1
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Delille F, Pu Y, Lequeux N, Pons T. Designing the Surface Chemistry of Inorganic Nanocrystals for Cancer Imaging and Therapy. Cancers (Basel) 2022; 14:2456. [PMID: 35626059 PMCID: PMC9139368 DOI: 10.3390/cancers14102456] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2022] [Revised: 05/10/2022] [Accepted: 05/12/2022] [Indexed: 12/27/2022] Open
Abstract
Inorganic nanocrystals, such as gold, iron oxide and semiconductor quantum dots, offer promising prospects for cancer diagnostics, imaging and therapy, due to their specific plasmonic, magnetic or fluorescent properties. The organic coating, or surface ligands, of these nanoparticles ensures their colloidal stability in complex biological fluids and enables their functionalization with targeting functions. It also controls the interactions of the nanoparticle with biomolecules in their environment. It therefore plays a crucial role in determining nanoparticle biodistribution and, ultimately, the imaging or therapeutic efficiency. This review summarizes the various strategies used to develop optimal surface chemistries for the in vivo preclinical and clinical application of inorganic nanocrystals. It discusses the current understanding of the influence of the nanoparticle surface chemistry on its colloidal stability, interaction with proteins, biodistribution and tumor uptake, and the requirements to develop an optimal surface chemistry.
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Affiliation(s)
- Fanny Delille
- Laboratoire de Physique et d’Etude des Matériaux, Ecole Supérieure de Physique et Chimie Industrielle, Université PSL (Paris Sciences & Lettres), Centre National de Recherche Scientifique, 75005 Paris, France; (F.D.); (Y.P.); (N.L.)
- Laboratoire de Physique et d’Etude des Matériaux, Centre National de Recherche Scientifique, Sorbonne Université, 75005 Paris, France
| | - Yuzhou Pu
- Laboratoire de Physique et d’Etude des Matériaux, Ecole Supérieure de Physique et Chimie Industrielle, Université PSL (Paris Sciences & Lettres), Centre National de Recherche Scientifique, 75005 Paris, France; (F.D.); (Y.P.); (N.L.)
- Laboratoire de Physique et d’Etude des Matériaux, Centre National de Recherche Scientifique, Sorbonne Université, 75005 Paris, France
| | - Nicolas Lequeux
- Laboratoire de Physique et d’Etude des Matériaux, Ecole Supérieure de Physique et Chimie Industrielle, Université PSL (Paris Sciences & Lettres), Centre National de Recherche Scientifique, 75005 Paris, France; (F.D.); (Y.P.); (N.L.)
- Laboratoire de Physique et d’Etude des Matériaux, Centre National de Recherche Scientifique, Sorbonne Université, 75005 Paris, France
| | - Thomas Pons
- Laboratoire de Physique et d’Etude des Matériaux, Ecole Supérieure de Physique et Chimie Industrielle, Université PSL (Paris Sciences & Lettres), Centre National de Recherche Scientifique, 75005 Paris, France; (F.D.); (Y.P.); (N.L.)
- Laboratoire de Physique et d’Etude des Matériaux, Centre National de Recherche Scientifique, Sorbonne Université, 75005 Paris, France
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2
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Willinger M, Reimhult E. Thermoresponsive Nanoparticles with Cyclic-Polymer-Grafted Shells Are More Stable than with Linear-Polymer-Grafted Shells: Effect of Polymer Topology, Molecular Weight, and Core Size. J Phys Chem B 2021; 125:7009-7023. [PMID: 34156854 PMCID: PMC8279546 DOI: 10.1021/acs.jpcb.1c00142] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2021] [Revised: 05/26/2021] [Indexed: 11/27/2022]
Abstract
Polymer brush-grafted superparamagnetic iron oxide nanoparticles can change their aggregation state in response to temperature and are potential smart materials for many applications. Recently, the shell morphology imposed by grafting to a nanoparticle core was shown to strongly influence the thermoresponsiveness through a coupling of intrashell solubility transitions and nanoparticle aggregation. We investigate how a change from linear to cyclic polymer topology affects the thermoresponsiveness of poly(2-isopropyl-2-oxazoline) brush-grafted superparamagnetic iron oxide nanoparticles. Linear and cyclic polymers with three different molecular weights (7, 18, and 24.5 kg mol-1) on two different core sizes (3.7 and 9.2 nm) and as free polymer were investigated. We observed the critical flocculation temperature (CFT) during temperature cycling dynamic light scattering experiments, the critical solution temperature (CST), and the transition enthalpy per monomer during differential scanning calorimetry measurements. When all conditions are identical, cyclic polymers increase the colloidal stability and the critical flocculation temperature compared to their linear counterparts. Furthermore, the cyclic polymer shows only one uniform transition, while we observe multiple transitions for the linear polymer shells. We link the single transition and higher colloidal stability to the absence in cyclic PiPrOx shells of a dilute outer part where the particle shells can interdigitate.
