
Abstract
High-temperature synthesized monodisperse superparamagnetic iron oxide nanoparticles are obtained with a strongly bound ligand shell of oleic acid and its decomposition products. Most applications require a stable presentation of a defined surface chemistry; therefore, the native shell has to be completely exchanged for dispersants with irreversible affinity to the nanoparticle surface. We evaluate by attenuated total reflectance-Fourier transform infrared spectroscopy (ATR-FTIR) and thermogravimetric analysis/differential scanning calorimetry (TGA/DSC) the limitations of commonly used approaches. A mechanism and multiple exchange scheme that attains the goal of complete and irreversible ligand replacement on monodisperse nanoparticles of various sizes is presented. The obtained hydrophobic nanoparticles are ideally suited for magnetically controlled drug delivery and membrane applications and for the investigation of fundamental interfacial properties of ultrasmall core-shell architectures.
Collapse
Affiliation(s)
- Oliver Bixner
- Department
of Nanobiotechnology, Institute for Biologically Inspired Materials, University of Natural Resources and Life Sciences
Vienna, Muthgasse 11, 1190 Vienna, Austria
- School
of Materials Science and Engineering, Centre for Biomimetic Sensor
Science, Nanyang Technological University, 50 Nanyang Drive, Singapore 637553, Singapore
| | - Andrea Lassenberger
- Department
of Nanobiotechnology, Institute for Biologically Inspired Materials, University of Natural Resources and Life Sciences
Vienna, Muthgasse 11, 1190 Vienna, Austria
| | - Dieter Baurecht
- Faculty
of Chemistry, Department of Physical Chemistry, University of Vienna, Währingerstraße 42, 1090 Vienna, Austria
| | - Erik Reimhult
- Department
of Nanobiotechnology, Institute for Biologically Inspired Materials, University of Natural Resources and Life Sciences
Vienna, Muthgasse 11, 1190 Vienna, Austria
- E-mail:
| |
Collapse
|
39
|
Grünewald TA, Lassenberger A, van
Oostrum PDJ, Rennhofer H, Zirbs R, Capone B, Vonderhaid I, Amenitsch H, Lichtenegger HC, Reimhult E. Core-Shell Structure of Monodisperse Poly(ethylene glycol)-Grafted Iron Oxide Nanoparticles Studied by Small-Angle X-ray Scattering. CHEMISTRY OF MATERIALS : A PUBLICATION OF THE AMERICAN CHEMICAL SOCIETY 2015; 27:4763-4771. [PMID: 26321792 PMCID: PMC4547501 DOI: 10.1021/acs.chemmater.5b01488] [Citation(s) in RCA: 44] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/27/2015] [Revised: 06/17/2015] [Indexed: 05/04/2023]
Abstract
The promising applications of core-shell nanoparticles in the biological and medical field have been well investigated in recent years. One remaining challenge is the characterization of the structure of the hydrated polymer shell. Here we use small-angle X-ray scattering (SAXS) to investigate iron oxide core-poly(ethylene glycol) brush shell nanoparticles with extremely high polymer grafting density. It is shown that the shell density profile can be described by a scaling model that takes into account the locally very high grafting density near the core. A good fit to a constant density region followed by a star-polymer-like, monotonously decaying density profile is shown, which could help explain the unique colloidal properties of such densely grafted core-shell nanoparticles. SAXS experiments probing the thermally induced dehydration of the shell and the response to dilution confirmed that the observed features are associated with the brush and not attributed to structure factors from particle aggregates. We thereby demonstrate that the structure of monodisperse core-shell nanoparticles with dense solvated shells can be well studied with SAXS and that different density models can be distinguished from each other.
