1
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Kehrein J, Bunker A, Luxenhofer R. POxload: Machine Learning Estimates Drug Loadings of Polymeric Micelles. Mol Pharm 2024; 21:3356-3374. [PMID: 38805643 DOI: 10.1021/acs.molpharmaceut.4c00086] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/30/2024]
Abstract
Block copolymers, composed of poly(2-oxazoline)s and poly(2-oxazine)s, can serve as drug delivery systems; they form micelles that carry poorly water-soluble drugs. Many recent studies have investigated the effects of structural changes of the polymer and the hydrophobic cargo on drug loading. In this work, we combine these data to establish an extended formulation database. Different molecular properties and fingerprints are tested for their applicability to serve as formulation-specific mixture descriptors. A variety of classification and regression models are built for different descriptor subsets and thresholds of loading efficiency and loading capacity, with the best models achieving overall good statistics for both cross- and external validation (balanced accuracies of 0.8). Subsequently, important features are dissected for interpretation, and the DrugBank is screened for potential therapeutic use cases where these polymers could be used to develop novel formulations of hydrophobic drugs. The most promising models are provided as an open-source software tool for other researchers to test the applicability of these delivery systems for potential new drug candidates.
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Affiliation(s)
- Josef Kehrein
- Soft Matter Chemistry, Department of Chemistry, Faculty of Science, University of Helsinki, A. I. Virtasen aukio 1, 00014 Helsinki, Finland
- Drug Research Program, Division of Pharmaceutical Biosciences Faculty of Pharmacy, University of Helsinki, Viikinkaari 5 E, 00014 Helsinki, Finland
| | - Alex Bunker
- Drug Research Program, Division of Pharmaceutical Biosciences Faculty of Pharmacy, University of Helsinki, Viikinkaari 5 E, 00014 Helsinki, Finland
| | - Robert Luxenhofer
- Soft Matter Chemistry, Department of Chemistry, Faculty of Science, University of Helsinki, A. I. Virtasen aukio 1, 00014 Helsinki, Finland
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2
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Kehrein J, Gürsöz E, Davies M, Luxenhofer R, Bunker A. Unravel the Tangle: Atomistic Insight into Ultrahigh Curcumin-Loaded Polymer Micelles. SMALL (WEINHEIM AN DER BERGSTRASSE, GERMANY) 2023; 19:e2303066. [PMID: 37403298 DOI: 10.1002/smll.202303066] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/11/2023] [Revised: 06/22/2023] [Indexed: 07/06/2023]
Abstract
Amphiphilic ABA-triblock copolymers, comprised of poly(2-oxazoline) and poly(2-oxazine), can solubilize poorly water-soluble molecules in a structure-dependent manner forming micelles with exceptionally high drug loading. All-atom molecular dynamics simulations are conducted on previously experimentally characterized, curcumin-loaded micelles to dissect the structure-property relationships. Polymer-drug interactions for different levels of drug loading and variation in polymer structures of both the inner hydrophobic core and outer hydrophilic shell are investigated. In silico, the system with the highest experimental loading capacity shows the highest number of drug molecules encapsulated by the core. Furthermore, in systems with lower loading capacity outer A blocks show a greater extent of entanglement with the inner B blocks. Hydrogen bond analyses corroborate previous hypotheses: poly(2-butyl-2-oxazoline) B blocks, found experimentally to have reduced loading capacity for curcumin compared to poly(2-propyl-2-oxazine), establish fewer but longer-lasting hydrogen bonds. This possibly results from different sidechain conformations around the hydrophobic cargo, which is investigated by unsupervised machine learning to cluster monomers in smaller model systems mimicking different micelle compartments. Exchanging poly(2-methyl-2-oxazoline) with poly(2-ethyl-2-oxazoline) leads to increased drug interactions and reduced corona hydration; this suggests an impairment of micelle solubility or colloidal stability. These observations can help driving forward a more rational a priori nanoformulation design.
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Affiliation(s)
- Josef Kehrein
- Soft Matter Chemistry, Department of Chemistry, Faculty of Science, University of Helsinki, Helsinki, 00014, Finland
- Division of Pharmaceutical Biosciences, Drug Research Program, Faculty of Pharmacy, University of Helsinki, Helsinki, 00014, Finland
| | - Ekinsu Gürsöz
- Soft Matter Chemistry, Department of Chemistry, Faculty of Science, University of Helsinki, Helsinki, 00014, Finland
- Division of Pharmaceutical Biosciences, Drug Research Program, Faculty of Pharmacy, University of Helsinki, Helsinki, 00014, Finland
| | - Matthew Davies
- Department of Physics and Astronomy, The University of Western Ontario, 1151 Richmond Street, London, Ontario, N6A 5B7, Canada
| | - Robert Luxenhofer
- Soft Matter Chemistry, Department of Chemistry, Faculty of Science, University of Helsinki, Helsinki, 00014, Finland
| | - Alex Bunker
- Division of Pharmaceutical Biosciences, Drug Research Program, Faculty of Pharmacy, University of Helsinki, Helsinki, 00014, Finland
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3
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Haider MS, Mahato AK, Kotliarova A, Forster S, Böttcher B, Stahlhut P, Sidorova Y, Luxenhofer R. Biological Activity In Vitro, Absorption, BBB Penetration, and Tolerability of Nanoformulation of BT44:RET Agonist with Disease-Modifying Potential for the Treatment of Neurodegeneration. Biomacromolecules 2023; 24:4348-4365. [PMID: 36219820 PMCID: PMC10565809 DOI: 10.1021/acs.biomac.2c00761] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2022] [Revised: 09/17/2022] [Indexed: 11/29/2022]
Abstract
BT44 is a novel, second-generation glial cell line-derived neurotropic factor mimetic with improved biological activity and is a lead compound for the treatment of neurodegenerative disorders. Like many other small molecules, it suffers from intrinsic poor aqueous solubility, posing significant hurdles at various levels for its preclinical development and clinical translation. Herein, we report a poly(2-oxazoline)s (POx)-based BT44 micellar nanoformulation with an ultrahigh drug-loading capacity of 47 wt %. The BT44 nanoformulation was comprehensively characterized by 1H NMR spectroscopy, differential scanning calorimetry (DSC), powder X-ray diffraction (XRD), dynamic light scattering (DLS), and cryo-transmission/scanning electron microscopy (cryo-TEM/SEM). The DSC, XRD, and redispersion studies collectively confirmed that the BT44 formulation can be stored as a lyophilized powder and can be redispersed upon need. The DLS suggested that the redispersed formulation is suitable for parenteral administration (Dh ≈ 70 nm). The cryo-TEM measurements showed the presence of wormlike structures in both the plain polymer and the BT44 formulation. The BT44 formulation retained biological activity in immortalized cells and in cultured dopamine neurons. The micellar nanoformulation of BT44 exhibited improved absorption (after subcutaneous injection) and blood-brain barrier (BBB) penetration, and no acute toxic effects in mice were observed. In conclusion, herein, we have developed an ultrahigh BT44-loaded aqueous injectable nanoformulation, which can be used to pave the way for its preclinical and clinical development for the management of neurodegenerative disorders.