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Affiliation(s)
- Max Willinger
- Institute for Biologically Inspired
Materials, Department of Nanobiotechnology, University of Natural Resources and Life Sciences Vienna, Muthgasse 11, 1190 Vienna, Austria
| | - Erik Reimhult
- Institute for Biologically Inspired
Materials, Department of Nanobiotechnology, University of Natural Resources and Life Sciences Vienna, Muthgasse 11, 1190 Vienna, Austria
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3
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Liu D, Sun J. Thermoresponsive Polypeptoids. Polymers (Basel) 2020; 12:E2973. [PMID: 33322804 PMCID: PMC7763442 DOI: 10.3390/polym12122973] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2020] [Revised: 12/10/2020] [Accepted: 12/11/2020] [Indexed: 01/02/2023] Open
Abstract
Stimuli-responsive polymers have been widely studied in many applications such as biomedicine, nanotechnology, and catalysis. Temperature is one of the most commonly used external triggers, which can be highly controlled with excellent reversibility. Thermoresponsive polymers exhibiting a reversible phase transition in a controlled manner to temperature are a promising class of smart polymers that have been widely studied. The phase transition behavior can be tuned by polymer architectures, chain-end, and various functional groups. Particularly, thermoresponsive polypeptoid is a type of promising material that has drawn growing interest because of its excellent biocompatibility, biodegradability, and bioactivity. This paper summarizes the recent advances of thermoresponsive polypeptoids, including the synthetic methods and functional groups as well as their applications.
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Affiliation(s)
| | - Jing Sun
- Key Laboratory of Biobased Polymer Materials, Shandong Provincial Education Department, School of Polymer Science and Engineering, Qingdao University of Science and Technology, Qingdao 266042, China;
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4
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New Frontiers in Molecular Imaging with Superparamagnetic Iron Oxide Nanoparticles (SPIONs): Efficacy, Toxicity, and Future Applications. Nucl Med Mol Imaging 2020; 54:65-80. [PMID: 32377258 DOI: 10.1007/s13139-020-00635-w] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2019] [Revised: 12/23/2019] [Accepted: 01/22/2020] [Indexed: 12/29/2022] Open
Abstract
Supermagnetic Iron Oxide Nanoparticles (SPIONs) are nanoparticles that have an iron oxide core and a functionalized shell. SPIONs have recently raised much interest in the scientific community, given their exciting potential diagnostic and theragnostic applications. The possibility to modify their surface and the characteristics of their core make SPIONs a specific contrast agent for magnetic resonance imaging but also an intriguing family of tracer for nuclear medicine. An example is 68Ga-radiolabeled bombesin-conjugated to superparamagnetic nanoparticles coated with trimethyl chitosan that is selective for the gastrin-releasing peptide receptors. These receptors are expressed by several human cancer cells such as breast and prostate neoplasia. Since the coating does not interfere with the properties of the molecules bounded to the shell, it has been proposed to link SPIONs with antibodies. SPIONs can be used also to monitor the biodistribution of mesenchymal stromal cells and take place in various applications. The aim of this review of literature is to analyze the diagnostic aspect of SPIONs in magnetic resonance imaging and in nuclear medicine, with a particular focus on sentinel lymph node applications. Moreover, it is taken into account the possible toxicity and the effects on human physiology to determine the SPIONs' safety.
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5
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Fu YH, Perales C, Eliason T, Bergbreiter DE. 110th Anniversary: Reversible Solubilization of Polar Polymers and Polymeric Catalysts in Nonpolar Solvents. Ind Eng Chem Res 2019. [DOI: 10.1021/acs.iecr.9b02373] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Ying-Hua Fu
- Department of Chemistry, Texas A&M University, P.O. Box 30012, College Station, Texas 77842-3012, United States
| | - Camila Perales
- Department of Chemistry, Texas A&M University, P.O. Box 30012, College Station, Texas 77842-3012, United States
| | - Todd Eliason
- Department of Chemistry, Texas A&M University, P.O. Box 30012, College Station, Texas 77842-3012, United States
| | - David E. Bergbreiter
- Department of Chemistry, Texas A&M University, P.O. Box 30012, College Station, Texas 77842-3012, United States
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6
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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.
