1
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Roseau M, Chausset-Boissarie L, Gremetz S, Roth PMC, Penhoat M. Multiple wavelength (365-475 nm) complete actinometric characterization of Corning ® Lab Photo Reactor using azobenzene as a highly soluble, cheap and robust chemical actinometer. Photochem Photobiol Sci 2022; 21:421-432. [PMID: 35147919 DOI: 10.1007/s43630-022-00171-w] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2021] [Accepted: 01/08/2022] [Indexed: 11/29/2022]
Abstract
The characterization of commercially available Corning® Lab Photo Reactor by actinometry at different wavelengths (365, 385, 405 and 475 nm) using azobenzene E ↔ Z photoisomerization is reported. By comparison with photon fluxes determined externally using a radiometer, this method based on NMR spectroscopy is rapid, cheap, robust, reproducible and can applied to UVA-visible range, compared to previously described chemical actinometric protocols. Recalculation of isatin N2-phenylhydrazone isomerization quantum yield at 405 nm gave almost the same value as the literature data ([Formula: see text] = 0.0013) and confirmed the robustness and applicability of this methodology.
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Affiliation(s)
| | - Laëtitia Chausset-Boissarie
- USR 3290, MSAP (Miniaturisation pour la Synthèse l'Analyse et la Protéomique), Université de Lille, 59000, Lille, France
| | | | | | - Maël Penhoat
- USR 3290, MSAP (Miniaturisation pour la Synthèse l'Analyse et la Protéomique), Université de Lille, 59000, Lille, France.
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2
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Implementation of a mathematical model for the photochemical kinetics of a solid form active pharmaceutical ingredient. Int J Pharm 2019; 566:500-512. [PMID: 31129341 DOI: 10.1016/j.ijpharm.2019.05.054] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2018] [Revised: 05/17/2019] [Accepted: 05/20/2019] [Indexed: 11/22/2022]
Abstract
We present here the development of a photochemical model used to quantify the risk to photodegradation of a solid drug substance. A key feature of the proposed model development is streamlined estimation of the dependence of the absorption spectra and the quantum yield to the wavelength. A mathematical description of the relationship between the quantum yield and the wavelength enables estimation of photodegradation kinetics under any light anticipated to be encountered in the manufacturing environment. The system studied here consisted of a first order irreversible transformation (A → B(1Φ)) and the formalism strongly suggested the quantum yield was constant over the relevant wavelength range. The predictive power of the model enabled the design of a control strategy to limit the formation of the photo-degradant to very low levels. Also presented are insights obtained from quantum mechanical modeling of the electronic transitions associated with the UV absorption spectra.
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3
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Reinfelds M, Hermanns V, Halbritter T, Wachtveitl J, Braun M, Slanina T, Heckel A. A Robust, Broadly Absorbing Fulgide Derivative as a Universal Chemical Actinometer for the UV to NIR Region. CHEMPHOTOCHEM 2019. [DOI: 10.1002/cptc.201900010] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Affiliation(s)
- Matiss Reinfelds
- Institute for Organic Chemistry and Chemical BiologyGoethe-University Frankfurt Max-von-Laue-Str. 7 60438 Frankfurt (M Germany
| | - Volker Hermanns
- Institute for Organic Chemistry and Chemical BiologyGoethe-University Frankfurt Max-von-Laue-Str. 7 60438 Frankfurt (M Germany
| | - Thomas Halbritter
- Institute for Organic Chemistry and Chemical BiologyGoethe-University Frankfurt Max-von-Laue-Str. 7 60438 Frankfurt (M Germany
- Department of ChemistryUniversity of Iceland, Science Institute Dunhaga 3 Iceland
| | - Josef Wachtveitl
- Institute for Physical and Theoretical ChemistryGoethe University Frankfurt Max-von-Laue-Str. 7 60438 Frankfurt (M Germany
| | - Markus Braun
- Institute for Physical and Theoretical ChemistryGoethe University Frankfurt Max-von-Laue-Str. 7 60438 Frankfurt (M Germany
| | - Tomáš Slanina
- Institute for Organic Chemistry and Chemical BiologyGoethe-University Frankfurt Max-von-Laue-Str. 7 60438 Frankfurt (M Germany
| | - Alexander Heckel
- Institute for Organic Chemistry and Chemical BiologyGoethe-University Frankfurt Max-von-Laue-Str. 7 60438 Frankfurt (M Germany
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4