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Affiliation(s)
- Malik Salman Haider
- Functional
Polymer Materials, Chair for Advanced Materials Synthesis, Institute
for Functional Materials and Biofabrication, Department of Chemistry
and Pharmacy, Julius-Maximilians-University
Würzburg, Röntgenring
11, 97070Würzburg, Germany
- University
Hospital of Würzburg, Department of Ophthalmology, Josef-Schneider-Street 11, D-97080Würzburg, Germany
| | - Arun Kumar Mahato
- Laboratory
of Molecular Neuroscience, Institute of Biotechnology, HiLIFE, University of Helsinki, 00014Helsinki, Finland
| | - Anastasiia Kotliarova
- Laboratory
of Molecular Neuroscience, Institute of Biotechnology, HiLIFE, University of Helsinki, 00014Helsinki, Finland
| | - Stefan Forster
- Functional
Polymer Materials, Chair for Advanced Materials Synthesis, Institute
for Functional Materials and Biofabrication, Department of Chemistry
and Pharmacy, Julius-Maximilians-University
Würzburg, Röntgenring
11, 97070Würzburg, Germany
| | - Bettina Böttcher
- Biocenter
and Rudolf Virchow Centre, Julius-Maximilians-University
Würzburg, Haus
D15, Josef-Schneider-Strasse 2, 97080Würzburg, Germany
| | - Philipp Stahlhut
- Department
of Functional Materials in Medicine and Dentistry, Institute of Functional
Materials and Biofabrication and Bavarian Polymer Institute, Julius-Maximilians-University Würzburg, Pleicherwall 2, 97070Würzburg, Germany
| | - Yulia Sidorova
- Laboratory
of Molecular Neuroscience, Institute of Biotechnology, HiLIFE, University of Helsinki, 00014Helsinki, Finland
| | - Robert Luxenhofer
- Functional
Polymer Materials, Chair for Advanced Materials Synthesis, Institute
for Functional Materials and Biofabrication, Department of Chemistry
and Pharmacy, Julius-Maximilians-University
Würzburg, Röntgenring
11, 97070Würzburg, Germany
- Soft
Matter Chemistry, Department of Chemistry, and Helsinki Institute
of Sustainability Science, Faculty of Science, University of Helsinki, PB 55-00014Helsinki, Finland
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4
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The in vivo fate of polymeric micelles. Adv Drug Deliv Rev 2022; 188:114463. [PMID: 35905947 DOI: 10.1016/j.addr.2022.114463] [Citation(s) in RCA: 33] [Impact Index Per Article: 16.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2022] [Revised: 06/10/2022] [Accepted: 07/15/2022] [Indexed: 12/12/2022]
Abstract
This review aims to provide a systemic analysis of the in vivo, as well as subcellular, fate of polymeric micelles (PMs), starting from the entry of PMs into the body. Few PMs are able to cross the biological barriers intact and reach the circulation. In the blood, PMs demonstrate fairly good stability mainly owing to formation of protein corona despite controversial results reported by different groups. Although the exterior hydrophilic shells render PMs "long-circulating", the biodistribution of PMs into the mononuclear phagocyte systems (MPS) is dominant as compared with non-MPS organs and tissues. Evidence emerges to support that the copolymer poly(ethylene glycol)-poly(lactic acid) (PEG-PLA) is first broken down into pieces of PEG and PLA and then remnants to be eliminated from the body finally. At the cellular level, PMs tend to be internalized via endocytosis due to their particulate nature and disassembled and degraded within the cell. Recent findings on the effect of particle size, surface characteristics and shape are also reviewed. It is envisaged that unraveling the in vivo and subcellular fate sheds light on the performing mechanisms and gears up the clinical translation of PMs.
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5
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Yang M, Haider MS, Forster S, Hu C, Luxenhofer R. Synthesis and Investigation of Chiral Poly(2,4-disubstituted-2-oxazoline)-Based Triblock Copolymers, Their Self-Assembly, and Formulation with Chiral and Achiral Drugs. Macromolecules 2022. [DOI: 10.1021/acs.macromol.2c00229] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Mengshi Yang
- Functional Polymer Materials, Chair for Chemical Technology of Material Synthesis, Institute for Functional Materials and Biofabrication, Department of Chemistry and Pharmacy, Julius-Maximilians-University Würzburg, Röntgenring 11, 97070 Würzburg, Germany
| | - Malik Salman Haider
- Functional Polymer Materials, Chair for Chemical Technology of Material Synthesis, Institute for Functional Materials and Biofabrication, Department of Chemistry and Pharmacy, Julius-Maximilians-University Würzburg, Röntgenring 11, 97070 Würzburg, Germany
| | - Stefan Forster
- Functional Polymer Materials, Chair for Chemical Technology of Material Synthesis, Institute for Functional Materials and Biofabrication, Department of Chemistry and Pharmacy, Julius-Maximilians-University Würzburg, Röntgenring 11, 97070 Würzburg, Germany
| | - Chen Hu
- Functional Polymer Materials, Chair for Chemical Technology of Material Synthesis, Institute for Functional Materials and Biofabrication, Department of Chemistry and Pharmacy, Julius-Maximilians-University Würzburg, Röntgenring 11, 97070 Würzburg, Germany
| | - Robert Luxenhofer
- Functional Polymer Materials, Chair for Chemical Technology of Material Synthesis, Institute for Functional Materials and Biofabrication, Department of Chemistry and Pharmacy, Julius-Maximilians-University Würzburg, Röntgenring 11, 97070 Würzburg, Germany
- Soft Matter Chemistry, Department of Chemistry and Helsinki Institute of Sustainability Science, Faculty of Science, University of Helsinki, P.O. Box 55, 00014 Helsinki, Finland
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6
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Mazrad ZAI, Schelle B, Nicolazzo JA, Leiske MN, Kempe K. Nitrile-Functionalized Poly(2-oxazoline)s as a Versatile Platform for the Development of Polymer Therapeutics. Biomacromolecules 2021; 22:4618-4632. [PMID: 34647734 DOI: 10.1021/acs.biomac.1c00923] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
In recent years, polymers bearing reactive groups have received significant interest for biomedical applications. Numerous functional polymer platforms have been introduced, which allow for the preparation of materials with tailored properties via post-polymerization modifications. However, because of their reactivity, many functional groups are not compatible with the initial polymerization. The nitrile group is a highly interesting and relatively inert functionality that has mainly received attention in radical polymerizations. In this Article, a nitrile-functionalized 2-oxazoline monomer (2-(4-nitrile-butyl)-2-oxazoline, BuNiOx) is introduced, and its compatibility with the cationic ring-opening polymerization is demonstrated. Subsequently, the versatility of nitrile-functionalized poly(2-oxazoline)s (POx) is presented. To this end, diverse (co)polymers are synthesized and characterized by nuclear resonance spectroscopy, size-exclusion chromatography, and mass spectrometry. Amphiphilic block copolymers are shown to efficiently encapsulate the hydrophobic drug curcumin (CUR) in aqueous solution, and the anti-inflammatory effect of the CUR-containing nanostructures is presented in BV-2 microglia. Furthermore, the availability of the BuNiOx repeating units for post-polymerization modifications with hydroxylamine to yield amidoxime (AO)-functionalized POx is demonstrated. These AO-containing POx were successfully applied for the complexation of Fe(III) in a quantitative manner. In addition, AO-functionalized POx were shown to release nitric oxide intracellularly in BV-2 microglia. Thus nitrile-functionalized POx represent a promising and robust platform for the design of polymer therapeutics for a wide range of applications.
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Affiliation(s)
- Zihnil A I Mazrad
- ARC Centre of Excellence in Convergent Bio-Nano Science & Technology, Monash University, Parkville, Victoria 3052, Australia.,Drug Delivery, Disposition and Dynamics, Monash Institute of Pharmaceutical Sciences, Monash University, Parkville, Victoria 3052, Australia
| | - Baptiste Schelle
- ARC Centre of Excellence in Convergent Bio-Nano Science & Technology, Monash University, Parkville, Victoria 3052, Australia.,Drug Delivery, Disposition and Dynamics, Monash Institute of Pharmaceutical Sciences, Monash University, Parkville, Victoria 3052, Australia
| | - Joseph A Nicolazzo
- Drug Delivery, Disposition and Dynamics, Monash Institute of Pharmaceutical Sciences, Monash University, Parkville, Victoria 3052, Australia
| | - Meike N Leiske
- ARC Centre of Excellence in Convergent Bio-Nano Science & Technology, Monash University, Parkville, Victoria 3052, Australia.,Drug Delivery, Disposition and Dynamics, Monash Institute of Pharmaceutical Sciences, Monash University, Parkville, Victoria 3052, Australia
| | - Kristian Kempe
- ARC Centre of Excellence in Convergent Bio-Nano Science & Technology, Monash University, Parkville, Victoria 3052, Australia.,Drug Delivery, Disposition and Dynamics, Monash Institute of Pharmaceutical Sciences, Monash University, Parkville, Victoria 3052, Australia.,Materials Science and Engineering, Monash University, Clayton, Victoria 3800, Australia