Collapse
Affiliation(s)
- Tilman A. Grünewald
- Department of Material
Sciences and Process Engineering, University
of Natural Resources and Life Sciences, Vienna, Peter-Jordan-Straße 82, A-1190 Vienna, Austria
| | - Andrea Lassenberger
- Department of Nanobiotechnology, University of Natural Resources and Life Sciences, Vienna, Muthgasse 11, A-1190 Vienna, Austria
| | - Peter D. J. van
Oostrum
- Department of Nanobiotechnology, University of Natural Resources and Life Sciences, Vienna, Muthgasse 11, A-1190 Vienna, Austria
| | - Harald Rennhofer
- Department of Material
Sciences and Process Engineering, University
of Natural Resources and Life Sciences, Vienna, Peter-Jordan-Straße 82, A-1190 Vienna, Austria
| | - Ronald Zirbs
- Department of Nanobiotechnology, University of Natural Resources and Life Sciences, Vienna, Muthgasse 11, A-1190 Vienna, Austria
| | - Barbara Capone
- Faculty of Physics, University of Vienna, Boltzmanngasse 5, A-1090 Vienna, Austria
| | - Iris Vonderhaid
- Department of Nanobiotechnology, University of Natural Resources and Life Sciences, Vienna, Muthgasse 11, A-1190 Vienna, Austria
| | - Heinz Amenitsch
- Institute for Inorganic Chemistry, Graz University of Technology, Stremayrgasse 9/V, A-8010 Graz, Austria
| | - Helga C. Lichtenegger
- Department of Material
Sciences and Process Engineering, University
of Natural Resources and Life Sciences, Vienna, Peter-Jordan-Straße 82, A-1190 Vienna, Austria
- E-mail:
| | - Erik Reimhult
- Department of Nanobiotechnology, University of Natural Resources and Life Sciences, Vienna, Muthgasse 11, A-1190 Vienna, Austria
- E-mail:
| |
Collapse
|
40
|
Raval YS, Stone R, Fellows B, Qi B, Huang G, Mefford OT, Tzeng TRJ. Synthesis and application of glycoconjugate-functionalized magnetic nanoparticles as potent anti-adhesion agents for reducing enterotoxigenic Escherichia coli infections. NANOSCALE 2015; 7:8326-8331. [PMID: 25896754 DOI: 10.1039/c5nr00511f] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
Polyethylene oxide stabilized magnetic nanoparticles (PEO-MNPs) bio-functionalized with glycoconjugate (Neu5Ac(α2-3)Gal(β1-4)Glcβ-sp) (GM3-MNPs) are synthesized using click chemistry. Interaction of GM3-MNPs with Enterotoxigenic Escherichia coli (ETEC) strain K99 (EC K99) is investigated using different microscopic techniques. Our results suggest that GM3-MNPs can effectively act as non-antibiotic anti-adhesion agents for treating ETEC infections.
Collapse
Affiliation(s)
- Yash S Raval
- Department of Biological Sciences, Clemson University, Clemson, SC 29634, USA.
| | | | | | | | | | | | | |
Collapse
|
41
|
Shen Y, Tan R, Gee MY, Greytak AB. Quantum yield regeneration: influence of neutral ligand binding on photophysical properties in colloidal core/shell quantum dots. ACS NANO 2015; 9:3345-59. [PMID: 25753127 DOI: 10.1021/acsnano.5b00671] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/21/2023]
Abstract
This article describes an experiment designed to identify the role of specific molecular ligands in maintaining the high photoluminescence (PL) quantum yield (QY) observed in as-synthesized CdSe/CdZnS and CdSe/CdS quantum dots (QDs). Although it has been possible for many years to prepare core/shell quantum dots with near-unity quantum yield through high-temperature colloidal synthesis, purification of such colloidal particles is frequently accompanied by a reduction in quantum yield. Here, a recently established gel permeation chromatography (GPC) technique is used to remove weakly associated ligands without a change in solvent: a decrease in ensemble QY and average PL lifetime is observed. Minor components of the initial mixture that were removed by GPC are then added separately to purified QD samples to determine whether reintroduction of these components can restore the photophysical properties of the initial sample. We show that among these putative ligands trioctylphosphine and cadmium oleate can regenerate the initial high QY of all samples, but only the "L-type" ligands (trioctyphosphine and oleylamine) can restore the QY without changing the shapes of the optical spectra. On the basis of the PL decay analysis, we confirm that quenching in GPC-purified samples and regeneration in ligand-introduced samples are associated chiefly with changes in the relative population fraction of QDs with different decay rates. The reversibility of the QY regeneration process has also been studied; the introduction and removal of trioctylphosphine and oleylamine tend to be reversible, while cadmium oleate is not. Finally, isothermal titration calorimetry has been used to study the relationship between the binding strength of the neutral ligands to the surface and photophysical property changes in QD samples to which they are added.
Collapse
Affiliation(s)
- Yi Shen
- †Department of Chemistry and Biochemistry and ‡USC Nanocenter, University of South Carolina, Columbia, South Carolina 29208, United States
| | - Rui Tan
- †Department of Chemistry and Biochemistry and ‡USC Nanocenter, University of South Carolina, Columbia, South Carolina 29208, United States
| | - Megan Y Gee
- †Department of Chemistry and Biochemistry and ‡USC Nanocenter, University of South Carolina, Columbia, South Carolina 29208, United States
| | - Andrew B Greytak
- †Department of Chemistry and Biochemistry and ‡USC Nanocenter, University of South Carolina, Columbia, South Carolina 29208, United States
| |
Collapse
|