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Roibu A, Fransen S, Leblebici ME, Meir G, Van Gerven T, Kuhn S. An accessible visible-light actinometer for the determination of photon flux and optical pathlength in flow photo microreactors. Sci Rep 2018; 8:5421. [PMID: 29615679 PMCID: PMC5882931 DOI: 10.1038/s41598-018-23735-2] [Citation(s) in RCA: 34] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2017] [Accepted: 03/20/2018] [Indexed: 11/18/2022] Open
Abstract
Coupling photochemistry with flow microreactors enables novel synthesis strategies with higher efficiencies compared to batch systems. Improving the reproducibility and understanding of the photochemical reaction mechanisms requires quantitative tools such as chemical actinometry. However, the choice of actinometric systems which can be applied in microreactors is limited, due to their short optical pathlength in combination with a large received photon flux. Furthermore, actinometers for the characterization of reactions driven by visible light between 500 and 600 nm (e.g. photosensitized oxidations) are largely missing. In this paper, we propose a new visible-light actinometer which can be applied in flow microreactors between 480 and 620 nm. This actinometric system is based on the photoisomerization reaction of a diarylethene derivative from its closed to the open form. The experimental protocol for actinometric measurements is facile and characterized by excellent reproducibility and we also present an analytical estimation to calculate the photon flux. Furthermore, we propose an experimental methodology to determine the average pathlength in microreactors using actinometric measurements. In the context of a growing research interest on using flow microreactors for photochemical reactions, the proposed visible-light actinometer facilitates the determination of the received photon flux and average pathlength in confined geometries.
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Affiliation(s)
- Anca Roibu
- Department of Chemical Engineering, KU Leuven, Celestijnenlaan 200F, 3001, Leuven, Belgium
| | - Senne Fransen
- Department of Chemical Engineering, KU Leuven, Celestijnenlaan 200F, 3001, Leuven, Belgium
| | - M Enis Leblebici
- Department of Chemical Engineering, KU Leuven, Celestijnenlaan 200F, 3001, Leuven, Belgium
| | - Glen Meir
- Department of Chemical Engineering, KU Leuven, Celestijnenlaan 200F, 3001, Leuven, Belgium
| | - Tom Van Gerven
- Department of Chemical Engineering, KU Leuven, Celestijnenlaan 200F, 3001, Leuven, Belgium
| | - Simon Kuhn
- Department of Chemical Engineering, KU Leuven, Celestijnenlaan 200F, 3001, Leuven, Belgium.
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5
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Maafi M, Al-Qarni MA. Φ-order spectrophotokinetic characterisation and quantification of trans-cis oxyresveratrol reactivity, photodegradation and actinometry. SPECTROCHIMICA ACTA. PART A, MOLECULAR AND BIOMOLECULAR SPECTROSCOPY 2018; 188:64-71. [PMID: 28692869 DOI: 10.1016/j.saa.2017.06.067] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/01/2017] [Revised: 06/13/2017] [Accepted: 06/30/2017] [Indexed: 06/07/2023]
Abstract
A new Φ-order kinetic method was proposed in this study for the investigation of trans-cis photoisomerization reaction of Oxyresveratrol (ORVT) subjected to non-isosbestic irradiation. In ethanolic media, it has been proven that forward (ΦA→Bλirr) and reverse (ΦB→Aλirr) reaction quantum yields were dependent on the monochromatic irradiation wavelength according to sigmoid patterns over the spectral ranges of their electronic absorption (260-360nm). An 11.4- and 6.6-fold increases were recorded for ΦB→Aλirr and ΦA→Bλirr, respectively. The efficiencies of the former (ΦB→Aλirr, ranging between 2.3×10-2 and 26.3×10-2) were 33 to 60% smaller than those of the respective ΦA→Bλirr measured at the irradiation wavelengths selected. Overall, between 57 and 97% degradation of the initial trans-ORVT was observed under relatively weak light intensities, with the highest values recorded at the longest wavelengths. These findings strongly recommend protection from light in all situations of this biologically important phytomolecule that possesses therapeutic value of interest to pharmaceutical applications. The Φ-order kinetics also offered a simple way to develop a reliable actinometric method that proved ORVT to be an efficient actinometer for the dynamic range 295-360nm. The usefulness of Φ-order kinetics for the investigation and quantification of phytoproducts' photodegradation was discussed.
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Affiliation(s)
- Mounir Maafi
- Leicester School of Pharmacy, De Montfort University, The Gateway, Leicester LE1 9BH, UK.