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7
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Hahn L, Keßler L, Polzin L, Fritze L, Forster S, Helten H, Luxenhofer R. ABA Type Amphiphiles with Poly(2‐benzhydryl‐2‐oxazine) Moieties: Synthesis, Characterization and Inverse Thermogelation. MACROMOL CHEM PHYS 2021. [DOI: 10.1002/macp.202100114] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Affiliation(s)
- Lukas Hahn
- Functional Polymer Materials, Chair for Advanced Materials Synthesis, Institute for Functional Materials and Biofabrication, Department of Chemistry and Pharmacy Julius‐Maximilians‐University Würzburg Röntgenring 11 Würzburg 97070 Germany
| | - Larissa Keßler
- Functional Polymer Materials, Chair for Advanced Materials Synthesis, Institute for Functional Materials and Biofabrication, Department of Chemistry and Pharmacy Julius‐Maximilians‐University Würzburg Röntgenring 11 Würzburg 97070 Germany
- Soft Matter Chemistry, Department of Chemistry and Helsinki Institute of Sustainability Science, Faculty of Science University of Helsinki P.O. Box 55 Helsinki 00014 Finland
| | - Lando Polzin
- Functional Polymer Materials, Chair for Advanced Materials Synthesis, Institute for Functional Materials and Biofabrication, Department of Chemistry and Pharmacy Julius‐Maximilians‐University Würzburg Röntgenring 11 Würzburg 97070 Germany
| | - Lars Fritze
- Institute of Inorganic Chemistry and Institute for Sustainable Chemistry & Catalysis with Boron (ICB) Julius‐Maximilians‐University Würzburg Am Hubland Würzburg 97074 Germany
| | - Stefan Forster
- Functional Polymer Materials, Chair for Advanced Materials Synthesis, Institute for Functional Materials and Biofabrication, Department of Chemistry and Pharmacy Julius‐Maximilians‐University Würzburg Röntgenring 11 Würzburg 97070 Germany
| | - Holger Helten
- Institute of Inorganic Chemistry and Institute for Sustainable Chemistry & Catalysis with Boron (ICB) Julius‐Maximilians‐University Würzburg Am Hubland Würzburg 97074 Germany
| | - Robert Luxenhofer
- Functional Polymer Materials, Chair for Advanced Materials Synthesis, Institute for Functional Materials and Biofabrication, Department of Chemistry and Pharmacy Julius‐Maximilians‐University Würzburg Röntgenring 11 Würzburg 97070 Germany
- Soft Matter Chemistry, Department of Chemistry and Helsinki Institute of Sustainability Science, Faculty of Science University of Helsinki P.O. Box 55 Helsinki 00014 Finland
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8
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Haider MS, Ahmad T, Yang M, Hu C, Hahn L, Stahlhut P, Groll J, Luxenhofer R. Tuning the Thermogelation and Rheology of Poly(2-Oxazoline)/Poly(2-Oxazine)s Based Thermosensitive Hydrogels for 3D Bioprinting. Gels 2021; 7:78. [PMID: 34202652 PMCID: PMC8293086 DOI: 10.3390/gels7030078] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2021] [Revised: 06/09/2021] [Accepted: 06/15/2021] [Indexed: 12/28/2022] Open
Abstract
As one kind of "smart" material, thermogelling polymers find applications in biofabrication, drug delivery and regenerative medicine. In this work, we report a thermosensitive poly(2-oxazoline)/poly(2-oxazine) based diblock copolymer comprising thermosensitive/moderately hydrophobic poly(2-N-propyl-2-oxazine) (pPrOzi) and thermosensitive/moderately hydrophilic poly(2-ethyl-2-oxazoline) (pEtOx). Hydrogels were only formed when block length exceeded certain length (≈100 repeat units). The tube inversion and rheological tests showed that the material has then a reversible sol-gel transition above 25 wt.% concentration. Rheological tests further revealed a gel strength around 3 kPa, high shear thinning property and rapid shear recovery after stress, which are highly desirable properties for extrusion based three-dimensional (3D) (bio) printing. Attributed to the rheology profile, well resolved printability and high stackability (with added laponite) was also possible. (Cryo) scanning electron microscopy exhibited a highly porous, interconnected, 3D network. The sol-state at lower temperatures (in ice bath) facilitated the homogeneous distribution of (fluorescently labelled) human adipose derived stem cells (hADSCs) in the hydrogel matrix. Post-printing live/dead assays revealed that the hADSCs encapsulated within the hydrogel remained viable (≈97%). This thermoreversible and (bio) printable hydrogel demonstrated promising properties for use in tissue engineering applications.
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Affiliation(s)
- Malik Salman Haider
- Functional Polymer Materials, Chair for Advanced Materials Synthesis, Institute for Functional Materials and Biofabrication, Department of Chemistry and Pharmacy, Julius-Maximilians-University Würzburg, Röntgenring 11, 97070 Würzburg, Germany; (M.Y.); (C.H.); (L.H.)
| | - Taufiq Ahmad
- Department of Functional Materials in Medicine and Dentistry, Institute for Functional Materials and Biofabrication and Bavarian Polymer Institute, Julius-Maximilians-University Würzburg, Pleicherwall 2, 97070 Würzburg, Germany; (T.A.); (P.S.); (J.G.)
| | - Mengshi Yang
- Functional Polymer Materials, Chair for Advanced Materials Synthesis, Institute for Functional Materials and Biofabrication, Department of Chemistry and Pharmacy, Julius-Maximilians-University Würzburg, Röntgenring 11, 97070 Würzburg, Germany; (M.Y.); (C.H.); (L.H.)
| | - Chen Hu
- Functional Polymer Materials, Chair for Advanced Materials Synthesis, Institute for Functional Materials and Biofabrication, Department of Chemistry and Pharmacy, Julius-Maximilians-University Würzburg, Röntgenring 11, 97070 Würzburg, Germany; (M.Y.); (C.H.); (L.H.)
| | - Lukas Hahn
- Functional Polymer Materials, Chair for Advanced Materials Synthesis, Institute for Functional Materials and Biofabrication, Department of Chemistry and Pharmacy, Julius-Maximilians-University Würzburg, Röntgenring 11, 97070 Würzburg, Germany; (M.Y.); (C.H.); (L.H.)
| | - Philipp Stahlhut
- Department of Functional Materials in Medicine and Dentistry, Institute for Functional Materials and Biofabrication and Bavarian Polymer Institute, Julius-Maximilians-University Würzburg, Pleicherwall 2, 97070 Würzburg, Germany; (T.A.); (P.S.); (J.G.)
| | - Jürgen Groll
- Department of Functional Materials in Medicine and Dentistry, Institute for Functional Materials and Biofabrication and Bavarian Polymer Institute, Julius-Maximilians-University Würzburg, Pleicherwall 2, 97070 Würzburg, Germany; (T.A.); (P.S.); (J.G.)
| | - Robert Luxenhofer
- Functional Polymer Materials, Chair for Advanced Materials Synthesis, Institute for Functional Materials and Biofabrication, Department of Chemistry and Pharmacy, Julius-Maximilians-University Würzburg, Röntgenring 11, 97070 Würzburg, Germany; (M.Y.); (C.H.); (L.H.)
- Soft Matter Chemistry, Department of Chemistry and Helsinki Institute of Sustainability Science, Faculty of Science, University of Helsinki, PB 55, 00014 Helsinki, Finland
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9
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Poly(2-oxazine)s: A comprehensive overview of the polymer structures, physical properties and applications. Eur Polym J 2021. [DOI: 10.1016/j.eurpolymj.2021.110299] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
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10
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Zahoranová A, Luxenhofer R. Poly(2-oxazoline)- and Poly(2-oxazine)-Based Self-Assemblies, Polyplexes, and Drug Nanoformulations-An Update. Adv Healthc Mater 2021; 10:e2001382. [PMID: 33448122 DOI: 10.1002/adhm.202001382] [Citation(s) in RCA: 36] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2020] [Revised: 10/03/2020] [Indexed: 12/30/2022]
Abstract
For many decades, poly(2-oxazoline)s and poly(2-oxazine)s, two closely related families of polymers, have led the life of a rather obscure research topic with only a few research groups world-wide working with them. This has changed in the last five to ten years, presumably triggered significantly by very promising clinical trials of the first poly(2-oxazoline)-based drug conjugate. The huge chemical and structural toolbox poly(2-oxazoline)s and poly(2-oxazine)s has been extended very significantly in the last few years, but their potential still remains largely untapped. Here, specifically, the developments in macromolecular self-assemblies and non-covalent drug delivery systems such as polyplexes and drug nanoformulations based on poly(2-oxazoline)s and poly(2-oxazine)s are reviewed. This highly dynamic field benefits particularly from the extensive synthetic toolbox poly(2-oxazoline)s and poly(2-oxazine)s offer and also may have the largest potential for a further development. It is expected that the research dynamics will remain high in the next few years, particularly as more about the safety and therapeutic potential of poly(2-oxazoline)s and poly(2-oxazine)s is learned.
