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Iliopoulou A, Iatridi Z, Tsitsilianis C. A Remarkable Impact of pH on the Thermo-Responsive Properties of Alginate-Based Composite Hydrogels Incorporating P2VP-PEO Micellar Nanoparticles. Polymers (Basel) 2024; 16:886. [PMID: 38611144 PMCID: PMC11013835 DOI: 10.3390/polym16070886] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2024] [Revised: 03/21/2024] [Accepted: 03/22/2024] [Indexed: 04/14/2024] Open
Abstract
A heterograft copolymer with an alginate backbone, hetero-grafted by polymer pendant chains displaying different lower critical solution temperatures (LCSTs), combined with a pH-responsive poly(2-vinyl pyridine)-b-poly(ethylene oxide) (P2VP-b-PEO) diblock copolymer forming micellar nanoparticles, was investigated in aqueous media at various pHs. Due to its thermo-responsive side chains, the copolymer forms hydrogels with a thermo-induced sol-gel transition, above a critical temperature, Tgel (thermo-thickening). However, by lowering the pH of the medium in an acidic regime, a remarkable increase in the elasticity of the formulation was observed. This effect was more pronounced in low temperatures (below Tgel), suggesting secondary physical crosslinking, which induces significant changes in the hydrogel thermo-responsiveness, transforming the sol-gel transition to soft gel-strong gel. Moreover, the onset of thermo-thickening shifted to lower temperatures followed by the broadening of the transition zone, implying intermolecular interactions between the uncharged alginate backbone with the PNIPAM side chains, likely through H-bonding. The shear-thinning behavior of the soft gel in low temperatures provides injectability, which allows potential applications for 3D printing. Furthermore, the heterograft copolymer/nanoparticles composite hydrogel, encapsulating a model hydrophobic drug in the hydrophobic cores of the nanoparticles, was evaluated as a pH-responsive drug delivery system. The presented tunable drug delivery system might be useful for biomedical potential applications.
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Saravanou SF, Tsitsilianis C, Pasparakis G. Harnessing the Interplay of Triple Cross-Linked Hydrogels toward Multiresponsive Alginate-Based Injectable Gels for 3D Printing Bioapplications. ACS Macro Lett 2023; 12:1614-1622. [PMID: 37956439 DOI: 10.1021/acsmacrolett.3c00470] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2023]
Abstract
We report on a single chain polymer gelator comprising an alginate backbone double grafted with thermoresponsive P(NIPAM86-co-NtBAM14)-NH2 polymer grafts and 3-aminophenylboronic acid moieties. The resulting polymer forms robust polymer networks resulting from three cooperative cross-linking mechanisms: (i) the hydrophobic association of the T-responsive polymer grafts above 24 °C, (ii) the formation of boronate esters between the boronic acid and the diols of the alginate backbone at physiological pH, and (iii) the ionic interactions of the residual carboxylate moieties with Ca2+ ions. The resulting material showed excellent tunability of the mechanical properties driven by stimuli combinations such as temperature, pH, or the addition of glucose as a network disruptor covering a storage modulus range from ∼260 Pa up to ∼1390 Pa by selective stimuli combinations. Also, the material was found to be nontoxic and could form arbitrary structures via 3D printing that can undergo multi-stimuli-responsive erosion profiles.
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Affiliation(s)
| | | | - George Pasparakis
- Department of Chemical Engineering, University of Patras, 26500 Patras, Greece
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3
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Kargaki ME, Arfara F, Iatrou H, Tsitsilianis C. pH-Sensitive Poly(acrylic acid)-g-poly(L-lysine) Charge-Driven Self-Assembling Hydrogels with 3D-Printability and Self-Healing Properties. Gels 2023; 9:512. [PMID: 37504391 PMCID: PMC10379232 DOI: 10.3390/gels9070512] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2023] [Revised: 06/21/2023] [Accepted: 06/22/2023] [Indexed: 07/29/2023] Open
Abstract
We report the rheological behavior of aqueous solutions of a graft copolymer polyampholyte, constituted of polyacrylic acid (PAA) backbone grafted by Poly(L-lysine) (PAA-b-PLL). The graft copolymer self-assembles in aqueous media, forming a three-dimensional (3D) network through polyelectrolyte complexation of the oppositely charged PAA and PLL segments. Rheological investigations showed that the hydrogel exhibits interesting properties, namely, relatively low critical gel concentration, elastic response with slow dynamics, remarkable extended critical strain to flow, shear responsiveness, injectability, 3D printability and self-healing. Due to the weak nature of the involved polyelectrolyte segments, the hydrogel properties display pH-dependency, and they are affected by the presence of salt. Especially upon varying pH, the PLL secondary structure changes from random coil to α-helix, affecting the crosslinking structural mode and, in turn, the overall network structure as reflected in the rheological properties. Thanks to the biocompatibility of the copolymer constituents and the biodegradability of PLL, the designed gelator seems to exhibit potential for bioapplications.
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Affiliation(s)
- Maria-Eleni Kargaki
- Department of Chemical Engineering, University of Patras, 26500 Patras, Greece
| | - Foteini Arfara
- Department of Chemistry, University of Athens, Panepistimiopolis, Zografou, 15771 Athens, Greece
| | - Hermis Iatrou
- Department of Chemistry, University of Athens, Panepistimiopolis, Zografou, 15771 Athens, Greece
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Saravanou SF, Ioannidis K, Dimopoulos A, Paxinou A, Kounelaki F, Varsami SM, Tsitsilianis C, Papantoniou I, Pasparakis G. Dually crosslinked injectable alginate-based graft copolymer thermoresponsive hydrogels as 3D printing bioinks for cell spheroid growth and release. Carbohydr Polym 2023; 312:120790. [PMID: 37059530 DOI: 10.1016/j.carbpol.2023.120790] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2022] [Revised: 03/01/2023] [Accepted: 03/05/2023] [Indexed: 03/12/2023]
Abstract
In this work a dual crosslinked network based on sodium alginate graft copolymer, bearing poly(N-isopropylacrylamide-co-N-tert-butylacrylamide) P(NIPAM-co-NtBAM) side chains was developed and examined as a shear thinning soft gelating bioink. The copolymer was found to undergo a two-step gelation mechanism; in the first step a three-dimensional (3D) network is formed through ionic interactions between the negatively ionized carboxylic groups of the alginate backbone and the positive charges of Ca2+ divalent cations, according to the "egg-box" mechanism. The second gelation step occurs upon heating which triggers the hydrophobic association of the thermoresponsive P(NIPAM-co-NtBAM) side chains, increasing the network crosslinking density in a highly cooperative manner. Interestingly, the dual crosslinking mechanism resulted in a five-to-eight-fold improvement of the storage modulus implying reinforced hydrophobic crosslinking above the critical thermo-gelation temperature which is further boosted by the ionic crosslinking of the alginate backbone. The proposed bioink could form arbitrary geometries under mild 3D printing conditions. Last, it is demonstrated that the proposed developed bioink can be further utilized as bioprinting ink and showcased its ability to promote human periosteum derived cells (hPDCs) growth in 3D and their capacity to form 3D spheroids. In conclusion, the bioink, owing its ability to reverse thermally the crosslinking of its polymer network, can be further utilized for the facile recovery of the cell spheroids, implying its promising potential use as cell spheroid-forming template bionk for applications in 3D biofabrication.
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Popescu MT, Tsitsilianis C. Gold/Pentablock Terpolymer Hybrid Multifunctional Nanocarriers for Controlled Delivery of Tamoxifen: Effect of Nanostructure on Release Kinetics. Molecules 2022; 27:molecules27123764. [PMID: 35744890 PMCID: PMC9231331 DOI: 10.3390/molecules27123764] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/17/2022] [Revised: 06/07/2022] [Accepted: 06/08/2022] [Indexed: 11/16/2022]
Abstract
Here, we describe the preparation and characterization of organic/inorganic hybrid polymer multifunctional nanocarriers. Novel nanocomposites of gold nanoparticles using pH-responsive coordination pentablock terpolymers of poly(ε-caprolactone)-b-poly(ethylene oxide)-b-poly(2-vinylpyridine)-b-poly(ethylene oxide)-b-poly(ε-caprolactone), bearing or not bearing partially quaternized vinylpyridine moieties, were studied. The template morphology of the coordination pentablock terpolymer at physiological pH ranges from crew-cut to multicompartmentalized micelles which can be tuned by chemical modification of the central block. Additionally, the presence of 2VP groups allows the coordination of gold ions, which can be reduced in situ to construct gold@polymer nanohybrids. Furthermore, the possibility of tuning the gold distribution in the micelles, through partial quaternization of the central P2VP block, was also investigated. Various morphological gold colloidal nanoparticles such as gold@core-corona nanoparticles and gold@core-gold@corona nanoparticles were synthesized on the corresponding template of the pentablock terpolymer, first by coordination with gold ions, followed by reduction with NaBH4. The pentablock and gold@pentablock nanoparticles could sparingly accommodate a water-soluble drug, Tamoxifen (TAX), in their hydrophobic micellar cores. The nanostructure of the nanocarrier remarkably affects the TAX delivery kinetics. Importantly, the hybrid gold@polymer nanoparticles showed prolonged release profiles for the guest molecule, relative to the corresponding bare amphiphilic pentablock polymeric micelles. These Gold@pentablock terpolymer hybrid nanoparticles could act as a multifunctional theranostic nanoplatform, integrating sustainable pH-controlled drug delivery, diagnostic function and photothermal therapy.