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6
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Wang YT, Gao YJ, Wang Q, Cui G. Photochromic Mechanism of a Bridged Diarylethene: Combined Electronic Structure Calculations and Nonadiabatic Dynamics Simulations. J Phys Chem A 2017; 121:793-802. [PMID: 28051866 DOI: 10.1021/acs.jpca.6b11682] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Intramolecularly bridged diarylethenes exhibit improved photocyclization quantum yields because the anti-syn isomerization that originally suppresses photocyclization in classical diarylethenes is blocked. Experimentally, three possible channels have been proposed to interpret experimental observation, but many details of photochromic mechanism remain ambiguous. In this work we have employed a series of electronic structure methods (OM2/MRCI, DFT, TDDFT, RI-CC2, DFT/MRCI, and CASPT2) to comprehensively study excited state properties, photocyclization, and photoreversion dynamics of 1,2-dicyano[2,2]metacyclophan-1-ene. On the basis of optimized stationary points and minimum-energy conical intersections, we have refined experimentally proposed photochromic mechanism. Only an S1/S0 minimum-energy conical intersection is located; thus, we can exclude the third channel experimentally proposed. In addition, we find that both photocyclization and photoreversion processes use the same S1/S0 conical intersection to decay the S1 system to the S0 state, so we can unify the remaining two channels into one. These new insights are verified by our OM2/MRCI nonadiabatic dynamics simulations. The S1 excited-state lifetimes of photocyclization and photoreversion are estimated to be 349 and 453 fs, respectively, which are close to experimentally measured values: 240 ± 60 and 250 fs in acetonitrile solution. The present study not only interprets experimental observations and refines previously proposed mechanism but also provides new physical insights that are valuable for future experiments.
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Affiliation(s)
- Ya-Ting Wang
- Key Laboratory of Theoretical and Computational Photochemistry, Ministry of Education, College of Chemistry, Beijing Normal University , Beijing 100875, China
| | - Yuan-Jun Gao
- Key Laboratory of Theoretical and Computational Photochemistry, Ministry of Education, College of Chemistry, Beijing Normal University , Beijing 100875, China
| | - Qian Wang
- Key Laboratory of Theoretical and Computational Photochemistry, Ministry of Education, College of Chemistry, Beijing Normal University , Beijing 100875, China
| | - Ganglong Cui
- Key Laboratory of Theoretical and Computational Photochemistry, Ministry of Education, College of Chemistry, Beijing Normal University , Beijing 100875, China
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7
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Modeling and Elucidation of the Kinetics of Multiple Consecutive Photoreactions AB 4 (4Φ) With Φ-order Kinetics. Application to the Photodegradation of Riboflavin. J Pharm Sci 2016; 105:3537-3548. [DOI: 10.1016/j.xphs.2016.06.030] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2016] [Revised: 06/01/2016] [Accepted: 06/06/2016] [Indexed: 11/20/2022]
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8
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Maafi M, Lee LY. Determination of Dacarbazine Φ-Order Photokinetics, Quantum Yields, and Potential for Actinometry. J Pharm Sci 2015; 104:3501-9. [DOI: 10.1002/jps.24568] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2014] [Revised: 06/11/2015] [Accepted: 06/12/2015] [Indexed: 11/07/2022]
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9
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Maafi M, Lee LY. Actinometric and Φ-order photodegradation properties of anti-cancer Sunitinib. J Pharm Biomed Anal 2015; 110:34-41. [DOI: 10.1016/j.jpba.2015.02.026] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2014] [Revised: 02/12/2015] [Accepted: 02/13/2015] [Indexed: 02/04/2023]
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10
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Maafi M, Maafi W. Quantitative assessment of photostability and photostabilisation of Fluvoxamine and its design for actinometry. Photochem Photobiol Sci 2015; 14:982-94. [DOI: 10.1039/c5pp00022j] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Wavelength-dependent forward and reverse Fluvo quantum yields have been reported.