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Affiliation(s)
- Anna Zahoranová
- Institute of Applied Synthetic Chemistry Vienna University of Technology Getreidemarkt 9/163MC Vienna 1060 Austria
| | - Robert Luxenhofer
- Functional Polymer Materials Chair for Advanced Materials Synthesis Institute for Functional Materials and Biofabrication Department of Chemistry and Pharmacy Julius‐Maximilians‐Universität Würzburg Röntgenring 11 Würzburg 97070 Germany
- Soft Matter Chemistry Department of Chemistry Helsinki University Helsinki 00014 Finland
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11
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Slor G, Olea AR, Pujals S, Tigrine A, De La Rosa VR, Hoogenboom R, Albertazzi L, Amir RJ. Judging Enzyme-Responsive Micelles by Their Covers: Direct Comparison of Dendritic Amphiphiles with Different Hydrophilic Blocks. Biomacromolecules 2021; 22:1197-1210. [PMID: 33512161 PMCID: PMC7944483 DOI: 10.1021/acs.biomac.0c01708] [Citation(s) in RCA: 20] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
![]()
Enzymatically
degradable polymeric micelles have great potential
as drug delivery systems, allowing the selective release of their
active cargo at the site of disease. Furthermore, enzymatic degradation
of the polymeric nanocarriers facilitates clearance of the delivery
system after it has completed its task. While extensive research is
dedicated toward the design and study of the enzymatically degradable
hydrophobic block, there is limited understanding on how the hydrophilic
shell of the micelle can affect the properties of such enzymatically
degradable micelles. In this work, we report a systematic head-to-head
comparison of well-defined polymeric micelles with different polymeric
shells and two types of enzymatically degradable hydrophobic cores.
To carry out this direct comparison, we developed a highly modular
approach for preparing clickable, spectrally active enzyme-responsive
dendrons with adjustable degree of hydrophobicity. The dendrons were
linked with three different widely used hydrophilic polymers—poly(ethylene
glycol), poly(2-ethyl-2-oxazoline), and poly(acrylic acid) using the
CuAAC click reaction. The high modularity and molecular precision
of the synthetic methodology enabled us to easily prepare well-defined
amphiphiles that differ either in their hydrophilic block composition
or in their hydrophobic dendron. The micelles of the different amphiphiles
were thoroughly characterized and their sizes, critical micelle concentrations,
drug loading, stability, and cell internalization were compared. We
found that the micelle diameter was almost solely dependent on the
hydrophobicity of the dendritic hydrophobic block, whereas the enzymatic
degradation rate was strongly dependent on the composition of both
blocks. Drug encapsulation capacity was very sensitive to the type
of the hydrophilic block, indicating that, in addition to the hydrophobic
core, the micellar shell also has a significant role in drug encapsulation.
Incubation of the spectrally active micelles in the presence of cells
showed that the hydrophilic shell significantly affects the micellar
stability, localization, cell internalization kinetics, and the cargo
release mechanism. Overall, the high molecular precision and the ability
of these amphiphiles to report their disassembly, even in complex
biological media, allowed us to directly compare the different types
of micelles, providing striking insights into how the composition
of the micelle shells and cores can affect their properties and potential
to serve as nanocarriers.
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Affiliation(s)
- Gadi Slor
- Department of Organic Chemistry, School of Chemistry, Faculty of Exact Sciences, Tel-Aviv University, Tel-Aviv 6997801, Israel.,Tel Aviv University Center for Nanoscience and Nanotechnology, Tel-Aviv University, Tel-Aviv 6997801, Israel
| | - Alis R Olea
- Institute for Bioengineering of Catalonia (IBEC), The Barcelona Institute of Science and Technology, Baldiri Reixac 15-21, 08028 Barcelona, Spain
| | - Sílvia Pujals
- Institute for Bioengineering of Catalonia (IBEC), The Barcelona Institute of Science and Technology, Baldiri Reixac 15-21, 08028 Barcelona, Spain.,Department of Electronic and Biomedical Engineering, Faculty of Physics, University of Barcelona, Carrer Martí I Franquès 1, 08028 Barcelona, Spain
| | - Ali Tigrine
- Supramolecular Chemistry Group, Centre of Macromolecular Chemistry (CMaC), Department of Organic and Macromolecular Chemistry, Ghent University, Krijgslaan 281 S4, B-9000 Ghent, Belgium
| | - Victor R De La Rosa
- Supramolecular Chemistry Group, Centre of Macromolecular Chemistry (CMaC), Department of Organic and Macromolecular Chemistry, Ghent University, Krijgslaan 281 S4, B-9000 Ghent, Belgium
| | - Richard Hoogenboom
- Supramolecular Chemistry Group, Centre of Macromolecular Chemistry (CMaC), Department of Organic and Macromolecular Chemistry, Ghent University, Krijgslaan 281 S4, B-9000 Ghent, Belgium
| | - Lorenzo Albertazzi
- Institute for Bioengineering of Catalonia (IBEC), The Barcelona Institute of Science and Technology, Baldiri Reixac 15-21, 08028 Barcelona, Spain.,Department of Biomedical Engineering, Institute of Complex Molecular Systems (ICMS), Eindhoven University of Technology (TUE), Eindhoven 5612 AZ, The Netherlands
| | - Roey J Amir
- Department of Organic Chemistry, School of Chemistry, Faculty of Exact Sciences, Tel-Aviv University, Tel-Aviv 6997801, Israel.,Tel Aviv University Center for Nanoscience and Nanotechnology, Tel-Aviv University, Tel-Aviv 6997801, Israel.,BLAVATNIK Center for Drug Discovery, Tel-Aviv University, Tel-Aviv 6997801, Israel.,ADAMA Center for Novel Delivery Systems in Crop Protection, Tel-Aviv University, Tel-Aviv 6997801, Israel.,The Center for Physics and Chemistry of Living Systems, Tel-Aviv University, Tel-Aviv 6997801, Israel
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12
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Haider MS, Lübtow MM, Endres S, Forster S, Flegler VJ, Böttcher B, Aseyev V, Pöppler AC, Luxenhofer R. Think Beyond the Core: Impact of the Hydrophilic Corona on Drug Solubilization Using Polymer Micelles. ACS APPLIED MATERIALS & INTERFACES 2020; 12:24531-24543. [PMID: 32378873 DOI: 10.1021/acsami.9b22495] [Citation(s) in RCA: 30] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
Polymeric micelles are typically characterized as core-shell structures. The hydrophobic core is considered as a depot for hydrophobic molecules, and the corona-forming block acts as a stabilizing and solubilizing interface between the core and aqueous milieu. Tremendous efforts have been made to tune the hydrophobic block to increase the drug loading and stability of micelles, whereas the role of hydrophilic blocks is rarely investigated in this context, with poly(ethylene glycol) (PEG) being the gold standard of hydrophilic polymers. To better understand the role of the hydrophilic corona, a small library of structurally similar A-B-A-type amphiphiles based on poly(2-oxazoline)s and poly(2-oxazine)s is investigated by varying the hydrophilic block A utilizing poly(2-methyl-2-oxazoline) (pMeOx; A) or poly(2-ethyl-2-oxazoline) (pEtOx; A*). In terms of hydrophilicity, both polymers closely resemble PEG. The more hydrophobic block B bears either a poly(2-oxazoline) and poly(2-oxazine) backbone with C3 (propyl) and C4 (butyl) side chains. Surprisingly, major differences in loading capacities from A-B-A > A*-B-A > A*-B-A* is observed for the formulation with two poorly water-soluble compounds, curcumin and paclitaxel, highlighting the importance of the hydrophilic corona of polymer micelles used for drug formulation. The formulations are also characterized by various nuclear magnetic resonance spectroscopy methods, dynamic light scattering, cryogenic transmission electron microscopy, and (micro) differential scanning calorimetry. Our findings suggest that the interaction between the hydrophilic block and the guest molecule should be considered an important, but previously largely ignored, factor for the rational design of polymeric micelles.