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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
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7
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Awada H, Al Samad A, Laurencin D, Gilbert R, Dumail X, El Jundi A, Bethry A, Pomrenke R, Johnson C, Lemaire L, Franconi F, Félix G, Larionova J, Guari Y, Nottelet B. Controlled Anchoring of Iron Oxide Nanoparticles on Polymeric Nanofibers: Easy Access to Core@Shell Organic-Inorganic Nanocomposites for Magneto-Scaffolds. ACS APPLIED MATERIALS & INTERFACES 2019; 11:9519-9529. [PMID: 30729776 DOI: 10.1021/acsami.8b19099] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/21/2023]
Abstract
Composites combining superparamagnetic iron oxide nanoparticles (SPIONs) and polymers are largely present in modern (bio)materials. However, although SPIONs embedded in polymer matrices are classically reported, the mechanical and degradation properties of the polymer scaffold are impacted by the SPIONs. Therefore, the controlled anchoring of SPIONs onto polymer surfaces is still a major challenge. Herein, we propose an efficient strategy for the direct and uniform anchoring of SPIONs on the surface of functionalized-polylactide (PLA) nanofibers via a simple free ligand exchange procedure to design PLA@SPIONs core@shell nanocomposites. The resulting PLA@SPIONs hybrid biomaterials are characterized by electron microscopy (scanning electron microscopy and transmission electron microscopy) and energy-dispersive X-ray spectroscopy analysis to probe the morphology and detect elements present at the organic-inorganic interface, respectively. A monolayer of SPIONs with a complete and homogeneous coverage is observed on the surface of PLA nanofibers. Magnetization experiments show that magnetic properties of the nanoparticles are well preserved after their grafting on the PLA fibers and that the size of the nanoparticles does not change. The absence of cytotoxicity, combined with a high sensitivity of detection in magnetic resonance imaging both in vitro and in vivo, makes these hybrid nanocomposites attractive for the development of magnetic biomaterials for biomedical applications.
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Affiliation(s)
- Hussein Awada
- IBMM, Université de Montpellier, CNRS, ENSCM , Montpellier , France
- ICGM, Université de Montpellier, CNRS, ENSCM , Montpellier , France
| | - Assala Al Samad
- IBMM, Université de Montpellier, CNRS, ENSCM , Montpellier , France
| | | | - Ryan Gilbert
- Department of Biomedical Engineering, Center for Biotechnology & Interdisciplinary Studies , Rensselaer Polytechnic Institute , Troy , New York 12180 , United States
| | - Xavier Dumail
- ICGM, Université de Montpellier, CNRS, ENSCM , Montpellier , France
| | - Ayman El Jundi
- IBMM, Université de Montpellier, CNRS, ENSCM , Montpellier , France
| | - Audrey Bethry
- IBMM, Université de Montpellier, CNRS, ENSCM , Montpellier , France
| | - Rebecca Pomrenke
- Department of Biomedical Engineering, Center for Biotechnology & Interdisciplinary Studies , Rensselaer Polytechnic Institute , Troy , New York 12180 , United States
| | - Christopher Johnson
- Department of Biomedical Engineering, Center for Biotechnology & Interdisciplinary Studies , Rensselaer Polytechnic Institute , Troy , New York 12180 , United States
| | - Laurent Lemaire
- Micro & Nanomédecines Translationnelles-MINT, UNIV Angers, INSERM U1066, CNRS UMR 6021 , Angers , France
- PRISM Plate-Forme de Recherche en Imagerie et Spectroscopie Multi-Modales, PRISM-Icat , Angers , France
| | - Florence Franconi
- Micro & Nanomédecines Translationnelles-MINT, UNIV Angers, INSERM U1066, CNRS UMR 6021 , Angers , France
- PRISM Plate-Forme de Recherche en Imagerie et Spectroscopie Multi-Modales, PRISM-Icat , Angers , France
| | - Gautier Félix
- ICGM, Université de Montpellier, CNRS, ENSCM , Montpellier , France
| | - Joulia Larionova
- ICGM, Université de Montpellier, CNRS, ENSCM , Montpellier , France
| | - Yannick Guari
- ICGM, Université de Montpellier, CNRS, ENSCM , Montpellier , France
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8
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Gebru H, Wang X, Li Z, Liu J, Xu J, Wang H, Xu S, Wei F, Zhu H, Guo K. Brønsted base mediated one-pot synthesis of catechol-ended amphiphilic polysarcosine-b-poly(N-butyl glycine) diblock copolypeptoids. PURE APPL CHEM 2018. [DOI: 10.1515/pac-2018-0604] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
Abstract
Catechol moiety offers a versatile platform in the preparation of functionalized polymers, but it is not usually compatible with catalysis in polymerizations. To address these challenges, we suggest employment of one Brønsted base in masking the activity of catechol moiety and to modulate the polymerization. Based on this strategy, the ring-opening polymerization (ROP) of sarcosine N-carboxyanhydrides (Sar-NCA) was carried out using dopamine hydrochloride as an initiator and triethylamine as a Brønsted base. PSar with predicted molecular weights (M
n,NMR=3.7 kg mol−1) and narrow dispersities (Đ<1.13) was prepared. Catechol initiator was successfully linked to PSar end as confirmed by MALDI-ToF MS. Subsequently, copolymerization of N-butyl glycine N-carboxyanhydrides (Bu-Gly-NCA) from the PSar in one-pot produced catechol end-functionalized amphiphilic polysarcosine-block-poly(N-butyl glycine) diblock copolypeptoids (cat-PSar-b-PGlyBu). Further, cat-PSar-b-PGlyBu enabled the aqueous dispersion of manganese oxide nanoparticles which was attributable to the anchor of the diblock copolymers onto the surface of the nanoparticles. The strategy for catechol masking and polymerization mediating by one Brønsted base offered a new avenue into the synthesis of catechol-ended block copolymers.