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Stamou A, Iatrou H, Tsitsilianis C. NIPAm-Based Modification of Poly(L-lysine): A pH-Dependent LCST-Type Thermo-Responsive Biodegradable Polymer. Polymers (Basel) 2022; 14:polym14040802. [PMID: 35215715 PMCID: PMC8962975 DOI: 10.3390/polym14040802] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2022] [Revised: 02/15/2022] [Accepted: 02/16/2022] [Indexed: 11/16/2022] Open
Abstract
Polylysine is a biocompatible, biodegradable, water soluble polypeptide. Thanks to the pendant primary amines it bears, it is susceptible to modification reactions. In this work Poly(L-lysine) (PLL) was partially modified via the effortless free-catalysed aza-Michael addition reaction at room temperature by grafting N-isopropylacrylamide (NIPAm) moieties onto the amines. The resulting PLL-g-NIPAm exhibited LCST-type thermosensitivity. The LCST can be tuned by the NIPAm content incorporated in the macromolecules. Importantly, depending on the NIPAm content, LCST is highly dependent on pH and ionic strength due to ionization capability of the remaining free lysine residues. PLL-g-NIPAm constitutes a novel biodegradable LCST polymer that could be used as “smart” block in block copolymers and/or terpolymers, of any macromolecular architecture, to design pH/Temperature-responsive self-assemblies (nanocarriers and/or networks) for potential bio-applications.
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Affiliation(s)
- Aggeliki Stamou
- Department of Chemical Engineering, University of Patras, 26500 Patras, Greece;
| | - Hermis Iatrou
- Department of Chemistry, University of Athens, Panepistimiopolis, Zografou, 15771 Athens, Greece;
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Saravanou SF, Iatridi Z, Tsitsilianis C. Corrigendum to "Injectable self-assembling hydrogel from alginate grafted by P(N-isopropylacrylamide-co-N-tert-butylacrylamide) random copolymers" [Carbohydr. Polym. 219 (2019) 344-352]. Carbohydr Polym 2021; 262:117931. [PMID: 33838809 DOI: 10.1016/j.carbpol.2021.117931] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Affiliation(s)
| | - Zacharoula Iatridi
- Department of Chemical Engineering, University of Patras, 26500, Patras, Greece
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Theodorakis N, Saravanou SF, Kouli NP, Iatridi Z, Tsitsilianis C. pH/Thermo-Responsive Grafted Alginate-Based SiO 2 Hybrid Nanocarrier/Hydrogel Drug Delivery Systems. Polymers (Basel) 2021; 13:1228. [PMID: 33920243 PMCID: PMC8069398 DOI: 10.3390/polym13081228] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2021] [Revised: 04/08/2021] [Accepted: 04/09/2021] [Indexed: 12/27/2022] Open
Abstract
We report the preparation of mesoporous silica nanoparticles covered by layer by layer (LbL) oppositely charged weak polyelectrolytes, comprising poly(allylamine hydrochloride) (PAH) and a sodium alginate, highly grafted by N-isopropylacrylamide/N-tert-butylacrylamide random copolymers, NaALG-g-P(NIPAM90-co-NtBAM10) (NaALG-g). Thanks to the pH dependence of the degree of ionization of the polyelectrolytes and the LCST-type thermosensitivity of the grafting chains of the NaALG-g, the as-prepared hybrid nanoparticles (hNP) exhibit pH/thermo-responsive drug delivery capabilities. The release kinetics of rhodamine B (RB, model drug) can be controlled by the number of PAH/NaALG-g bilayers and more importantly by the environmental conditions, namely, pH and temperature. As observed, the increase of pH and/or temperature accelerates the RB release under sink conditions. The same NaALG-g was used as gelator to fabricate a hNP@NaALG-g hydrogel composite. This formulation forms a viscous solution at room temperature, and it is transformed to a self-assembling hydrogel (sol-gel transition) upon heating at physiological temperature provided that its Tgel was regulated at 30.7 °C, by the NtBAM hydrophobic monomer incorporation in the side chains. It exhibits excellent injectability thanks to its combined thermo- and shear-responsiveness. The hNP@NaALG-g hydrogel composite, encapsulating hNP covered with one bilayer, exhibited pH-responsive sustainable drug delivery. The presented highly tunable drug delivery system (DDS) (hNP and/or composite hydrogel) might be useful for biomedical potential applications.
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Affiliation(s)
| | | | | | - Zacharoula Iatridi
- Department of Chemical Engineering, University of Patras, 26500 Patras, Greece; (N.T.); (S.-F.S.); (N.-P.K.)
| | - Constantinos Tsitsilianis
- Department of Chemical Engineering, University of Patras, 26500 Patras, Greece; (N.T.); (S.-F.S.); (N.-P.K.)
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Safakas K, Saravanou SF, Iatridi Z, Tsitsilianis C. Alginate- g-PNIPAM-Based Thermo/Shear-Responsive Injectable Hydrogels: Tailoring the Rheological Properties by Adjusting the LCST of the Grafting Chains. Int J Mol Sci 2021; 22:3824. [PMID: 33917134 PMCID: PMC8067843 DOI: 10.3390/ijms22083824] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2021] [Revised: 04/04/2021] [Accepted: 04/05/2021] [Indexed: 12/14/2022] Open
Abstract
Graft copolymers of alginate backbone and N-isopropylacrylamide/N-tert-butylacrylamide random copolymer, P(NIPAMx-co-NtBAMy), side chains (stickers) with various NtBAM content were designed and explored in aqueous media. Self-assembling thermoresponsive hydrogels are formed upon heating, in all cases, through the hydrophobic association of the P(NIPAMx-co-NtBAMy) sticky pendant chains. The rheological properties of the formulations depend remarkably on the NtBAM hydrophobic content, which regulates the lower critical solution temperature (LCST) and, in turn, the stickers' thermo-responsiveness. The gelation point, Tgel, was shifted to lower temperatures from 38 to 20 °C by enriching the PNIPAM chains with 20 mol % NtBAM, shifting accordingly to the gelation temperature window. The consequences of the Tgel shift to the hydrogels' rheological properties are significant at room and body temperature. For instance, at 37 °C, the storage modulus increases about two orders of magnitude and the terminal relaxation time increase about 10 orders of magnitude by enriching the stickers with 20 mol % hydrophobic moieties. Two main thermo-induced behaviors were revealed, characterized by a sol-gel and a weak gel-stiff gel transition for the copolymer with stickers of low (0.6 mol %) and high (14, 20 mol %) NtBAM content, respectively. The first type of hydrogels is easily injectable, while for the second one, the injectability is provided by shear-thinning effects. The influence of the type of media (phosphate buffer (PB), phosphate-buffered saline (PBS), Dulbecco's modified Eagle's medium (DMEM)) on the hydrogel properties was also explored and discussed. The 4 wt % NaALG-g-P(NIPAM80-co-NtBAM20)/DMEM formulation showed excellent shear-induced injectability at room temperature and instantaneous thermo-induced gel stiffening at body temperature, rendering it a good candidate for cell transplantation potential applications.
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Affiliation(s)
| | | | | | - Constantinos Tsitsilianis
- Department of Chemical Engineering, University of Patras, 26500 Patras, Greece; (K.S.); (S.-F.S.); (Z.I.)
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10
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Dyakonova MA, Li Y, Besiri IN, Di Z, Grillo I, Tsitsilianis C, Papadakis CM. Effect of cosolvent on the rheological properties and self-assembled structures from telechelic polyampholytes. Colloid Polym Sci 2021. [DOI: 10.1007/s00396-020-04758-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
Abstract
AbstractA triblock copolymer with hydrophobic end blocks and a polyampholytic middle block is investigated in a mixture of water and acetone with a focus on the dependence of the rheological properties and of the micellar structure and correlation on the content of acetone. The polymer under study is PMMA86-b-P(DEA190-co-MAA96)-b-PMMA86, where PMMA stands for poly(methyl methacrylate) and P(DEA-co-MAA) for poly(2-(diethylamino) ethyl methacrylate-co-methacrylic acid). The pH is chosen at 3. Rheological measurements reveal a transition from a viscoelastic solid over a viscoelastic liquid to a freely flowing liquid upon addition of 5 or 10 wt% of acetone to a 3 wt% aqueous polymer solution, respectively. Using small-angle neutron scattering on 0.5 wt% polymer solutions in water/acetone with the content of the latter ranging between 0 and 30 wt%, significant structural changes are observed as well, such as a decrease of the distance between the PMMA cross-links and of the size of the network clusters upon increasing acetone constant. These changes are attributed to the reduction of the dielectric constant by the addition of the cosolvent acetone, enhancing the flexibility of the middle blocks and their tendency to backfolding, as well as to the decrease of the solvent selectivity, inducing significant exchange rate enhancement of the core-forming PMMA blocks.