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Affiliation(s)
- Malik Salman Haider
- Functional Polymer Materials, Chair for Chemical Technology of Material Synthesis and Bavarian Polymer Institute, Faculty of Chemistry and Pharmacy, University of Würzburg, Röntgenring 11, 97070 Würzburg, Germany
| | - Michael M Lübtow
- Functional Polymer Materials, Chair for Chemical Technology of Material Synthesis and Bavarian Polymer Institute, Faculty of Chemistry and Pharmacy, University of Würzburg, Röntgenring 11, 97070 Würzburg, Germany
| | - Sebastian Endres
- Institute of Organic Chemistry, Faculty of Chemistry and Pharmacy, University of Würzburg, Am Hubland, 97074 Würzburg, Germany
| | - Stefan Forster
- Functional Polymer Materials, Chair for Chemical Technology of Material Synthesis and Bavarian Polymer Institute, Faculty of Chemistry and Pharmacy, University of Würzburg, Röntgenring 11, 97070 Würzburg, Germany
| | - Vanessa J Flegler
- Biocenter and Rudolf Virchow Centre, University of Würzburg, Haus D15, Josef-Schneider-Str. 2, 97080 Würzburg, Germany
| | - Bettina Böttcher
- Biocenter and Rudolf Virchow Centre, University of Würzburg, Haus D15, Josef-Schneider-Str. 2, 97080 Würzburg, Germany
| | - Vladimir Aseyev
- Department of Chemistry, University of Helsinki, PB 55, Helsinki FIN-00014, Finland
| | - Ann-Christin Pöppler
- Institute of Organic Chemistry, Faculty of Chemistry and Pharmacy, University of Würzburg, Am Hubland, 97074 Würzburg, Germany
| | - Robert Luxenhofer
- Functional Polymer Materials, Chair for Chemical Technology of Material Synthesis and Bavarian Polymer Institute, Faculty of Chemistry and Pharmacy, University of Würzburg, Röntgenring 11, 97070 Würzburg, Germany
- Department of Chemistry, University of Helsinki, PB 55, Helsinki FIN-00014, Finland
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13
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Lübtow MM, Oerter S, Quader S, Jeanclos E, Cubukova A, Krafft M, Haider MS, Schulte C, Meier L, Rist M, Sampetrean O, Kinoh H, Gohla A, Kataoka K, Appelt-Menzel A, Luxenhofer R. In Vitro Blood–Brain Barrier Permeability and Cytotoxicity of an Atorvastatin-Loaded Nanoformulation Against Glioblastoma in 2D and 3D Models. Mol Pharm 2020; 17:1835-1847. [DOI: 10.1021/acs.molpharmaceut.9b01117] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Affiliation(s)
- Michael M. Lübtow
- Functional Polymer Materials, Chair for Advanced Materials Synthesis, Department of Chemistry and Pharmacy and Bavarian Polymer Institute, University of Würzburg, Röntgenring 11, 97070 Würzburg, Germany
| | - Sabrina Oerter
- Chair Tissue Engineering and Regenerative Medicine (TERM), University Hospital Würzburg, Röntgenring 11, 97070 Würzburg, Germany
| | - Sabina Quader
- Innovation Center of Nanomedicine (iCONM), Kawasaki Institute of Industrial Promotion, 3-25-14 Tonomachi, Kawasaki-Ku, Kawasaki-Shi 210-0821, Japan
| | - Elisabeth Jeanclos
- Institute of Pharmacology and Toxicology, University of Würzburg, Versbacher Straße 9, 97078 Würzburg, Germany
- Rudolf Virchow Center for Experimental Biomedicine, University of Würzburg, Josef-Schneider-Straße 2, 97080 Würzburg, Germany
| | - Alevtina Cubukova
- Fraunhofer Institute for Silicate Research ISC, Translational Center Regenerative Therapies TLC-RT, Röntgenring 11, 97070 Würzburg, Germany
| | - Marion Krafft
- Chair Tissue Engineering and Regenerative Medicine (TERM), University Hospital Würzburg, Röntgenring 11, 97070 Würzburg, Germany
| | - Malik Salman Haider
- Functional Polymer Materials, Chair for Advanced Materials Synthesis, Department of Chemistry and Pharmacy and Bavarian Polymer Institute, University of Würzburg, Röntgenring 11, 97070 Würzburg, Germany
| | - Clemens Schulte
- Functional Polymer Materials, Chair for Advanced Materials Synthesis, Department of Chemistry and Pharmacy and Bavarian Polymer Institute, University of Würzburg, Röntgenring 11, 97070 Würzburg, Germany
| | - Laura Meier
- Functional Polymer Materials, Chair for Advanced Materials Synthesis, Department of Chemistry and Pharmacy and Bavarian Polymer Institute, University of Würzburg, Röntgenring 11, 97070 Würzburg, Germany
| | - Maximilian Rist
- Functional Polymer Materials, Chair for Advanced Materials Synthesis, Department of Chemistry and Pharmacy and Bavarian Polymer Institute, University of Würzburg, Röntgenring 11, 97070 Würzburg, Germany
| | - Oltea Sampetrean
- Institute for Advanced Medical Research (IAMR), Division of Gene Regulation, Keio University School of Medicine, 35 Shinanomachi, Shinjuku-ku, Tokyo 160-8582, Japan
| | - Hiroaki Kinoh
- Innovation Center of Nanomedicine (iCONM), Kawasaki Institute of Industrial Promotion, 3-25-14 Tonomachi, Kawasaki-Ku, Kawasaki-Shi 210-0821, Japan
| | - Antje Gohla
- Institute of Pharmacology and Toxicology, University of Würzburg, Versbacher Straße 9, 97078 Würzburg, Germany
| | - Kazunori Kataoka
- Innovation Center of Nanomedicine (iCONM), Kawasaki Institute of Industrial Promotion, 3-25-14 Tonomachi, Kawasaki-Ku, Kawasaki-Shi 210-0821, Japan
- Policy Alternatives Research Institute, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033, Japan
| | - Antje Appelt-Menzel
- Chair Tissue Engineering and Regenerative Medicine (TERM), University Hospital Würzburg, Röntgenring 11, 97070 Würzburg, Germany
- Fraunhofer Institute for Silicate Research ISC, Translational Center Regenerative Therapies TLC-RT, Röntgenring 11, 97070 Würzburg, Germany
| | - Robert Luxenhofer
- Functional Polymer Materials, Chair for Advanced Materials Synthesis, Department of Chemistry and Pharmacy and Bavarian Polymer Institute, University of Würzburg, Röntgenring 11, 97070 Würzburg, Germany
- Soft Matter Chemistry, Department of Chemistry, University of Helsinki, 00014 Helsinki, Finland
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14
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Sochor B, Düdükcü Ö, Lübtow MM, Schummer B, Jaksch S, Luxenhofer R. Probing the Complex Loading-Dependent Structural Changes in Ultrahigh Drug-Loaded Polymer Micelles by Small-Angle Neutron Scattering. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2020; 36:3494-3503. [PMID: 32203667 DOI: 10.1021/acs.langmuir.9b03460] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
Drug-loaded polymer micelles or nanoparticles are being continuously explored in the fields of drug delivery and nanomedicine. Commonly, a simple core-shell structure is assumed, in which the core incorporates the drug and the corona provides steric shielding, colloidal stability, and prevents protein adsorption. Recently, the interactions of the dissolved drug with the micellar corona have received increasing attention. Here, using small-angle neutron scattering, we provide an in-depth study of the differences in polymer micelle morphology of a small selection of structurally closely related polymer micelles at different loadings with the model compound curcumin. This work supports a previous study using solid-state nuclear magnetic resonance spectroscopy and we confirm that the drug resides predominantly in the core of the micelle at low drug loading. As the drug loading increases, neutron scattering data suggests that an inner shell is formed, which we interpret as the corona also starting to incorporate the drug, whereas the outer shell mainly contains water and the polymer. The presented data clearly shows that a better understanding of the inner morphology and the impact of the hydrophilic block can be important parameters for improved drug loading in polymer micelles as well as provide insights into the structure-property relationship.
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Affiliation(s)
- Benedikt Sochor
- Chair of X-Ray Microscopy, Department of Physics and Astronomy, University Würzburg, Campus Hubland Nord, Josef-Martin-Weg 63, 97074 Würzburg, Germany
| | - Özgür Düdükcü
- Chair of X-Ray Microscopy, Department of Physics and Astronomy, University Würzburg, Campus Hubland Nord, Josef-Martin-Weg 63, 97074 Würzburg, Germany
| | - Michael M Lübtow
- Functional Polymer Materials, Chair for Advanced Materials Synthesis, Department of Chemistry and Pharmacy and Bavarian Polymer Institute, University of Würzburg, Röntgenring 11, 97070 Würzburg, Germany
| | - Bernhard Schummer
- Fraunhofer Institute for Integrated Circuits, X-Ray Development Center EZRT, Flugplatzstraße 75, 90768 Fürth, Germany
| | - Sebastian Jaksch
- Forschungszentrum Jülich GmbH, Jülich Center for Neutron Science (JCNS) at Heinz Maier-Leibnitz Zentrum, Lichtenberstraße 1, 85747 Garching, Germany
| | - Robert Luxenhofer
- Functional Polymer Materials, Chair for Advanced Materials Synthesis, Department of Chemistry and Pharmacy and Bavarian Polymer Institute, University of Würzburg, Röntgenring 11, 97070 Würzburg, Germany
- Soft Matter Chemistry, Department of Chemistry, University of Helsinki, 00014 Helsinki, Finland
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15
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Oleszko-Torbus N, Utrata-Wesołek A, Bochenek M, Lipowska-Kur D, Dworak A, Wałach W. Thermal and crystalline properties of poly(2-oxazoline)s. Polym Chem 2020. [DOI: 10.1039/c9py01316d] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The review gathers together data concerning the influence of poly(2-substituted-2-oxazoline)s structure on their thermal and crystalline properties, and how this relationship can be adjusted in controlled manner.