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Affiliation(s)
- Hailemariam Gebru
- State Key Laboratory of Materials-Oriented Chemical Engineering , College of Biotechnology and Pharmaceutical Engineering, Nanjing Tech University , 30 Puzhu Road South , Nanjing 211816 , China
- Department of Chemistry , Mizan-Tepi University , PO Box 260 , Tepi , Ethiopia
| | - Xin Wang
- State Key Laboratory of Materials-Oriented Chemical Engineering , College of Biotechnology and Pharmaceutical Engineering, Nanjing Tech University , 30 Puzhu Road South , Nanjing 211816 , China
| | - Zhenjiang Li
- State Key Laboratory of Materials-Oriented Chemical Engineering , College of Biotechnology and Pharmaceutical Engineering, Nanjing Tech University , 30 Puzhu Road South , Nanjing 211816 , China
| | - Jingjing Liu
- State Key Laboratory of Materials-Oriented Chemical Engineering , College of Biotechnology and Pharmaceutical Engineering, Nanjing Tech University , 30 Puzhu Road South , Nanjing 211816 , China
| | - Jiaxi Xu
- State Key Laboratory of Materials-Oriented Chemical Engineering , College of Biotechnology and Pharmaceutical Engineering, Nanjing Tech University , 30 Puzhu Road South , Nanjing 211816 , China
| | - Haixin Wang
- State Key Laboratory of Materials-Oriented Chemical Engineering , College of Biotechnology and Pharmaceutical Engineering, Nanjing Tech University , 30 Puzhu Road South , Nanjing 211816 , China
| | - Songquan Xu
- State Key Laboratory of Materials-Oriented Chemical Engineering , College of Biotechnology and Pharmaceutical Engineering, Nanjing Tech University , 30 Puzhu Road South , Nanjing 211816 , China
| | - Fulan Wei
- State Key Laboratory of Materials-Oriented Chemical Engineering , College of Biotechnology and Pharmaceutical Engineering, Nanjing Tech University , 30 Puzhu Road South , Nanjing 211816 , China
| | - Hui Zhu
- State Key Laboratory of Materials-Oriented Chemical Engineering , College of Biotechnology and Pharmaceutical Engineering, Nanjing Tech University , 30 Puzhu Road South , Nanjing 211816 , China
| | - Kai Guo
- State Key Laboratory of Materials-Oriented Chemical Engineering , College of Biotechnology and Pharmaceutical Engineering, Nanjing Tech University , 30 Puzhu Road South , Nanjing 211816 , China
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Sahle FF, Gulfam M, Lowe TL. Design strategies for physical-stimuli-responsive programmable nanotherapeutics. Drug Discov Today 2018; 23:992-1006. [PMID: 29653291 PMCID: PMC6195679 DOI: 10.1016/j.drudis.2018.04.003] [Citation(s) in RCA: 51] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2018] [Revised: 03/31/2018] [Accepted: 04/04/2018] [Indexed: 12/22/2022]
Abstract
Nanomaterials that respond to externally applied physical stimuli such as temperature, light, ultrasound, magnetic field and electric field have shown great potential for controlled and targeted delivery of therapeutic agents. However, the body of literature on programming these stimuli-responsive nanomaterials to attain the desired level of pharmacologic responses is still fragmented and has not been systematically reviewed. The purpose of this review is to summarize and synthesize the literature on various design strategies for simple and sophisticated programmable physical-stimuli-responsive nanotherapeutics.