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Jung FA, Posselt D, Smilgies DM, Panteli PA, Tsitsilianis C, Patrickios CS, Papadakis CM. Charge-Dependent Microphase Separation in Thin Films from a Multiresponsive Pentablock Quaterpolymer: A GISAXS Investigation. Macromolecules 2020. [DOI: 10.1021/acs.macromol.0c01151] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Florian A. Jung
- Fachgebiet Physik weicher Materie, Physik-Department, Technische Universität München, James-Franck-Str. 1, 85748 Garching, Germany
| | - Dorthe Posselt
- IMFUFA, Department of Science and Environment, Roskilde University, P.O. Box 260, 4000 Roskilde, Denmark
| | - Detlef-M. Smilgies
- Cornell High Energy Synchrotron Source, Cornell University, Ithaca, New York 14850, United States
| | - Panayiota A. Panteli
- Department of Chemistry, University of Cyprus, P.O. Box 20537, 1678 Nicosia, Cyprus
| | | | - Costas S. Patrickios
- Department of Chemistry, University of Cyprus, P.O. Box 20537, 1678 Nicosia, Cyprus
| | - Christine M. Papadakis
- Fachgebiet Physik weicher Materie, Physik-Department, Technische Universität München, James-Franck-Str. 1, 85748 Garching, Germany
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12
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Iatridi Z, Evangelatou K, Theodorakis N, Angelopoulou A, Avgoustakis K, Tsitsilianis C. Multicompartmental Mesoporous Silica/Polymer Nanostructured Hybrids: Design Capabilities by Integrating Linear and Star-Shaped Block Copolymers. Polymers (Basel) 2019; 12:E51. [PMID: 31906238 PMCID: PMC7023666 DOI: 10.3390/polym12010051] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2019] [Revised: 12/20/2019] [Accepted: 12/22/2019] [Indexed: 12/13/2022] Open
Abstract
Poly(2-vinyl pyridine)-b-poly(ethylene oxide) (P2VP-b-PEO) linear diblock copolymer and polystyrene-poly(ethylene oxide) (PS10PEO10) heteroarm star copolymer were used as building elements to prepare organic-inorganic hybrids. By using the layer-by-layer (LbL) methodology, these elements were integrated on mesoporous silica through non-covalent interactions, namely, ionic and H-bonding. For the latter, tannic acid (TA) was used as an intermediate layer. The deposition of the various layers was monitored by thermogravimetric analysis (TGA), electrophoretic measurements, and confocal microscopy. The final silica hybrid, bearing alternating P2VP-b-PEO and PS10PEO10 star layers was capable of carrying one hydrophilic and two hydrophobic chemical species in distinct compartments. These multicompartmental organic-inorganic hybrids could be used as nanostructured carriers for pH-responsive multiple drug delivery and potential theranostic applications.
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Affiliation(s)
- Zacharoula Iatridi
- Department of Chemical Engineering, University of Patras, 26504 Patras, Greece; (Z.I.); (K.E.); (N.T.)
| | - Kyriaki Evangelatou
- Department of Chemical Engineering, University of Patras, 26504 Patras, Greece; (Z.I.); (K.E.); (N.T.)
| | - Nikolaos Theodorakis
- Department of Chemical Engineering, University of Patras, 26504 Patras, Greece; (Z.I.); (K.E.); (N.T.)
| | - Athina Angelopoulou
- Department of Pharmacy, Medical School, University of Patras, 26504 Patras, Greece; (A.A.); (K.A.)
| | - Konstantinos Avgoustakis
- Department of Pharmacy, Medical School, University of Patras, 26504 Patras, Greece; (A.A.); (K.A.)
| | - Constantinos Tsitsilianis
- Department of Chemical Engineering, University of Patras, 26504 Patras, Greece; (Z.I.); (K.E.); (N.T.)
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Jung FA, Panteli PA, Ko CH, Kang JJ, Barnsley LC, Tsitsilianis C, Patrickios CS, Papadakis CM. Structural Properties of Micelles Formed by Telechelic Pentablock Quaterpolymers with pH-Responsive Midblocks and Thermoresponsive End Blocks in Aqueous Solution. Macromolecules 2019. [DOI: 10.1021/acs.macromol.9b01775] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Affiliation(s)
- Florian A. Jung
- Fachgebiet Physik weicher Materie, Physik-Department, Technische Universität München, James-Franck Str. 1, 85748 Garching, Germany
| | - Panayiota A. Panteli
- Department of Chemistry, University of Cyprus, P. O. Box 20537, 1678 Nicosia, Cyprus
| | - Chia-Hsin Ko
- Fachgebiet Physik weicher Materie, Physik-Department, Technische Universität München, James-Franck Str. 1, 85748 Garching, Germany
| | - Jia-Jhen Kang
- Fachgebiet Physik weicher Materie, Physik-Department, Technische Universität München, James-Franck Str. 1, 85748 Garching, Germany
| | - Lester C. Barnsley
- Jülich Centre for Neutron Science (JCNS) at Heinz Maier-Leibnitz Zentrum (MLZ), Forschungszentrum Jülich GmbH, Lichtenbergstr. 1, 85748 Garching, Germany
| | | | - Costas S. Patrickios
- Department of Chemistry, University of Cyprus, P. O. Box 20537, 1678 Nicosia, Cyprus
| | - Christine M. Papadakis
- Fachgebiet Physik weicher Materie, Physik-Department, Technische Universität München, James-Franck Str. 1, 85748 Garching, Germany
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14
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Ntaikou I, Koumelis I, Kamilari M, Iatridi Z, Tsitsilianis C, Lyberatos G. Effect of nitrogen limitation on polyhydroxyalkanoates production efficiency, properties and microbial dynamics using a soil-derived mixed continuous culture. International Journal of Biobased Plastics 2019. [DOI: 10.1080/24759651.2019.1648016] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
Affiliation(s)
- Ioanna Ntaikou
- Institute of Chemical Engineering Sciences, Foundation for Research and Technology (ICEHT/FORTH), Patras, Greece
| | - Ioannis Koumelis
- Institute of Chemical Engineering Sciences, Foundation for Research and Technology (ICEHT/FORTH), Patras, Greece
- Department of Chemical Engineering, University of Patras, Patras, Greece
| | - Maria Kamilari
- Department of Biology, University of Patras, Patras, Greece
- Department of Biology, Section of Ecology and Evolution, University of Copenhagen, Copenhagen, Denmark
| | - Zacharoula Iatridi
- Department of Chemical Engineering, University of Patras, Patras, Greece
| | | | - Gerasimos Lyberatos
- Institute of Chemical Engineering Sciences, Foundation for Research and Technology (ICEHT/FORTH), Patras, Greece
- School of Chemical Engineering, National Technical University of Athens, Athens, Greece
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15
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Iatridi Z, Saravanou SF, Tsitsilianis C. Injectable self-assembling hydrogel from alginate grafted by P(N-isopropylacrylamide-co-N-tert-butylacrylamide) random copolymers. Carbohydr Polym 2019; 219:344-352. [PMID: 31151534 DOI: 10.1016/j.carbpol.2019.05.045] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2019] [Revised: 04/25/2019] [Accepted: 05/13/2019] [Indexed: 12/21/2022]
Abstract
Sodium alginate grafted by a thermo-responsive copolymer of N-isopropylacrylamide, enriched with the hydrophobic N-tert-butylacrylamide monomer, (P(NIPAM-co-NtBAM)-NH2) was synthesized and its thermo- and shear-induced responsive capabilities were studied through rheology. The graft copolymer formed a 3D network through thermo-induced hydrophobic association of the thermo-responsive P(NIPAM-co-NtBAM) side chains in water. By applying the frequency-temperature superposition principle, the terminal relaxation time, τ and the shear viscosity, as a function of temperature were evaluated. Both parameters increased exponentially upon heating orders of magnitude, 15 °C above the onset of gelation (35 °C). It is shown that the thermo-induced thickening effect was mainly due to the slowdown of the P(NIPAM90-co-NtBAM10) associative side chains exchange dynamics. Moreover, combination of shear- and thermo-responsiveness provided excellent hydrogel injectability with instantaneous gelation at physiological temperature. The better insight of the thermo-thickening mechanism through oscillatory rheology allows precise tuning of the carbohydrate-based hydrogel properties towards potential bioapplications.
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Affiliation(s)
- Zacharoula Iatridi
- Department of Chemical Engineering, University of Patras, 26500 Patras, Greece
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16
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Gkermpoura SS, Papadimitriou KD, Skountzos EN, Polyzos I, Pastore Carbone MG, Kotrotsos A, Mavrantzas VG, Galiotis C, Tsitsilianis C. 3-Arm star pyrene-functional PMMAs for efficient exfoliation of graphite in chloroform: fabrication of graphene-reinforced fibrous veils. Nanoscale 2019; 11:915-931. [PMID: 30298899 DOI: 10.1039/c8nr06888g] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
3-Arm PMMAs end-functionalized by pyrene were designed as dispersing/stabilizing agents for the liquid-phase exfoliation of graphite in low-boiling point solvents like chloroform. The synthetic procedure comprised ARGET ATRP controlled polymerization, click chemistry and the quaternization reaction of triazole, ensuring tailor-made, well-defined pyrene-functional star PMMAs. Among a series of different pyrene-functional macromolecular topologies, the (PMMA-py2)3 proved the most efficient exfoliation agent giving relatively high graphene concentration (0.36 mg ml-1) at exceptionally low polymer/graphite mass ratio (mP/mGF = 0.003) and short sonication time (3 h). A 5-cycle iterative procedure relying on the redispersion of the sediment was developed yielding CG = 1.29 mg ml-1 with 14.8% exfoliation yield, under the favorable conditions of 10.5 h total shear mixing/tip sonication time and overall mP/mGF ratio as low as 0.15. In parallel, all-atom molecular dynamics simulations were conducted which helped understand the mechanism by which pyrene-functional macromolecular topologies act as efficient dispersing agents of graphene. Finally the G@(PMMA-Py)3 hybrids were well dispersed into the PMMA matrix by electrospinning to fabricate graphene-based nanocomposite fibrous veils. These graphene/polymer nanocomposites exhibited enhanced stiffness and strength by a factor of 4.4 with 1.5 wt% graphene hybrids as nanofillers.
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Affiliation(s)
- Sandra S Gkermpoura
- Department of Chemical Engineering, Universty of Patras, GR - 26504, Patras, Greece.