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Affiliation(s)
- Mounir Maafi
- Leicester School of Pharmacy
- De Montfort University
- Leicester LE1 9BH
- UK
| | - Wassila Maafi
- Leicester School of Pharmacy
- De Montfort University
- Leicester LE1 9BH
- UK
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11
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Irie M, Fukaminato T, Matsuda K, Kobatake S. Photochromism of Diarylethene Molecules and Crystals: Memories, Switches, and Actuators. Chem Rev 2014; 114:12174-277. [DOI: 10.1021/cr500249p] [Citation(s) in RCA: 1755] [Impact Index Per Article: 175.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Affiliation(s)
- Masahiro Irie
- Research
Center for Smart Molecules, Rikkyo University, Nishi-Ikebukuro 3-34-1, Toshima-ku, Tokyo 171-8501, Japan
| | - Tuyoshi Fukaminato
- Research
Institute for Electronic Science, Hokkaido University, N20, W10, Kita-ku,
Sapporo 001-0020, Japan
| | - Kenji Matsuda
- Department
of Synthetic Chemistry and Biological Chemistry, Graduate School of
Engineering, Kyoto University, Katsura, Nishikyo-ku, Kyoto 615-8510, Japan
| | - Seiya Kobatake
- Department
of Applied Chemistry, Graduate School of Engineering, Osaka City University, Sugimoto 3-3-138, Sumiyoshi-ku, Osaka 558-8585, Japan
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12
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Montelukast photodegradation: Elucidation of Ф-order kinetics, determination of quantum yields and application to actinometry. Int J Pharm 2014; 471:544-52. [DOI: 10.1016/j.ijpharm.2014.05.016] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2014] [Revised: 05/06/2014] [Accepted: 05/08/2014] [Indexed: 11/30/2022]
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13
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Maafi M, Maafi W. Ф-order kinetics of photoreversible-drug reactions. Int J Pharm 2014; 471:536-43. [DOI: 10.1016/j.ijpharm.2014.05.017] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2014] [Accepted: 05/08/2014] [Indexed: 10/25/2022]
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14
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Pärs M, Gradmann M, Gräf K, Bauer P, Thelakkat M, Köhler J. Optical gating with organic building blocks. A quantitative model for the fluorescence modulation of photochromic perylene bisimide dithienylcyclopentene triads. Sci Rep 2014; 4:4316. [PMID: 24614963 PMCID: PMC3949285 DOI: 10.1038/srep04316] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2013] [Accepted: 02/20/2014] [Indexed: 11/09/2022] Open
Abstract
We investigated the capability of molecular triads, consisting of two strong fluorophores that were covalently linked to a photochromic molecule, for optical gating. Therefore we monitored the fluorescence intensity of the fluorophores as a function of the isomeric state of the photoswitch. From the analysis of our data we develop a kinetic model that allows us to predict quantitatively the degree of the fluorescence modulation as a function of the mutual intensities of the lasers that are used to induce the fluorescence and the switching of the photochromic unit. We find that the achievable contrast for the modulation of the fluorescence depends mainly on the intensity ratio of the two light beams and appears to be very robust against absolute changes of these intensities. The latter result provides valuable information for the development of all-optical circuits which would require to handle different signal strengths for the input and output levels.
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Affiliation(s)
- Martti Pärs
- Experimental Physics IV, University of Bayreuth 95440 Bayreuth, Germany
| | - Michael Gradmann
- Experimental Physics IV, University of Bayreuth 95440 Bayreuth, Germany
| | - Katja Gräf
- Applied Functional Polymers, University of Bayreuth 95440 Bayreuth, Germany
| | - Peter Bauer
- 1] Applied Functional Polymers, University of Bayreuth 95440 Bayreuth, Germany [2]
| | - Mukundan Thelakkat
- Applied Functional Polymers, University of Bayreuth 95440 Bayreuth, Germany
| | - Jürgen Köhler
- Experimental Physics IV, University of Bayreuth 95440 Bayreuth, Germany
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15
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Sumi T, Takagi Y, Yagi A, Morimoto M, Irie M. Photoirradiation wavelength dependence of cycloreversion quantum yields of diarylethenes. Chem Commun (Camb) 2014; 50:3928-30. [PMID: 24595677 DOI: 10.1039/c4cc00396a] [Citation(s) in RCA: 76] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
The cycloreversion quantum yields of compounds 1b and 2b increased upon irradiation with light at shorter wavelengths. The irradiation wavelength dependence is ascribed to the energy barrier on the 2A potential energy surface in the excited electronic state.
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Affiliation(s)
- Takaki Sumi
- Department of Chemistry and Research Center for Smart Molecules, Rikkyo University, 3-34-1 Nishi-Ikebukuro, Toshima-ku, Tokyo 171-8501, Japan.