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Affiliation(s)
- Fitsum Feleke Sahle
- Department of Pharmaceutical Sciences, University of Tennessee Health Sciences Center, Memphis, TN 38163, USA
| | - Muhammad Gulfam
- Department of Pharmaceutical Sciences, University of Tennessee Health Sciences Center, Memphis, TN 38163, USA
| | - Tao L Lowe
- Department of Pharmaceutical Sciences, University of Tennessee Health Sciences Center, Memphis, TN 38163, USA.
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10
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The Role of Chain Molecular Weight and Hofmeister Series Ions in Thermal Aggregation of Poly(2-Isopropyl-2-Oxazoline) Grafted Nanoparticles. Polymers (Basel) 2018; 10:polym10040451. [PMID: 30966486 PMCID: PMC6415256 DOI: 10.3390/polym10040451] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2018] [Revised: 04/10/2018] [Accepted: 04/14/2018] [Indexed: 12/22/2022] Open
Abstract
Thermoresponsive nanoparticles are promising smart materials for many applications. However, a rational design for applications requires a deeper understanding and experimental verification of the various parameters that influence the thermoresponsiveness of the spherical polymer brushes that define most of such nanomaterials. Therefore, we investigate superparamagnetic iron oxide nanoparticles (SPION) grafted with poly(2-isopropyl-2-oxazoline) (6–33 kg mol−1) by temperature-cycled dynamic light scattering and differential scanning calorimetry. The grafting of dense spherical polymer brushes leads to lower aggregation temperatures and transition enthalpies when compared with the free polymer. The transition enthalpy and temperature depend on the polymer shell size and structure. The addition of kosmotropic salts decreases the aggregation temperature following the Hofmeister series.
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Kurzhals S, Schroffenegger M, Gal N, Zirbs R, Reimhult E. Influence of Grafted Block Copolymer Structure on Thermoresponsiveness of Superparamagnetic Core-Shell Nanoparticles. Biomacromolecules 2017; 19:1435-1444. [PMID: 29161516 PMCID: PMC5954351 DOI: 10.1021/acs.biomac.7b01403] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
![]()
The
morphology and topology of thermoresponsive polymers have a
strong impact on their responsive properties. Grafting onto spherical
particles has been shown to reduce responsiveness and transition temperatures;
grafting of block copolymers has shown that switchable or retained
wettability of a surface or particle during desolvation of one block
can take place. Here, doubly thermoresponsive block copolymers were
grafted onto spherical, monodisperse, and superparamagnetic iron oxide
nanoparticles to investigate the effect of thermal desolvation on
spherical brushes of block copolymers. By inverting the block order,
the influence of core proximity on the responsive properties of the
individual blocks could be studied as well as their relative influence
on the nanoparticle colloidal stability. The inner block was shown
to experience a stronger reduction in transition temperature and transition
enthalpy compared to the outer block. Still, the outer block also
experiences a significant reduction in responsiveness due to the restricted
environment in the nanoparticle shell compared to that of the free
polymer state. The demonstrated pronounced distance dependence importantly
implies the possibility, but also the necessity, to radially tailor
polymer hydration transitions for applications such as drug delivery,
hyperthermia, and biotechnological separation for which thermally
responsive nanoparticles are being developed.
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Affiliation(s)
- Steffen Kurzhals
- Institute for Biologically Inspired Materials, Department of Nanobiotechnology , University of Natural Resources and Life Sciences, Vienna , Muthgasse 11 , 1190 Vienna , Austria
| | - Martina Schroffenegger
- Institute for Biologically Inspired Materials, Department of Nanobiotechnology , University of Natural Resources and Life Sciences, Vienna , Muthgasse 11 , 1190 Vienna , Austria
| | - Noga Gal
- Institute for Biologically Inspired Materials, Department of Nanobiotechnology , University of Natural Resources and Life Sciences, Vienna , Muthgasse 11 , 1190 Vienna , Austria
| | - Ronald Zirbs
- Institute for Biologically Inspired Materials, Department of Nanobiotechnology , University of Natural Resources and Life Sciences, Vienna , Muthgasse 11 , 1190 Vienna , Austria
| | - Erik Reimhult
- Institute for Biologically Inspired Materials, Department of Nanobiotechnology , University of Natural Resources and Life Sciences, Vienna , Muthgasse 11 , 1190 Vienna , Austria
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