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17
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Iatridi Z, Angelopoulou A, Voulgari E, Avgoustakis K, Tsitsilianis C. Star-Graft Quarterpolymer-Based Polymersomes as Nanocarriers for Co-Delivery of Hydrophilic/Hydrophobic Chemotherapeutic Agents. ACS Omega 2018; 3:11896-11908. [PMID: 30320280 PMCID: PMC6173558 DOI: 10.1021/acsomega.8b01437] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 06/25/2018] [Accepted: 09/11/2018] [Indexed: 06/08/2023]
Abstract
We report the fabrication of polymersomes, using as building blocks star-graft quarterpolymers, composed of hydrophobic polystyrene and pH-sensitive poly(2-vinylpyridine)-b-poly(acrylic acid) (P2VP-b-PAA) arms, emanated from a common nodule, enriched by thermosensitive poly(N-isopropylacrylamide) grafts covalently bonded on the PAA block-arms. These multicompartmental polymersomes were evaluated as nanocarriers for the encapsulation and controlled co-delivery of doxorubicin (hydrophilic) and paclitaxel (hydrophobic) chemotherapeutic agents. The polymersomes can load these drugs in different compartments and can efficiently be internalized in the human lung adenocarcinoma epithelial cells, delivering their cargo and inducing high cell apoptosis. The release kinetics of both anticancer agents was controlled differently by the environmental conditions (pH and temperature). Enhanced release was observed at the acidic pH 6.0 and under physiological temperature (37 °C). At the same total drug level, co-delivery of these drugs with the polymersomes caused enhanced cytotoxicity and induced significantly higher cell apoptosis in the cancer cell line compared to the polymersomes loaded with either of the two drugs.
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Affiliation(s)
- Zacharoula Iatridi
- Department
of Chemical Engineering and Department of Pharmacy, Medical
School, University of Patras, 26500 Patras, Greece
| | - Athina Angelopoulou
- Department
of Chemical Engineering and Department of Pharmacy, Medical
School, University of Patras, 26500 Patras, Greece
| | - Efstathia Voulgari
- Department
of Chemical Engineering and Department of Pharmacy, Medical
School, University of Patras, 26500 Patras, Greece
| | - Konstantinos Avgoustakis
- Department
of Chemical Engineering and Department of Pharmacy, Medical
School, University of Patras, 26500 Patras, Greece
- Biomedical
Research Foundation of Academy of Athens (BRFAA), Athens 11527, Greece
| | - Constantinos Tsitsilianis
- Department
of Chemical Engineering and Department of Pharmacy, Medical
School, University of Patras, 26500 Patras, Greece
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18
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Erwin AJ, Korolovych VF, Iatridi Z, Tsitsilianis C, Ankner JF, Tsukruk VV. Tunable Compartmentalized Morphologies of Multilayered Dual Responsive Star Block Polyampholytes. Macromolecules 2018. [DOI: 10.1021/acs.macromol.8b00744] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Affiliation(s)
- Andrew J. Erwin
- School of Materials Science and Engineering, Georgia Institute of Technology, Atlanta, Georgia 30332, United States
| | - Volodymyr F. Korolovych
- School of Materials Science and Engineering, Georgia Institute of Technology, Atlanta, Georgia 30332, United States
| | - Zacharoula Iatridi
- Department of Chemical Engineering, University of Patras, 26504 Patras, Greece
| | | | - John F. Ankner
- Spallation Neutron Source, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, United States
| | - Vladimir V. Tsukruk
- School of Materials Science and Engineering, Georgia Institute of Technology, Atlanta, Georgia 30332, United States
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19
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Ntaikou I, Koumelis I, Tsitsilianis C, Parthenios J, Lyberatos G. Comparison of yields and properties of microbial polyhydroxyalkanoates generated from waste glycerol based substrates. Int J Biol Macromol 2018; 112:273-283. [DOI: 10.1016/j.ijbiomac.2018.01.175] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2017] [Revised: 01/22/2018] [Accepted: 01/26/2018] [Indexed: 12/22/2022]
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20
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Liaskoni A, Angelopoulou A, Voulgari E, Popescu MT, Tsitsilianis C, Avgoustakis K. Paclitaxel controlled delivery using a pH-responsive functional-AuNP/block-copolymer vesicular nanocarrier composite system. Eur J Pharm Sci 2018; 117:177-186. [PMID: 29477643 DOI: 10.1016/j.ejps.2018.02.021] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2017] [Revised: 02/08/2018] [Accepted: 02/20/2018] [Indexed: 10/17/2022]
Abstract
Paclitaxel (PTX)-loaded gold nanoparticles functionalized with mercaptooctanoic acid (MOA) and folic acid (FA) (AuMOA-FA) were encapsulated within pH-sensitive poly(2-vinylpyridine)-b-poly(ethylene oxide) (P2VP-PEO) vesicles with the aim to develop a more selective injectable nano-formulation for PTX, lacking the side effects of the conventional PTX delivery system. The size of the resulting composite vesicles was lower than 200 nm, i.e. it is suitable for tumor targeting applications taking advantage of the enhanced permeability and retention (EPR) effect. The vesicles did not aggregate in the presence of high electrolyte concentrations, indicating the colloidal stability of the vesicles. The vesicles did not leak their AuMOA-FA or PTX content at physiological pH of 7.4. However, AuMOA-FA and PTX release were significantly accelerated at acidic pHs resembling tumor environment and acidic intracellular compartments. PTX release from the vesicles at acidic pH apparently follows AuMOA-FA release from the vesicles. Flow cytometry measurements and confocal laser scanning microscopy images showed that the vesicles could enter A549 cancer cells in culture and that cellular uptake increased with time. Blank vesicles did not exhibit cytotoxicity and did not induce apoptosis in A549 cancer cells. The PTX currying vesicles exhibited comparable or a little higher cytotoxicity than free PTX. Both the PTX currying vesicles and free PTX induced A549 cells apoptosis, however the vesicle-encapsulated PTX induced a higher percentage of late apoptotic cells than free PTX.
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Affiliation(s)
- Athina Liaskoni
- Laboratory of Pharmaceutical Technology, Department of Pharmacy, University of Patras, 26504 Patras, Greece
| | - Athina Angelopoulou
- Laboratory of Pharmaceutical Technology, Department of Pharmacy, University of Patras, 26504 Patras, Greece
| | - Efstathia Voulgari
- Laboratory of Pharmaceutical Technology, Department of Pharmacy, University of Patras, 26504 Patras, Greece
| | | | | | - Konstantinos Avgoustakis
- Laboratory of Pharmaceutical Technology, Department of Pharmacy, University of Patras, 26504 Patras, Greece.
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21
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Tsitsilianis C, Serras G, Ko CH, Jung F, Papadakis CM, Rikkou-Kalourkoti M, Patrickios CS, Schweins R, Chassenieux C. Thermoresponsive Hydrogels Based on Telechelic Polyelectrolytes: From Dynamic to “Frozen” Networks. Macromolecules 2018. [DOI: 10.1021/acs.macromol.8b00193] [Citation(s) in RCA: 33] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Affiliation(s)
| | - George Serras
- Department of Chemical Engineering, University of Patras, 26504 Patras, Greece
| | - Chia-Hsin Ko
- Physik-Department, Physik weicher Materie, Technische Universität München, James-Franck Str. 1, 85748, Garching, Germany
| | - Florian Jung
- Physik-Department, Physik weicher Materie, Technische Universität München, James-Franck Str. 1, 85748, Garching, Germany
| | - Christine M. Papadakis
- Physik-Department, Physik weicher Materie, Technische Universität München, James-Franck Str. 1, 85748, Garching, Germany
| | | | - Costas S. Patrickios
- Department of Chemistry, University of Cyprus, P.O. Box 20537, 1678 Nicosia, Cyprus
| | - Ralf Schweins
- Large Scale Structures Group, Institut Laue-Langevin, DS/LSS, 71 Avenue des Martyrs, CS 20 156, 38042 Grenoble, France
| | - Christophe Chassenieux
- Le Mans Université, IMMM UMR CNRS6283, Département Polymères, Colloı̈des, Interfaces, av. O. Messiaen, Cedex 9 72085 Le Mans, France
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22
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Dyakonova MA, Gotzamanis G, Niebuur BJ, Vishnevetskaya NS, Raftopoulos KN, Di Z, Filippov SK, Tsitsilianis C, Papadakis CM. pH Responsiveness of hydrogels formed by telechelic polyampholytes. Soft Matter 2017; 13:3568-3579. [PMID: 28443918 DOI: 10.1039/c7sm00315c] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
We investigate the influence of pH on the rheological and structural properties of hydrogels formed by hydrophobic association of the sticky ends of the triblock terpolymer poly(methyl methacrylate)-b-poly(2-(diethylamino)ethyl methacrylate-co-methacrylic acid)-b-poly(methyl methacrylate) (PMMA-b-P(DEA-co-MAA)-b-PMMA). The middle block is a weak polyampholyte having a pH dependent charge density and sign, which enables tuning of the rheological and structural properties by pH variation. Small-angle neutron scattering (SANS) studies of solutions in D2O at 0.05 wt% and pH 3.0 reveal clusters of interconnected spherical micelles having PMMA cores, stabilized by repulsive ionic interactions in the middle polyampholyte block. With increasing pH, the degree of ionization of the DEA units decreases, whereas the one of the MAA units increases, resulting in a complete loss of the correlation between these micelles. At a concentration of 3 wt% at low pH values, the system forms a gel with charged fuzzy spheres from PMMA interacting via a screened Coulomb potential. With increasing pH, the gel disintegrates due to the decrease in the effective charge on the micelles. At both concentrations, the hydrophobic aggregation of micelles is observed near the isoelectric point. At pH 3.0-7.4, the autocorrelation functions measured by rotational dynamic light scattering at 3 wt% exhibit a decay steeper than single exponential, which confirms that the gels are frozen, presumably due to the glassy PMMA cores and hydrophobic interpolyelectrolyte complexes. At pH 11, the diffusion of single micelles is observed in addition to the frozen dynamics.