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Affiliation(s)
| | | | - Marcelina Bochenek
- Centre of Polymer and Carbon Materials
- Polish Academy of Sciences
- 41-819 Zabrze
- Poland
| | - Daria Lipowska-Kur
- Centre of Polymer and Carbon Materials
- Polish Academy of Sciences
- 41-819 Zabrze
- Poland
| | - Andrzej Dworak
- Centre of Polymer and Carbon Materials
- Polish Academy of Sciences
- 41-819 Zabrze
- Poland
| | - Wojciech Wałach
- Centre of Polymer and Carbon Materials
- Polish Academy of Sciences
- 41-819 Zabrze
- Poland
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16
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Daubian D, Gaitzsch J, Meier W. Synthesis and complex self-assembly of amphiphilic block copolymers with a branched hydrophobic poly(2-oxazoline) into multicompartment micelles, pseudo-vesicles and yolk/shell nanoparticles. Polym Chem 2020. [DOI: 10.1039/c9py01559k] [Citation(s) in RCA: 27] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
A new PEO-b-PEHOx amphiphilic diblock copolymer was achieved which unlocked new complex self-assembled structures. Thanks to its hydrophobic oxazoline block with a long branched side chain, EHOx, various potent structures were obtained.
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Affiliation(s)
- Davy Daubian
- Department of Physical Chemistry
- University of Basel
- 4058 Basel
- Switzerland
| | - Jens Gaitzsch
- Department of Physical Chemistry
- University of Basel
- 4058 Basel
- Switzerland
- Leibniz-Institut für Polymerforschung Dresden e.V
| | - Wolfgang Meier
- Department of Physical Chemistry
- University of Basel
- 4058 Basel
- Switzerland
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17
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Sedlacek O, Hoogenboom R. Drug Delivery Systems Based on Poly(2‐Oxazoline)s and Poly(2‐Oxazine)s. ADVANCED THERAPEUTICS 2019. [DOI: 10.1002/adtp.201900168] [Citation(s) in RCA: 50] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Affiliation(s)
- Ondrej Sedlacek
- Supramolecular Chemistry GroupCentre of Macromolecular Chemistry (CMaC)Department of Organic and Macromolecular ChemistryGhent University Krijgslaan 281 S4 B‐9000 Ghent Belgium
| | - Richard Hoogenboom
- Supramolecular Chemistry GroupCentre of Macromolecular Chemistry (CMaC)Department of Organic and Macromolecular ChemistryGhent University Krijgslaan 281 S4 B‐9000 Ghent Belgium
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18
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Lübtow MM, Lorson T, Finger T, Gröber‐Becker F, Luxenhofer R. Combining Ultra‐High Drug‐Loaded Micelles and Injectable Hydrogel Drug Depots for Prolonged Drug Release. MACROMOL CHEM PHYS 2019. [DOI: 10.1002/macp.201900341] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Affiliation(s)
- Michael M. Lübtow
- Functional Polymer Materials Chair for Advanced Materials Synthesis Department of Chemistry and Pharmacy and Bavarian Polymer Institute University of Würzburg Röntgenring 11 97070 Würzburg Germany
| | - Thomas Lorson
- Functional Polymer Materials Chair for Advanced Materials Synthesis Department of Chemistry and Pharmacy and Bavarian Polymer Institute University of Würzburg Röntgenring 11 97070 Würzburg Germany
| | - Tamara Finger
- Translational Center ‘Regenerative Therapies' (TLC‐RT) Fraunhofer Institute for Silicate Research (ISC) Neunerplatz 2 97082 Würzburg Germany
| | - Florian‐Kai Gröber‐Becker
- Translational Center ‘Regenerative Therapies' (TLC‐RT) Fraunhofer Institute for Silicate Research (ISC) Neunerplatz 2 97082 Würzburg Germany
- Chair of Tissue Engineering and Regenerative Medicine University Hospital Würzburg Röntgenring 11 97070 Würzburg Germany
| | - Robert Luxenhofer
- Functional Polymer Materials Chair for Advanced Materials Synthesis Department of Chemistry and Pharmacy and Bavarian Polymer Institute University of Würzburg Röntgenring 11 97070 Würzburg Germany
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19
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Pöppler AC, Lübtow MM, Schlauersbach J, Wiest J, Meinel L, Luxenhofer R. Loading-Dependent Structural Model of Polymeric Micelles Encapsulating Curcumin by Solid-State NMR Spectroscopy. Angew Chem Int Ed Engl 2019; 58:18540-18546. [PMID: 31529576 PMCID: PMC6916580 DOI: 10.1002/anie.201908914] [Citation(s) in RCA: 37] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2019] [Revised: 09/04/2019] [Indexed: 12/13/2022]
Abstract
Detailed insight into the internal structure of drug‐loaded polymeric micelles is scarce, but important for developing optimized delivery systems. We observed that an increase in the curcumin loading of triblock copolymers based on poly(2‐oxazolines) and poly(2‐oxazines) results in poorer dissolution properties. Using solid‐state NMR spectroscopy and complementary tools we propose a loading‐dependent structural model on the molecular level that provides an explanation for these pronounced differences. Changes in the chemical shifts and cross‐peaks in 2D NMR experiments give evidence for the involvement of the hydrophobic polymer block in the curcumin coordination at low loadings, while at higher loadings an increase in the interaction with the hydrophilic polymer blocks is observed. The involvement of the hydrophilic compartment may be critical for ultrahigh‐loaded polymer micelles and can help to rationalize specific polymer modifications to improve the performance of similar drug delivery systems.
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Affiliation(s)
- Ann-Christin Pöppler
- Institute of Organic Chemistry, University of Würzburg, Am Hubland, 97074, Würzburg, Germany
| | - Michael M Lübtow
- Lehrstuhl für Chemische Technologie der Materialsynthese, University of Würzburg, Röntgenring 11, 97070, Würzburg, Germany
| | - Jonas Schlauersbach
- Institute for Pharmacy and Food Chemistry, University of Würzburg, Am Hubland, 97074, Würzburg, Germany
| | - Johannes Wiest
- Institute for Pharmacy and Food Chemistry, University of Würzburg, Am Hubland, 97074, Würzburg, Germany
| | - Lorenz Meinel
- Institute for Pharmacy and Food Chemistry, University of Würzburg, Am Hubland, 97074, Würzburg, Germany
| | - Robert Luxenhofer
- Lehrstuhl für Chemische Technologie der Materialsynthese, University of Würzburg, Röntgenring 11, 97070, Würzburg, Germany
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20
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Pöppler A, Lübtow MM, Schlauersbach J, Wiest J, Meinel L, Luxenhofer R. Strukturmodell von Polymermizellen in Abhängigkeit von der Curcumin‐Beladung mithilfe von Festkörper‐NMR‐Spektroskopie. Angew Chem Int Ed Engl 2019. [DOI: 10.1002/ange.201908914] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Affiliation(s)
- Ann‐Christin Pöppler
- Institut für Organische ChemieJulius-Maximilians-Universität Würzburg Am Hubland 97074 Würzburg Deutschland
| | - Michael M. Lübtow
- Lehrstuhl für Chemische Technologie der MaterialsyntheseJulius-Maximilians-Universität Würzburg Röntgenring 11 97070 Würzburg Deutschland
| | - Jonas Schlauersbach
- Institut für Pharmazie und LebensmittelchemieJulius-Maximilians-Universität Würzburg Am Hubland 97074 Würzburg Deutschland
| | - Johannes Wiest
- Institut für Pharmazie und LebensmittelchemieJulius-Maximilians-Universität Würzburg Am Hubland 97074 Würzburg Deutschland
| | - Lorenz Meinel
- Institut für Pharmazie und LebensmittelchemieJulius-Maximilians-Universität Würzburg Am Hubland 97074 Würzburg Deutschland
| | - Robert Luxenhofer
- Lehrstuhl für Chemische Technologie der MaterialsyntheseJulius-Maximilians-Universität Würzburg Röntgenring 11 97070 Würzburg Deutschland
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21
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Kirila T, Smirnova A, Filippov A, Razina A, Tenkovtsev A, Filippov A. Thermosensitive star-shaped poly-2-ethyl-2-oxazine. Synthesis, structure characterization, conformation, and self-organization in aqueous solutions. Eur Polym J 2019. [DOI: 10.1016/j.eurpolymj.2019.109215] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023]
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22
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Haider MS, Schreiner J, Kendl S, Kroiss M, Luxenhofer R. A Micellar Mitotane Formulation with High Drug-Loading and Solubility: Physico-Chemical Characterization and Cytotoxicity Studies in 2D and 3D In Vitro Tumor Models. Macromol Biosci 2019; 20:e1900178. [PMID: 31596553 DOI: 10.1002/mabi.201900178] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2019] [Revised: 08/16/2019] [Indexed: 01/26/2023]
Abstract
Adrenocortical carcinoma (ACC) is a rare tumor and prognosis is overall poor but heterogeneous. Mitotane (MT) has been used for treatment of ACC for decades, either alone or in combination with cytotoxic chemotherapy. Even at doses up to 6 g per day, more than half of the patients do not achieve targeted plasma concentration (14-20 mg L-1 ) even after many months of treatment due to low water solubility, bioavailability, and unfavorable pharmacokinetic profile. Here a novel MT nanoformulation with very high MT concentrations in physiological aqueous media is reported. The MT-loaded nanoformulations are characterized by Fourier transform infrared spectroscopy, differential scanning calorimetry, and powder X-ray diffraction which confirms the amorphous nature of the drug. The polymer itself does not show any cytotoxicity in adrenal and liver cell lines. By using the ACC model cell line NCI-H295 both in monolayers and tumor cell spheroids, micellar MT is demonstrated to exhibit comparable efficacy to its ethanol solution. It is postulated that this formulation will be suitable for i.v. application and rapid attainment of therapeutic plasma concentrations. In conclusion, the micellar formulation is considered a promising tool to alleviate major drawbacks of current MT treatment while retaining bioactivity toward ACC in vitro.