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16
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Maafi W, Maafi M. Modelling nifedipine photodegradation, photostability and actinometric properties. Int J Pharm 2013; 456:153-64. [PMID: 23954300 DOI: 10.1016/j.ijpharm.2013.07.075] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2013] [Revised: 07/26/2013] [Accepted: 07/28/2013] [Indexed: 10/26/2022]
Abstract
BACKGROUND The photodegradation of drugs obeying unimolecular mechanisms such as that of nifedipine (NIF) were usually characterised in the literature by zero-, first- and second-order kinetics. This approach has been met with varying success. This paper addresses this issue and proposes a novel approach for unimolecular photodegradation kinetics. The photodegradation of the cardiovascular drug nifedipine is investigated within this framework. METHODS Experimental kinetic data of nifedipine photodegradation were obtained by continuous monochromatic irradiation and DAD analysis. Fourth-order Runge-Kutta calculated kinetic data served for the validation of the new semi-empirical integrated rate-law model proposed in this study. RESULTS A new model equation has been developed and proposed which faithfully describes the kinetic behaviour of NIF in solution for non-isosbestic irradiations at wavelengths where both NIF and its photoproduct absorb. NIF absolute quantum yield values were determined and found to increase with irradiation wavelength according to a defined sigmoid relationship. The effects of increasing NIF or excipients' concentrations on NIF kinetics were successfully modelled and found to improve NIF photostability. The potential of NIF for actinometry has been explored and evaluated. A new reaction order (the so-called Φ-order) has been identified and specifically proposed for unimolecular photodegradation reactions. CONCLUSION The semi-empirical and integrated rate-law models facilitated reliable kinetic studies of NIF photodegradation as an example of AB(1Φ) unimolecular reactions. It allowed filling a gap in kinetic studies of drugs since, thus far, thermal first-order or a combination of first- and zero- order kinetic equations were generally applied for drug photoreactions in the literature. Also, a new reaction order, the "Φ-order", has been evidenced and proposed as a specific alternative for photodegradation kinetics.
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Affiliation(s)
- Wassila Maafi
- Leicester School of Pharmacy, De Montfort University, The Gateway, Leicester LE1 9BH, UK
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17
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Potential energy surfaces and quantum yields for photochromic diarylethene reactions. Molecules 2013; 18:5091-103. [PMID: 23644976 PMCID: PMC6270092 DOI: 10.3390/molecules18055091] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2013] [Revised: 04/18/2013] [Accepted: 04/19/2013] [Indexed: 11/16/2022] Open
Abstract
Photochromic diarylethenes (DAEs) are among the most promising molecular switching systems for future molecular electronics. Numerous derivatives have been synthesized recently, and experimental quantum yields (QYs) have been reported for two categories of them. Although the QY is one of the most important properties in various applications, it is also the most difficult property to predict before a molecule is actually synthesized. We have previously reported preliminary theoretical studies on what determines the QYs in both categories of DAE derivatives. Here, reflecting theoretical analyses of potential energy surfaces and recent experimental results, a rational explanation of the general guiding principle for QY design is presented for future molecular design.
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18
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Pariani G, Bianco A, Castagna R, Bertarelli C. Kinetics of Photochromic Conversion at the Solid State: Quantum Yield of Dithienylethene-Based Films. J Phys Chem A 2011; 115:12184-93. [DOI: 10.1021/jp207210p] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Giorgio Pariani
- Dipartimento di Chimica, Materiali e Ingegneria Chimica “G. Natta”, Politecnico di Milano, piazza L. da Vinci 32, 20133 Milano, Italy
- Istituto Nazionale di Astrofisica - Osservatorio Astronomico di Brera, via E. Bianchi 46, 23807 Merate, Italy
| | - Andrea Bianco
- Istituto Nazionale di Astrofisica - Osservatorio Astronomico di Brera, via E. Bianchi 46, 23807 Merate, Italy
| | - Rossella Castagna
- Dipartimento di Chimica, Materiali e Ingegneria Chimica “G. Natta”, Politecnico di Milano, piazza L. da Vinci 32, 20133 Milano, Italy
- Center for Nano Science and Technology @PoliMi, Istituto Italiano di Tecnologia, via G. Pascoli 70/3, 20133 Milano, Italy
| | - Chiara Bertarelli
- Dipartimento di Chimica, Materiali e Ingegneria Chimica “G. Natta”, Politecnico di Milano, piazza L. da Vinci 32, 20133 Milano, Italy
- Center for Nano Science and Technology @PoliMi, Istituto Italiano di Tecnologia, via G. Pascoli 70/3, 20133 Milano, Italy
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