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Affiliation(s)
- Margarita A Dyakonova
- Fachgebiet Physik weicher Materie, Physik-Department, Technische Universität München, James-Franck-Str. 1, 85748 Garching, Germany.
| | - George Gotzamanis
- Department of Chemical Engineering, University of Patras, 26504 Patras, Greece.
| | - Bart-Jan Niebuur
- Fachgebiet Physik weicher Materie, Physik-Department, Technische Universität München, James-Franck-Str. 1, 85748 Garching, Germany.
| | - Natalya S Vishnevetskaya
- Fachgebiet Physik weicher Materie, Physik-Department, Technische Universität München, James-Franck-Str. 1, 85748 Garching, Germany.
| | - Konstantinos N Raftopoulos
- Fachgebiet Physik weicher Materie, Physik-Department, Technische Universität München, James-Franck-Str. 1, 85748 Garching, Germany.
| | - Zhenyu Di
- Forschungszentrum Jülich GmbH, Jülich Centre for Neutron Science at MLZ, Lichtenbergstr. 1, 85747 Garching, Germany
| | - Sergey K Filippov
- Institute of Macromolecular Chemistry, Academy of Sciences of the Czech Republic, v. v. i., Heyrovský Sq. 2, 162 06 Prague 6, Czech Republic
| | | | - Christine M Papadakis
- Fachgebiet Physik weicher Materie, Physik-Department, Technische Universität München, James-Franck-Str. 1, 85748 Garching, Germany.
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23
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Papadakis CM, Tsitsilianis C. Responsive Hydrogels from Associative Block Copolymers: Physical Gelling through Polyion Complexation. Gels 2017; 3:E3. [PMID: 30920500 PMCID: PMC6318663 DOI: 10.3390/gels3010003] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2016] [Revised: 11/30/2016] [Accepted: 12/06/2016] [Indexed: 01/15/2023] Open
Abstract
The present review article highlights a specific class of responsive polymer-based hydrogels which are formed through association of oppositely charged polyion segments. The underpinning temporary three-dimensional network is constituted of hydrophilic chains (either ionic or neutral) physically crosslinked by ion pair formation arising from intermolecular polyionic complexation of oppositely charged repeating units (polyacid/polybase ionic interactions). Two types of hydrogels are presented: (i) hydrogels formed by triblock copolymers bearing oppositely charged blocks (block copolyampholytes), forming self-assembled networks; and (ii) hydrogels formed by co-assembly of oppositely charged polyelectrolyte segments belonging to different macromolecules (either block copolymers or homopolyelectrolytes). Due to the weak nature of the involved polyions, these hydrogels respond to pH and are sensitive to the presence of salts. Discussing and evaluating their solution, rheological and structural properties in dependence on pH and ionic strength, it comes out that the hydrogel properties are tunable towards potential applications.
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Affiliation(s)
- Christine M Papadakis
- Fachgebiet Physik weicher Materie, Physik-Department, Technische Universität München, James-Franck-Str. 1, 85748 Garching, Germany.
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24
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Popescu MT, Liontos G, Avgeropoulos A, Voulgari E, Avgoustakis K, Tsitsilianis C. Injectable Hydrogel: Amplifying the pH Sensitivity of a Triblock Copolypeptide by Conjugating the N-Termini via Dynamic Covalent Bonding. ACS Appl Mater Interfaces 2016; 8:17539-17548. [PMID: 27341446 DOI: 10.1021/acsami.6b03977] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
We explore the self-assembly behavior of aqueous solutions of an amphiphilic, pH-sensitive poly(l-alanine)-b-poly(l-glutamic acid)-b-poly(l-alanine), (A5E11A5) triblock copolypeptide, end-capped by benzaldehyde through Schiff base reaction. At elevated concentrations and under physiological pH (7.4) and ionic strength (0.15M), the bare copolypeptide aqueous solutions underwent a sol-gel transition after heating and slow cooling thermal treatment, forming opaque stiff gels due to a hierarchical self-assembly that led to the formation of β-sheet-based twisted super fibers (Popescu et al. Soft Matter 2015, 11, 331-342). The conjugation of the N-termini with benzaldehyde (Bz) through a Schiff base reaction amplifies the copolypeptide pH-sensitivity within a narrow pH window relevant for in vivo applications. Specifically, the dynamic character of the imine bond allowed coupling/decoupling of the Bz upon switching pH. The presence of Bz conjugates to the N-termini of the copolypeptide resulted in enhanced packing of the elementary superfibers into thick and short piles, which inhibited the ability of the system for gelation. However, partial cleavage of Bz upon lowering pH to 6.5 prompted recovery of the hydrogel. The sol-gel transition triggered by pH was reversible, due to the coupling/decoupling of the benzoic-imine dynamic covalent bonding, endowing thus the gelling system with injectability. Undesirably, the gelation temperature window was significantly reduced, which however can be regulated at physiological temperatures by using a suitable mixture of the bare and the Bz-conjugated coplypeptide. This triblock copolypeptide gelator was investigated as a scaffold for the encapsulation of polymersome nanocarriers, loaded with a hydrophilic model drug, calcein. The polymersome/polypeptide complex system showed prolonged probe release in pH 6.5, which is relevant to extracellular tumor environment, rendering the system potentially useful for sustained delivery of anticancer drugs locally in the tumor.
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Affiliation(s)
| | - George Liontos
- Department of Materials Science and Engineering, University of Ioannina , University Campus, 45110 Ioannina, Greece
| | - Apostolos Avgeropoulos
- Department of Materials Science and Engineering, University of Ioannina , University Campus, 45110 Ioannina, Greece
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25
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Xu W, Ledin PA, Iatridi Z, Tsitsilianis C, Tsukruk VV. Frontispiece: Multicompartmental Microcapsules with Orthogonal Programmable Two-Way Sequencing of Hydrophobic and Hydrophilic Cargo Release. Angew Chem Int Ed Engl 2016. [DOI: 10.1002/anie.201681661] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Affiliation(s)
- Weinan Xu
- School of Materials Science and Engineering; Georgia Institute of Technology; Atlanta GA USA
| | - Petr A. Ledin
- School of Materials Science and Engineering; Georgia Institute of Technology; Atlanta GA USA
| | | | | | - Vladimir V. Tsukruk
- School of Materials Science and Engineering; Georgia Institute of Technology; Atlanta GA USA
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26
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Xu W, Ledin PA, Iatridi Z, Tsitsilianis C, Tsukruk VV. Frontispiz: Multicompartmental Microcapsules with Orthogonal Programmable Two-Way Sequencing of Hydrophobic and Hydrophilic Cargo Release. Angew Chem Int Ed Engl 2016. [DOI: 10.1002/ange.201681661] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Affiliation(s)
- Weinan Xu
- School of Materials Science and Engineering; Georgia Institute of Technology; Atlanta GA USA
| | - Petr A. Ledin
- School of Materials Science and Engineering; Georgia Institute of Technology; Atlanta GA USA
| | | | | | - Vladimir V. Tsukruk
- School of Materials Science and Engineering; Georgia Institute of Technology; Atlanta GA USA
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27
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Xu W, Ledin PA, Iatridi Z, Tsitsilianis C, Tsukruk VV. Multicompartmental Microcapsules with Orthogonal Programmable Two‐Way Sequencing of Hydrophobic and Hydrophilic Cargo Release. Angew Chem Int Ed Engl 2016; 55:4908-13. [DOI: 10.1002/anie.201600383] [Citation(s) in RCA: 55] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2016] [Revised: 02/08/2016] [Indexed: 11/12/2022]
Affiliation(s)
- Weinan Xu
- School of Materials Science and Engineering Georgia Institute of Technology Atlanta GA USA
| | - Petr A. Ledin
- School of Materials Science and Engineering Georgia Institute of Technology Atlanta GA USA
| | | | | | - Vladimir V. Tsukruk
- School of Materials Science and Engineering Georgia Institute of Technology Atlanta GA USA
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28
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Xu W, Ledin PA, Iatridi Z, Tsitsilianis C, Tsukruk VV. Multicompartmental Microcapsules with Orthogonal Programmable Two‐Way Sequencing of Hydrophobic and Hydrophilic Cargo Release. Angew Chem Int Ed Engl 2016. [DOI: 10.1002/ange.201600383] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Affiliation(s)
- Weinan Xu
- School of Materials Science and Engineering Georgia Institute of Technology Atlanta GA USA
| | - Petr A. Ledin
- School of Materials Science and Engineering Georgia Institute of Technology Atlanta GA USA
| | | | | | - Vladimir V. Tsukruk
- School of Materials Science and Engineering Georgia Institute of Technology Atlanta GA USA
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29
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Chassenieux C, Tsitsilianis C. Recent trends in pH/thermo-responsive self-assembling hydrogels: from polyions to peptide-based polymeric gelators. Soft Matter 2016; 12:1344-1359. [PMID: 26781351 DOI: 10.1039/c5sm02710a] [Citation(s) in RCA: 77] [Impact Index Per Article: 9.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
In this article, we highlight some recent developments in "smart" physical hydrogels achieved by self-assembling of block type macromolecules. More precisely we focus on two interesting types of gelators namely conventional ionic (or ionogenic) block copolymers and peptide-based polymers having as a common feature their responsiveness to pH and/or temperature which are the main triggers used for potential biomedical applications. Taking advantage of the immense skills of conventional block copolymer hydrogelators, namely macromolecular design, self-assembling mechanism, gel rheological properties, responsiveness to various triggers and innovative applications, the development of novel self-assembling gelators, integrating the new knowledge emerging from the peptide-based systems, opens new horizons towards bio-inspired technologies.