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Affiliation(s)
- Malik Salman Haider
- Functional Polymer Materials, Chair for Chemical Technology of Material Synthesis, Faculty of Chemistry and Pharmacy, University of Würzburg and Bavarian Polymer Institute, Röntgenring 11, 97070, Würzburg, Germany
| | - Jochen Schreiner
- University Hospital Würzburg, Department of Internal Medicine I, Division of Endocrinology/Diabetology, Oberdürrbacher Str. 6, 97080, Würzburg, Germany
| | - Sabine Kendl
- University Hospital Würzburg, Department of Internal Medicine I, Division of Endocrinology/Diabetology, Oberdürrbacher Str. 6, 97080, Würzburg, Germany
| | - Matthias Kroiss
- University Hospital Würzburg, Department of Internal Medicine I, Division of Endocrinology/Diabetology, Oberdürrbacher Str. 6, 97080, Würzburg, Germany
| | - Robert Luxenhofer
- Functional Polymer Materials, Chair for Chemical Technology of Material Synthesis, Faculty of Chemistry and Pharmacy, University of Würzburg and Bavarian Polymer Institute, Röntgenring 11, 97070, Würzburg, Germany
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23
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Lübtow MM, Marciniak H, Schmiedel A, Roos M, Lambert C, Luxenhofer R. Ultra-High to Ultra-Low Drug-Loaded Micelles: Probing Host-Guest Interactions by Fluorescence Spectroscopy. Chemistry 2019; 25:12601-12610. [PMID: 31291028 PMCID: PMC6790594 DOI: 10.1002/chem.201902619] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2019] [Indexed: 12/13/2022]
Abstract
Polymer micelles are an attractive means to solubilize water insoluble compounds such as drugs. Drug loading, formulations stability and control over drug release are crucial factors for drug-loaded polymer micelles. The interactions between the polymeric host and the guest molecules are considered critical to control these factors but typically barely understood. Here, we compare two isomeric polymer micelles, one of which enables ultra-high curcumin loading exceeding 50 wt.%, while the other allows a drug loading of only 25 wt.%. In the low capacity micelles, steady-state fluorescence revealed a very unusual feature of curcumin fluorescence, a high energy emission at 510 nm. Time-resolved fluorescence upconversion showed that the fluorescence life time of the corresponding species is too short in the high-capacity micelles, preventing an observable emission in steady-state. Therefore, contrary to common perception, stronger interactions between host and guest can be detrimental to the drug loading in polymer micelles.
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Affiliation(s)
- Michael M. Lübtow
- Functional Polymer Materials, Chair for Advanced Materials SynthesisDepartment of Chemistry and Pharmacy and Bavarian Polymer InstituteUniversity of WürzburgRöntgenring 1197070WürzburgGermany
| | - Henning Marciniak
- Institute of Organic Chemistry and Center for Nanosystems ChemistryUniversity of WürzburgAm Hubland97070WürzburgGermany
| | - Alexander Schmiedel
- Institute of Organic Chemistry and Center for Nanosystems ChemistryUniversity of WürzburgAm Hubland97070WürzburgGermany
| | - Markus Roos
- Institute of Organic Chemistry and Center for Nanosystems ChemistryUniversity of WürzburgAm Hubland97070WürzburgGermany
| | - Christoph Lambert
- Institute of Organic Chemistry and Center for Nanosystems ChemistryUniversity of WürzburgAm Hubland97070WürzburgGermany
| | - Robert Luxenhofer
- Functional Polymer Materials, Chair for Advanced Materials SynthesisDepartment of Chemistry and Pharmacy and Bavarian Polymer InstituteUniversity of WürzburgRöntgenring 1197070WürzburgGermany
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24
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Hwang D, Ramsey JD, Makita N, Sachse C, Jordan R, Sokolsky-Papkov M, Kabanov AV. Novel poly(2-oxazoline) block copolymer with aromatic heterocyclic side chains as a drug delivery platform. J Control Release 2019; 307:261-271. [PMID: 31260756 PMCID: PMC7482421 DOI: 10.1016/j.jconrel.2019.06.037] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2019] [Revised: 06/22/2019] [Accepted: 06/26/2019] [Indexed: 10/26/2022]
Abstract
Here we report a novel poly(2-oxazoline)-based block copolymer with the aromatic heterocyclic side chains in one block, poly(2-methyl-2-oxazoline)-b-poly(2-N,N-dimethyl-1,3,5-triazine-2,4-diamine-6-ethyl-2-oxazoline) (PMeOx-PcBOx), and demonstrate its potential application as a drug delivery platform. The copolymer was synthesized via the condensation of N,N-dimethylbiguanide with the methyl ester side chain in poly(2-methoxycarboxyethyl-2-oxazoline) block (PMestOx) of the PMeOx-PMestOx diblock copolymer. We confirmed the N,N-dimethylbiguanide condensation with PMestOx and the complete conversion of the side chain to the N,N-dimethyl-1,3,5-triazine-2,4-diamine-6-ethyl moiety by NMR spectroscopy, MALDI-TOF mass spectroscopy, UV-Vis spectroscopy, and titration analysis. The PMeOx-PcBOx copolymer self-assemble into polymeric micelles in aqueous solution. Successful encapsulation into these micelles has been demonstrated for 1) several poorly soluble drugs, such as bruceantin and LY2109761, and 2) dichloro(1,2-diaminocyclohexane)platinum(II) (DachPt). The first class of drugs is incorporated possibly via hydrogen bonding and pi-pi interactions with the PcBOx side groups, while the second one is likely forms coordination bonds with the same side groups. The capability of this new copolymer to solubilize a uniquely diverse set of active pharmaceutical ingredients suggests potential applications in drug delivery.
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Affiliation(s)
- Duhyeong Hwang
- Center for Nanotechnology in Drug Delivery and Division of Pharmacoengineering and Molecular Pharmaceutics, Eshelman School of Pharmacy, University of North Carolina at Chapel Hill, NC 27599, USA
| | - Jacob D Ramsey
- Center for Nanotechnology in Drug Delivery and Division of Pharmacoengineering and Molecular Pharmaceutics, Eshelman School of Pharmacy, University of North Carolina at Chapel Hill, NC 27599, USA
| | - Naoki Makita
- Center for Nanotechnology in Drug Delivery and Division of Pharmacoengineering and Molecular Pharmaceutics, Eshelman School of Pharmacy, University of North Carolina at Chapel Hill, NC 27599, USA
| | - Clemens Sachse
- Department Chemie, Technische Universität Dresden, Zellescher Weg 19, 01069 Dresden, Germany
| | - Rainer Jordan
- Department Chemie, Technische Universität Dresden, Zellescher Weg 19, 01069 Dresden, Germany
| | - Marina Sokolsky-Papkov
- Center for Nanotechnology in Drug Delivery and Division of Pharmacoengineering and Molecular Pharmaceutics, Eshelman School of Pharmacy, University of North Carolina at Chapel Hill, NC 27599, USA
| | - Alexander V Kabanov
- Center for Nanotechnology in Drug Delivery and Division of Pharmacoengineering and Molecular Pharmaceutics, Eshelman School of Pharmacy, University of North Carolina at Chapel Hill, NC 27599, USA; Laboratory of Chemical Design of Bionanomaterials, Faculty of Chemistry, M.V. Lomonosov Moscow State University, Moscow 119992, Russia.