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Affiliation(s)
- Christophe Chassenieux
- LUNAM Université, Université du Maine, IMMM-UMR CNRS 6283, Département Polymères, Colloides et Interfaces, av. O. Messiaen, 72085 Le Μans cedex 9, France
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30
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Papadimitriou KD, Skountzos EN, Gkermpoura SS, Polyzos I, Mavrantzas VG, Galiotis C, Tsitsilianis C. Molecular Modeling Combined with Advanced Chemistry for the Rational Design of Efficient Graphene Dispersing Agents. ACS Macro Lett 2016; 5:24-29. [PMID: 35668598 DOI: 10.1021/acsmacrolett.5b00755] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Pyrene-functional PMMAs were prepared via ATRP-controlled polymerization and click reaction, as efficient dispersing agents for the exfoliation of few-layered graphene sheets (GS) in easily processable low boiling point chloroform. In parallel, detailed atomistic simulations showed fine dispersion of the GS/polymer hybrids in good agreement with the experiment. Moreover, the molecular dynamics simulations revealed interesting conformations (bridges, loops, dangling ends, free chains) of GS/polymer hybrids and allowed us to monitor their time evolution both in solution and in the polymer nanocomposite where the solvent molecules were replaced with PMMA chains. Microscopic information about these structures is very important for optimizing mechanical performance. It seems that the combination of atomistic simulation with advanced chemistry constitutes a powerful tool for the design of effective graphene dispersing agents that could be used for the production of graphene-based nanocomposites with tailor-made mechanical properties.
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Affiliation(s)
- Konstantinia D. Papadimitriou
- Foundation
of Research and Technology Hellas, Institute of Chemical Engineering Sciences (FORTH/ICE-HT), Stadiou Str., P.O. Box 1414, GR 26504, Rio-Patras, Greece
- Department
of Chemical Engineering, University of Patras, GR 26504, Patras, Greece
| | - Emmanuel N. Skountzos
- Foundation
of Research and Technology Hellas, Institute of Chemical Engineering Sciences (FORTH/ICE-HT), Stadiou Str., P.O. Box 1414, GR 26504, Rio-Patras, Greece
- Department
of Chemical Engineering, University of Patras, GR 26504, Patras, Greece
| | - Sandra S. Gkermpoura
- Foundation
of Research and Technology Hellas, Institute of Chemical Engineering Sciences (FORTH/ICE-HT), Stadiou Str., P.O. Box 1414, GR 26504, Rio-Patras, Greece
- Department
of Chemical Engineering, University of Patras, GR 26504, Patras, Greece
| | - Ioannis Polyzos
- Foundation
of Research and Technology Hellas, Institute of Chemical Engineering Sciences (FORTH/ICE-HT), Stadiou Str., P.O. Box 1414, GR 26504, Rio-Patras, Greece
| | - Vlasis G. Mavrantzas
- Foundation
of Research and Technology Hellas, Institute of Chemical Engineering Sciences (FORTH/ICE-HT), Stadiou Str., P.O. Box 1414, GR 26504, Rio-Patras, Greece
- Department
of Chemical Engineering, University of Patras, GR 26504, Patras, Greece
- Particle
Technology Laboratory, Department of Mechanical and Process Engineering, ETH-Z, CH-8093 Zürich, Switzerland
| | - Costas Galiotis
- Foundation
of Research and Technology Hellas, Institute of Chemical Engineering Sciences (FORTH/ICE-HT), Stadiou Str., P.O. Box 1414, GR 26504, Rio-Patras, Greece
- Department
of Chemical Engineering, University of Patras, GR 26504, Patras, Greece
| | - Constantinos Tsitsilianis
- Foundation
of Research and Technology Hellas, Institute of Chemical Engineering Sciences (FORTH/ICE-HT), Stadiou Str., P.O. Box 1414, GR 26504, Rio-Patras, Greece
- Department
of Chemical Engineering, University of Patras, GR 26504, Patras, Greece
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31
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Abstract
We report the synthesis and the pH dependent structural and rheological properties of a telechelic polyampholyte associative polymer, composed of a random polyampholyte central block, end-capped by shorter hydrophobic blocks [C-b-(A-co-B)-b-C block/random terpolymer type].
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32
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Dyakonova MA, Berezkin AV, Kyriakos K, Gkermpoura S, Popescu MT, Filippov SK, Štěpánek P, Di Z, Tsitsilianis C, Papadakis CM. Salt-Induced Changes in Triblock Polyampholyte Hydrogels: Computer Simulations and Rheological, Structural, and Dynamic Characterization. Macromolecules 2015. [DOI: 10.1021/acs.macromol.5b01746] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Margarita A. Dyakonova
- Fachgebiet
Physik weicher Materie, Physik-Department, Technische Universität München, James-Franck-Str. 1, 85748 Garching, Germany
| | - Anatoly V. Berezkin
- Fachgebiet
Physik weicher Materie, Physik-Department, Technische Universität München, James-Franck-Str. 1, 85748 Garching, Germany
| | - Konstantinos Kyriakos
- Fachgebiet
Physik weicher Materie, Physik-Department, Technische Universität München, James-Franck-Str. 1, 85748 Garching, Germany
| | - Sandra Gkermpoura
- Department
of Chemical Engineering, University of Patras, 26504 Patras, Greece
| | - Maria T. Popescu
- Department
of Chemical Engineering, University of Patras, 26504 Patras, Greece
| | - Sergey K. Filippov
- Institute
of Macromolecular Chemistry, Academy of Sciences of the Czech Republic, v. v. i., Heyrovský Sq. 2, 162
06 Prague 6, Czech Republic
| | - Petr Štěpánek
- Institute
of Macromolecular Chemistry, Academy of Sciences of the Czech Republic, v. v. i., Heyrovský Sq. 2, 162
06 Prague 6, Czech Republic
| | - Zhenyu Di
- Jülich
Centre for Neutron Science at MLZ, Outstation at MLZ, Forschungszentrum Jülich GmbH, Lichtenbergstr. 1, 85748 Garching, Germany
| | | | - Christine M. Papadakis
- Fachgebiet
Physik weicher Materie, Physik-Department, Technische Universität München, James-Franck-Str. 1, 85748 Garching, Germany
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33
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Gkermpoura S, Obiols-Rabasa M, Iatridi Z, Tsitsilianis C. Thermo-Resistant Soft Glassy Suspensions of Polymeric Micellar Nanoparticles in Ionic Liquid. ACS Appl Mater Interfaces 2015; 7:12411-12421. [PMID: 25634906 DOI: 10.1021/am507587s] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
We report the rheological and structural properties of a suspension comprising poly(ethylene oxide)-polystyrene-poly(ethylene oxide) core-shell micellar nanoparticles dispersed in 1-butyl-3-methylimidazolium hexafluorophosphate ionic liquid. A liquid to soft solid transition was observed at a copolymer concentration of 10 wt % above which an elastic soft material was formed, which was composed of non-ordered jammed core-shell micellar nanoparticles. In the soft solid state, a significant reduction in the size of the nanoparticles, approaching hard sphere behavior, was observed by small-angle X-ray scattering which is attributed to compression of the soft poly(ethylene oxide) coronas. The nonvolatile ionic liquid-based glassy soft solid formed exhibited remarkable thermal stability with a melting temperature of 141 °C at 20 wt % copolymer, which renders it suitable for applications involving elevated temperatures and/or reduced pressure where water-based formulations are inappropriate.
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Affiliation(s)
- Sandra Gkermpoura
- †Department of Chemical Engineering, University of Patras, 26504 Patras, Greece
| | - Marc Obiols-Rabasa
- ‡Division of Physical Chemistry, Department of Chemistry, Lund University, SE-221 00 Lund, Sweden
| | - Zacharoula Iatridi
- †Department of Chemical Engineering, University of Patras, 26504 Patras, Greece
| | - Constantinos Tsitsilianis
- †Department of Chemical Engineering, University of Patras, 26504 Patras, Greece
- §Institute of Chemical Engineering Sciences (ICEHT/FORTH), 26504 Patras, Greece
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34
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Affiliation(s)
- Weinan Xu
- School
of Materials Science and Engineering, Georgia Institute of Technology, Atlanta, Georgia 30332-0245, United States
| | - Petr A. Ledin
- School
of Materials Science and Engineering, Georgia Institute of Technology, Atlanta, Georgia 30332-0245, United States
| | - Zacharoula Iatridi
- Department
of Chemical Engineering, University of Patras, 26504 Patras, Greece
- Institute of Chemical
Engineering Sciences (FORTH/ICE-HT), 26504 Patras, Greece
| | - Constantinos Tsitsilianis
- Department
of Chemical Engineering, University of Patras, 26504 Patras, Greece
- Institute of Chemical
Engineering Sciences (FORTH/ICE-HT), 26504 Patras, Greece
| | - Vladimir V. Tsukruk
- School
of Materials Science and Engineering, Georgia Institute of Technology, Atlanta, Georgia 30332-0245, United States
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35
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Popescu MT, Liontos G, Avgeropoulos A, Tsitsilianis C. Stimuli responsive fibrous hydrogels from hierarchical self-assembly of a triblock copolypeptide. Soft Matter 2015; 11:331-342. [PMID: 25379651 DOI: 10.1039/c4sm02092h] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
In this work, the self-assembly behavior and pH responsiveness of a triblock copolypeptide in aqueous media are demonstrated. The copolypeptide was composed of a central pH responsive poly(l-glutamic acid) (PGA), flanked by two hydrophobic poly(l-alanine) blocks (PAla) (PAla5-PGA11-PAla5). This system showed a pH-responsive transition from short tapes to spherical aggregates by increasing the pH, as a result of deprotonation of the PGA block and a conformational change from α-helix to random coil. Increasing the ionic strength to physiological conditions (0.15 M) has triggered fibrillar self-assembly through intermolecular hydrogen bonding of PAla end-blocks that form β-sheet nanostructures, in conjunction with charge screening of the central random coil PGA segments. At elevated concentrations a thermo-responsive free supporting hydrogel was obtained, consisting of rigid β-sheet based twisted superfibers, resulting from hierarchical self-assembly of the copolypeptide. Yet, morphological transformation of this nanostructure was observed upon switching the pH from physiological conditions to pH 4. An unexpected morphology constituted of α-helix-based giant nanobelts was observed as a consequence of the secondary peptide transitions.
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36
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Popescu MT, Tasis D, Papadimitriou KD, Gkermpoura S, Galiotis C, Tsitsilianis C. Colloidal stabilization of graphene sheets by ionizable amphiphilic block copolymers in various media. RSC Adv 2015. [DOI: 10.1039/c5ra17916e] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023] Open
Abstract
Graphene nanosheet suspensions can be produced in organic solvents, water or ionic liquids by using the same ionogenic block copolymers.
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Affiliation(s)
- Maria-Teodora Popescu
- Foundation of Research and Technology Hellas
- Institute of Chemical Engineering Sciences (ICE-HT)
- 26504 Rio Patras
- Greece
| | - Dimitrios Tasis
- Foundation of Research and Technology Hellas
- Institute of Chemical Engineering Sciences (ICE-HT)
- 26504 Rio Patras
- Greece
- Department of Chemistry
| | - Konstantinia D. Papadimitriou
- Foundation of Research and Technology Hellas
- Institute of Chemical Engineering Sciences (ICE-HT)
- 26504 Rio Patras
- Greece
| | - Sandra Gkermpoura
- Foundation of Research and Technology Hellas
- Institute of Chemical Engineering Sciences (ICE-HT)
- 26504 Rio Patras
- Greece
- Department of Chemical Engineering
| | - Costas Galiotis
- Foundation of Research and Technology Hellas
- Institute of Chemical Engineering Sciences (ICE-HT)
- 26504 Rio Patras
- Greece
- Department of Chemical Engineering
| | - Constantinos Tsitsilianis
- Foundation of Research and Technology Hellas
- Institute of Chemical Engineering Sciences (ICE-HT)
- 26504 Rio Patras
- Greece
- Department of Chemical Engineering
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37
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Iatridi Z, Lencina MMS, Tsitsilianis C. PNIPAM-based heteroarm star-graft quarterpolymers: synthesis, characterization and pH-dependent thermoresponsiveness in aqueous media. Polym Chem 2015. [DOI: 10.1039/c5py00393h] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
We report the design of PSn(P2VP-b-PAA-g-PNIPAM)n heteroarm star-graft quarterpolymers, the thermoresponsiveness of which is strongly dependent on pH ionic strength, and their macromolecular features, e.g. arm number and grafting density.
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Affiliation(s)
- Zacharoula Iatridi
- Department of Chemical Engineering
- University of Patras
- 26504 Patras
- Greece
| | | | - Constantinos Tsitsilianis
- Department of Chemical Engineering
- University of Patras
- 26504 Patras
- Greece
- Institute of Chemical Engineering Sciences ICE/HT-FORTH
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38
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Dyakonova MA, Stavrouli N, Popescu MT, Kyriakos K, Grillo I, Philipp M, Jaksch S, Tsitsilianis C, Papadakis CM. Physical Hydrogels via Charge Driven Self-Organization of a Triblock Polyampholyte – Rheological and Structural Investigations. Macromolecules 2014. [DOI: 10.1021/ma501671s] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- M. A. Dyakonova
- Fachgebiet
Physik weicher Materie/Lehrstuhl für Funktionelle Materialien,
Physik-Department, Technische Universität München, James-Franck-Strasse
1, 85748 Garching, Germany
| | - N. Stavrouli
- Department
of Chemical Engineering, University of Patras, 26504 Patras, Greece
- Institute
of Chemical Engineering Sciences, ICE/HT-FORTH, P.O. Box 1414, 26504 Patras, Greece
| | - M. T. Popescu
- Department
of Chemical Engineering, University of Patras, 26504 Patras, Greece
- Institute
of Chemical Engineering Sciences, ICE/HT-FORTH, P.O. Box 1414, 26504 Patras, Greece
| | - K. Kyriakos
- Fachgebiet
Physik weicher Materie/Lehrstuhl für Funktionelle Materialien,
Physik-Department, Technische Universität München, James-Franck-Strasse
1, 85748 Garching, Germany
| | - I. Grillo
- Large
Scale Structures Group, Institut Laue-Langevin, 6, rue Jules Horowitz, 38042 Grenoble, France
| | - M. Philipp
- Fachgebiet
Physik weicher Materie/Lehrstuhl für Funktionelle Materialien,
Physik-Department, Technische Universität München, James-Franck-Strasse
1, 85748 Garching, Germany
| | - S. Jaksch
- Jülich
Centre for Neutron Science at MLZ, Forschungszentrum Jülich GmbH, Lichtenbergstrasse
1, 85747 Garching, Germany
| | - C. Tsitsilianis
- Department
of Chemical Engineering, University of Patras, 26504 Patras, Greece
- Institute
of Chemical Engineering Sciences, ICE/HT-FORTH, P.O. Box 1414, 26504 Patras, Greece
| | - C. M. Papadakis
- Fachgebiet
Physik weicher Materie/Lehrstuhl für Funktionelle Materialien,
Physik-Department, Technische Universität München, James-Franck-Strasse
1, 85748 Garching, Germany
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39
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Popescu MT, Tasis D, Tsitsilianis C. Ionizable Star Copolymer-Assisted Graphene Phase Transfer between Immiscible Liquids: Organic Solvent/Water/Ionic Liquid. ACS Macro Lett 2014; 3:981-984. [PMID: 35610780 DOI: 10.1021/mz500443q] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
Abstract
The present study reports on the development of a simple two-step process toward the isolation of nearly defect-free mono- and few-layer graphenes in various media. This was achieved by liquid phase pre-exfoliation of pristine graphite in the presence of an ionizable PSnP2VPn heteroarm star copolymer in an organic solvent and subsequent graphene shuttle between immiscible media, that is, organic solvent/water and water/ionic liquid. This polymer-assisted phase transfer of graphene sheets gave rise to enrichment of suspended nanostructures in monolayers, especially in an aqueous environment. The exfoliation efficiency was assessed through Raman and electron microscopy. Relatively high concentration suspensions of efficiently exfoliated graphene sheets of large size and in high solubilization yield, could be prepared in any kind of solvent, that is, organic low boiling point medium, aqueous environment, or ionic liquid, whereas the shuttle transfer was found to be a reversible process between organic and aqueous phases.
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Affiliation(s)
- Maria-Theodora Popescu
- Foundation of
Research and Technology Hellas, Institute of Chemical Engineering
Sciences (ICE-HT), P.O. Box 1414, 26504 Patras, Greece
- Department
of Chemical Engineering, University of Patras, 26504 Patras, Greece
| | - Dimitrios Tasis
- Foundation of
Research and Technology Hellas, Institute of Chemical Engineering
Sciences (ICE-HT), P.O. Box 1414, 26504 Patras, Greece
- Department
of Chemistry, University of Ioannina, 45110 Ioannina, Greece
| | - Constantinos Tsitsilianis
- Foundation of
Research and Technology Hellas, Institute of Chemical Engineering
Sciences (ICE-HT), P.O. Box 1414, 26504 Patras, Greece
- Department
of Chemical Engineering, University of Patras, 26504 Patras, Greece
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40
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Popescu MT, Korogiannaki M, Marikou K, Tsitsilianis C. CBABC terpolymer-based nanostructured vesicles with tunable membrane permeability as potential hydrophilic drug nanocarriers. POLYMER 2014. [DOI: 10.1016/j.polymer.2014.04.034] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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41
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Abstract
We report the interfacial assembly of amphiphilic heteroarm star copolymers (PSnP2VPn and PSn(P2VP-b-PtBA)n (n = 28 arms)) on graphene oxide flakes at the air-water interface. Adsorption, spreading, and ordering of star polymer micelles on the surface of the basal plane and edge of monolayer graphene oxide sheets were investigated on a Langmuir trough. This interface-mediated assembly resulted in micelle-decorated graphene oxide sheets with uniform spacing and organized morphology. We found that the surface activity of solvated graphene oxide sheets enables star polymer surfactants to subsequently adsorb on the presuspended graphene oxide sheets, thereby producing a bilayer complex. The positively charged heterocyclic pyridine-containing star polymers exhibited strong affinity onto the basal plane and edge of graphene oxide, leading to a well-organized and long-range ordered discrete micelle assembly. The preferred binding can be related to the increased conformational entropy due to the reduction of interarm repulsion. The extent of coverage was tuned by controlling assembly parameters such as concentration and solvent polarity. The polymer micelles on the basal plane remained incompressible under lateral compression in contrast to ones on the water surface due to strongly repulsive confined arms on the polar surface of graphene oxide and a preventive barrier in the form of the sheet edges. The densely packed biphasic tile-like morphology was evident, suggesting the high interfacial stability and mechanically stiff nature of graphene oxide sheets decorated with star polymer micelles. This noncovalent assembly represents a facile route for the control and fabrication of graphene oxide-inclusive ultrathin hybrid films applicable for layered nanocomposites.