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25
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Lübtow MM, Mrlik M, Hahn L, Altmann A, Beudert M, Lühmann T, Luxenhofer R. Temperature-Dependent Rheological and Viscoelastic Investigation of a Poly(2-methyl-2-oxazoline)-b-poly(2- iso-butyl-2-oxazoline)-b-poly(2-methyl-2-oxazoline)-Based Thermogelling Hydrogel. J Funct Biomater 2019; 10:E36. [PMID: 31394886 PMCID: PMC6787588 DOI: 10.3390/jfb10030036] [Citation(s) in RCA: 23] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2019] [Revised: 07/01/2019] [Accepted: 07/30/2019] [Indexed: 12/13/2022] Open
Abstract
The synthesis and characterization of an ABA triblock copolymer based on hydrophilic poly(2-methyl-2-oxazoline) (pMeOx) blocks A and a modestly hydrophobic poly(2-iso-butyl-2-oxazoline) (piBuOx) block B is described. Aqueous polymer solutions were prepared at different concentrations (1-20 wt %) and their thermogelling capability using visual observation was investigated at different temperatures ranging from 5 to 80 °C. As only a 20 wt % solution was found to undergo thermogelation, this concentration was investigated in more detail regarding its temperature-dependent viscoelastic profile utilizing various modes (strain or temperature sweep). The prepared hydrogels from this particular ABA triblock copolymer have interesting rheological and viscoelastic properties, such as reversible thermogelling and shear thinning, and may be used as bioink, which was supported by its very low cytotoxicity and initial printing experiments using the hydrogels. However, the soft character and low yield stress of the gels do not allow real 3D printing at this point.
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Affiliation(s)
- Michael M Lübtow
- Polymer Functional Materials, Chair for Advanced Materials Synthesis, Department of Chemistry and Pharmacy and Bavarian Polymer Institute, Julius-Maximilians-University Würzburg, 97084 Würzburg, Germany
| | - Miroslav Mrlik
- Polymer Functional Materials, Chair for Advanced Materials Synthesis, Department of Chemistry and Pharmacy and Bavarian Polymer Institute, Julius-Maximilians-University Würzburg, 97084 Würzburg, Germany
- Centre of Polymer Systems, University Institute, Tomas Bata University in Zlin, Trida T. Bati 5678, 760 01 Zlin, Czech Republic
| | - Lukas Hahn
- Polymer Functional Materials, Chair for Advanced Materials Synthesis, Department of Chemistry and Pharmacy and Bavarian Polymer Institute, Julius-Maximilians-University Würzburg, 97084 Würzburg, Germany
| | - Alexander Altmann
- Polymer Functional Materials, Chair for Advanced Materials Synthesis, Department of Chemistry and Pharmacy and Bavarian Polymer Institute, Julius-Maximilians-University Würzburg, 97084 Würzburg, Germany
| | - Matthias Beudert
- Institute of Pharmacy and Food Chemistry, Julius-Maximilians-University Würzburg, Am Hubland, 97074 Würzburg, Germany
| | - Tessa Lühmann
- Institute of Pharmacy and Food Chemistry, Julius-Maximilians-University Würzburg, Am Hubland, 97074 Würzburg, Germany
| | - Robert Luxenhofer
- Polymer Functional Materials, Chair for Advanced Materials Synthesis, Department of Chemistry and Pharmacy and Bavarian Polymer Institute, Julius-Maximilians-University Würzburg, 97084 Würzburg, Germany.
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26
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Lübtow MM, Haider MS, Kirsch M, Klisch S, Luxenhofer R. Like Dissolves Like? A Comprehensive Evaluation of Partial Solubility Parameters to Predict Polymer-Drug Compatibility in Ultrahigh Drug-Loaded Polymer Micelles. Biomacromolecules 2019; 20:3041-3056. [PMID: 31318531 DOI: 10.1021/acs.biomac.9b00618] [Citation(s) in RCA: 61] [Impact Index Per Article: 12.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
Despite decades of research, our understanding of the molecular interactions between drugs and polymers in drug-loaded polymer micelles does not extend much beyond concepts such as "like-dissolves-like" or hydrophilic/hydrophobic. However, polymer-drug compatibility strongly affects formulation properties and therefore the translation of a formulation into the clinics. Specific interactions such as hydrogen-bonding, π-π stacking, or coordination interactions can be utilized to increase drug loading. This is commonly based on trial and error and eventually leads to an optimized drug carrier. Unfortunately, due to the unique characteristics of each drug, the deduction of advanced general concepts remains challenging. Furthermore, the introduction of complex moieties or specifically modified polymers hampers systematic investigations regarding polymer-drug compatibility as well as clinical translation. In this study, we reduced the complexity to isolate the crucial factors determining drug loading. Therefore, the compatibility of 18 different amphiphilic polymers for five different hydrophobic drugs was determined empirically. Subsequently, the obtained specificities were compared to theoretical compatibilities derived from either the Flory-Huggins interaction parameters or the Hansen solubility parameters. In general, the Flory-Huggins interaction parameters were less suited to correctly estimate the experimental drug solubilization compared to the Hansen solubility parameters. The latter were able to correctly predict some trend regarding good and poor solubilizers, yet the overall predictive strength of Hansen solubility parameters is clearly unsatisfactory.
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Affiliation(s)
- Michael M Lübtow
- Functional Polymer Materials, Chair for Advanced Materials Synthesis, Department of Chemistry and Pharmacy and Bavarian Polymer Institute , University of Würzburg , Röntgenring 11 , 97070 Würzburg , Germany
| | - Malik Salman Haider
- Functional Polymer Materials, Chair for Advanced Materials Synthesis, Department of Chemistry and Pharmacy and Bavarian Polymer Institute , University of Würzburg , Röntgenring 11 , 97070 Würzburg , Germany
| | - Marius Kirsch
- Functional Polymer Materials, Chair for Advanced Materials Synthesis, Department of Chemistry and Pharmacy and Bavarian Polymer Institute , University of Würzburg , Röntgenring 11 , 97070 Würzburg , Germany
| | - Stefanie Klisch
- Functional Polymer Materials, Chair for Advanced Materials Synthesis, Department of Chemistry and Pharmacy and Bavarian Polymer Institute , University of Würzburg , Röntgenring 11 , 97070 Würzburg , Germany
| | - Robert Luxenhofer
- Functional Polymer Materials, Chair for Advanced Materials Synthesis, Department of Chemistry and Pharmacy and Bavarian Polymer Institute , University of Würzburg , Röntgenring 11 , 97070 Würzburg , Germany
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Lübtow MM, Nelke LC, Seifert J, Kühnemundt J, Sahay G, Dandekar G, Nietzer SL, Luxenhofer R. Drug induced micellization into ultra-high capacity and stable curcumin nanoformulations: Physico-chemical characterization and evaluation in 2D and 3D in vitro models. J Control Release 2019; 303:162-180. [DOI: 10.1016/j.jconrel.2019.04.014] [Citation(s) in RCA: 42] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2019] [Revised: 04/04/2019] [Accepted: 04/10/2019] [Indexed: 01/02/2023]
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28
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Sedlacek O, Lava K, Verbraeken B, Kasmi S, De Geest BG, Hoogenboom R. Unexpected Reactivity Switch in the Statistical Copolymerization of 2-Oxazolines and 2-Oxazines Enabling the One-Step Synthesis of Amphiphilic Gradient Copolymers. J Am Chem Soc 2019; 141:9617-9622. [DOI: 10.1021/jacs.9b02607] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Ondrej Sedlacek
- Supramolecular Chemistry Group, Centre of Macromolecular Chemistry (CMaC), Department of Organic and Macromolecular Chemistry, Ghent University, Krijgslaan 281 S4, B-9000 Ghent, Belgium
| | - Kathleen Lava
- Supramolecular Chemistry Group, Centre of Macromolecular Chemistry (CMaC), Department of Organic and Macromolecular Chemistry, Ghent University, Krijgslaan 281 S4, B-9000 Ghent, Belgium
| | - Bart Verbraeken
- Supramolecular Chemistry Group, Centre of Macromolecular Chemistry (CMaC), Department of Organic and Macromolecular Chemistry, Ghent University, Krijgslaan 281 S4, B-9000 Ghent, Belgium
| | - Sabah Kasmi
- Department of Pharmaceutics, Ghent University, B-9000 Ghent, Belgium
| | - Bruno G. De Geest
- Department of Pharmaceutics, Ghent University, B-9000 Ghent, Belgium
| | - Richard Hoogenboom
- Supramolecular Chemistry Group, Centre of Macromolecular Chemistry (CMaC), Department of Organic and Macromolecular Chemistry, Ghent University, Krijgslaan 281 S4, B-9000 Ghent, Belgium
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