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Affiliation(s)
- Ikjun Choi
- School of Materials Science and Engineering, Georgia Institute of Technology, Atlanta, Georgia 30332-0245, United States
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42
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Sheiko SS, Zhou J, Arnold J, Neugebauer D, Matyjaszewski K, Tsitsilianis C, Tsukruk VV, Carrillo JMY, Dobrynin AV, Rubinstein M. Perfect mixing of immiscible macromolecules at fluid interfaces. Nat Mater 2013; 12:735-740. [PMID: 23708330 DOI: 10.1038/nmat3651] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/21/2012] [Accepted: 04/10/2013] [Indexed: 05/29/2023]
Abstract
The difficulty of mixing chemically incompatible substances--in particular macromolecules and colloidal particles--is a canonical problem limiting advances in fields ranging from health care to materials engineering. Although the self-assembly of chemically different moieties has been demonstrated in coordination complexes, supramolecular structures, and colloidal lattices among other systems, the mechanisms of mixing largely rely on specific interfacing of chemically, physically or geometrically complementary objects. Here, by taking advantage of the steric repulsion between brush-like polymers tethered to surface-active species, we obtained long-range arrays of perfectly mixed macromolecules with a variety of polymer architectures and a wide range of chemistries without the need of encoding specific complementarity. The net repulsion arises from the significant increase in the conformational entropy of the brush-like polymers with increasing distance between adjacent macromolecules at fluid interfaces. This entropic-templating assembly strategy enables long-range patterning of thin films on sub-100 nm length scales.
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Affiliation(s)
- Sergei S Sheiko
- Department of Chemistry, University of North Carolina, Chapel Hill, North Carolina 27599-3290, USA.
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43
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Abstract
The present study reports on the development of composite gold nanoparticles (AuNPs)/polymersome formulations, based on pH-responsive biocompatible polymer vesicles integrating prefunctionalized AuNPs, doped with a hydrophobic model probe for improved multimodal drug delivery. The polymer vesicles were prepared from an amphiphilic pentablock terpolymer poly(ε-caprolactone)-b-poly(ethylene oxide)-b-poly(2-vinylpyridine)-b-poly(ethylene oxide)-b-poly(ε-caprolactone) (PCL-PEO-P2VP-PEO-PCL), consisting of a pH-sensitive and biodegradable P2VP/PCL membrane, surrounded by neutral hydrophilic PEO looping chains. Additionally, partial quaternization of the P2VP block has been performed to introduce cationic moieties. Water-dispersible AuNPs carrying a hydrophobic molecule were encapsulated in the hydrophilic aqueous lumen of the vesicles, and the release was monitored at pH conditions simulating physiological and tumor environments. The complex delivery of the cargos from these vesicles showed improved and controlled kinetics relative to the individual nanocarriers, which could be further tuned by pH and chemical modification of the membrane forming block.
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Affiliation(s)
| | - Constantinos Tsitsilianis
- Department of Chemical
Engineering, University of Patras, 26504, Patras, Greece
- Institute of Chemical Engineering Sciences, ICE/HT-FORTH, P.O. Box 1414, 26504
Patras, Greece
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44
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Affiliation(s)
- Ikjun Choi
- School of Materials Science
and Engineering, Georgia Institute of Technology, Atlanta, Georgia 30332-0245, United States
| | - Sidney T. Malak
- School of Materials Science
and Engineering, Georgia Institute of Technology, Atlanta, Georgia 30332-0245, United States
| | - Weinan Xu
- School of Materials Science
and Engineering, Georgia Institute of Technology, Atlanta, Georgia 30332-0245, United States
| | - William T. Heller
- Biology & Soft Matter Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, United States
| | - Constantinos Tsitsilianis
- Department of Chemical Engineering, University of Patras, 26504 Patras, Greece, and Institute
of Chemical Engineering and High Temperature Processes (FORTH/ICE-HT)
| | - Vladimir V. Tsukruk
- School of Materials Science
and Engineering, Georgia Institute of Technology, Atlanta, Georgia 30332-0245, United States
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45
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Kodiyath R, Choi I, Patterson B, Tsitsilianis C, Tsukruk VV. Interfacial behavior of pH responsive ampholytic heteroarm star block terpolymers. POLYMER 2013. [DOI: 10.1016/j.polymer.2012.12.031] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
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46
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Stavrouli N, Iatridi Z, Aubry T, Tsitsilianis C. Three different types of physical gels originate from a common triblock copolymer precursor: the case of an ionomer gel. Polym Chem 2013. [DOI: 10.1039/c2py21024j] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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47
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Popescu MT, Tsitsilianis C, Papadakis CM, Adelsberger J, Balog S, Busch P, Hadjiantoniou NA, Patrickios CS. Stimuli-Responsive Amphiphilic Polyelectrolyte Heptablock Copolymer Physical Hydrogels: An Unusual pH-Response. Macromolecules 2012. [DOI: 10.1021/ma300222d] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Maria-Teodora Popescu
- Department of Chemical Engineering, University of Patras, 26504, Patras, Greece
- Institute of Chemical Engineering and High Temperature Chemical Processes, ICE/HT-FORTH, P.O. Box 1414, 26504 Patras, Greece
| | - Constantinos Tsitsilianis
- Department of Chemical Engineering, University of Patras, 26504, Patras, Greece
- Institute of Chemical Engineering and High Temperature Chemical Processes, ICE/HT-FORTH, P.O. Box 1414, 26504 Patras, Greece
| | - Christine M. Papadakis
- Fachgebiet Physik weicher Materie,
Physikdepartment, Technische Universität München, James-Franck-Strasse 1, 85747 Garching, Germany
| | - Joseph Adelsberger
- Fachgebiet Physik weicher Materie,
Physikdepartment, Technische Universität München, James-Franck-Strasse 1, 85747 Garching, Germany
| | - Sandor Balog
- Paul Scherrer Institut, 5232 Villigen PSI, Switzerland
| | - Peter Busch
- Jülich Centre for Neutron
Science at FRM II, Forschungszentrum Jülich GmbH, Lichtenbergstrasse 1, 85747 Garching, Germany
| | | | - Costas S. Patrickios
- Department of Chemistry, University of Cyprus, P.O. Box 20537, 1678 Nicosia,
Cyprus
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48
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Suntivich R, Choi I, Gupta MK, Tsitsilianis C, Tsukruk VV. Gold nanoparticles grown on star-shaped block copolymer monolayers. Langmuir 2011; 27:10730-10738. [PMID: 21790125 DOI: 10.1021/la2022566] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
We report on the growth of gold nanoparticles in polystyrene/poly(2-vinyl pyridine) (PS/P2VP) star-shaped block copolymer monolayers. These amphiphilic PS(n)P2VP(n) heteroarm star copolymers differ in molecular weight (149,000 and 529,000 Da) and the number of arms (9 and 28). Langmuir-Blodgett (LB) deposition was utilized to control the spatial arrangement of P2VP arms and their ability to reduce gold nanoparticles. The PS(n)P2VP(n) monolayer acted as a template for gold nanoparticle growth because of the monolayer's high micellar stability at the liquid-solid interface, uniform domain morphology, and ability to adsorb Au ions from the water subphase. UV-vis spectra and AFM and TEM images confirmed the formation of individual gold nanoparticles with an average size of 6 ± 1 nm in the P2VP-rich outer phase. This facile strategy is critical to the formation of ultrathin polymer-gold nanocomposite layers over large surface areas with confined, one-sided positioning of gold nanoparticles in an outer P2VP phase at polymer-silicon interfaces.
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Affiliation(s)
- Rattanon Suntivich
- School of Materials Science and Engineering, Georgia Institute of Technology, Atlanta, Georgia 30332-0245, USA
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49
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Popescu MT, Mourtas S, Pampalakis G, Antimisiaris SG, Tsitsilianis C. pH-Responsive Hydrogel/Liposome Soft Nanocomposites For Tuning Drug Release. Biomacromolecules 2011; 12:3023-30. [DOI: 10.1021/bm2006483] [Citation(s) in RCA: 79] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
| | - Spyridon Mourtas
- Department of Pharmacy, School of Health Sciences, University of Patras 26504, Patras, Greece
| | - Georgios Pampalakis
- Department of Pharmacy, School of Health Sciences, University of Patras 26504, Patras, Greece
| | - Sophia G. Antimisiaris
- Department of Pharmacy, School of Health Sciences, University of Patras 26504, Patras, Greece
- Institute of Chemical Engineering and High Temperature Chemical Processes, ICE/HT-FORTH, P.O. Box 1414, 26504 Patras, Greece
| | - Constantinos Tsitsilianis
- Department of Chemical Engineering, University of Patras 26504, Patras, Greece
- Institute of Chemical Engineering and High Temperature Chemical Processes, ICE/HT-FORTH, P.O. Box 1414, 26504 Patras, Greece
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50
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Iatridi Z, Tsitsilianis C. pH responsive self assemblies from an A(n)-core-(B-b-C)n heteroarm star block terpolymer bearing oppositely charged segments. Chem Commun (Camb) 2011; 47:5560-2. [PMID: 21461436 DOI: 10.1039/c0cc05507g] [Citation(s) in RCA: 51] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Abstract
We report on the association capability of a novel multisegmented, multiarm star terpolymer to form a diversity of pH-responsive amphoteric micellar nanostructured self-assemblies.
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Affiliation(s)
- Zacharoula Iatridi
- Department of Chemical Engineering, University of Patras, 26504 Patras, Greece
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