1
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Barros CHN, Alfaro M, Costello C, Wang F, Sapre K, Rastogi S, Chiruvolu S, Connolly J, Topp EM. Effect of Atomic Layer Coating on the Stability of Solid Myoglobin Formulations. Mol Pharm 2023; 20:4086-4099. [PMID: 37466053 DOI: 10.1021/acs.molpharmaceut.3c00229] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 07/20/2023]
Abstract
The effects of atomic layer (ALC) coating on physical properties and storage stability were examined in solid powders containing myoglobin, a model protein. Powders containing myoglobin and mannitol (1:1 w/w) were prepared by lyophilization or spray drying and subjected to aluminum oxide or silicon oxide ALC coating. Uncoated samples of these powders as well as coated and uncoated samples of myoglobin as received served as controls. After preparation (t0), samples were analyzed for moisture content, reconstitution time, myoglobin secondary structure, crystallinity, and protein aggregate content. Samples were stored for 3 months (t3) under controlled conditions (53% RH, 40 °C) in both open and closed vials and then analyzed as above. At t3, the recovery of soluble native (i.e., monomeric) protein depended on formulation, coating type, and drying method and was up to 2-fold greater in coated samples than in uncoated controls. Promisingly, some samples with high recovery also showed low soluble aggregate content (<10%) at t3 and low total monomer loss; the latter was correlated to sample moisture content. Overall, the results demonstrate that ALC coatings can stabilize solid protein formulations during storage, providing benefits over uncoated controls.
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Affiliation(s)
- Caio H N Barros
- National Institution for Bioprocessing Research and Training (NIBRT), Dublin A94 X099, Ireland
| | - Manuel Alfaro
- National Institution for Bioprocessing Research and Training (NIBRT), Dublin A94 X099, Ireland
| | - Cormac Costello
- National Institution for Bioprocessing Research and Training (NIBRT), Dublin A94 X099, Ireland
| | - Fei Wang
- Applied Materials, Inc., Santa Clara, California 58039, United States
| | - Kedar Sapre
- Applied Materials, Inc., Santa Clara, California 58039, United States
| | - Suneel Rastogi
- Applied Materials, Inc., Santa Clara, California 58039, United States
| | | | - James Connolly
- Applied Materials, Inc., Santa Clara, California 58039, United States
| | - Elizabeth M Topp
- National Institution for Bioprocessing Research and Training (NIBRT), Dublin A94 X099, Ireland
- Department of Industrial and Physical Pharmacy, Purdue University, West Lafayette, Indiana 47907, United States
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2
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Sosa J, Berriel SN, Feit C, Currie TM, Shultz LR, Rudawski NG, Jurca T, Banerjee P. Release Rate Studies of 5-Aminosalacylic Acid Coated with Atomic Layer-Deposited Al 2O 3 and ZnO in an Acidic Environment. ACS APPLIED BIO MATERIALS 2023; 6:93-103. [PMID: 36515998 DOI: 10.1021/acsabm.2c00750] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
5-Aminosalicylic acid (5-ASA) is a first-line defense drug used to treat mild cases of inflammatory bowel disease. When administered orally, the active pharmaceutical ingredient is released throughout the gastrointestinal tract relieving chronic inflammation. However, delayed and targeted released systems for 5-ASA to achieve optimal dose volumes in acidic environments remain a challenge. Here, we demonstrate the application of atomic layer deposition (ALD) as a technique to synthesize nanoscale coatings on 5-ASA to control its release in acidic media. ALD Al2O3 (38.0 nm) and ZnO (24.7 nm) films were deposited on 1 g batch powders of 5-ASA in a rotatory thermal ALD system. Fourier transform infrared spectroscopy, scanning electron microscopy, and scanning/transmission electron microscopy establish the interfacial chemistry and conformal nature of ALD coating over the 5-ASA particles. While Al2O3 forms a sharp interface with 5-ASA, ZnO appears to diffuse inside 5-ASA. The release of 5-ASA is studied in a pH 4 solution via UV-vis spectroscopy. Dynamic stirring, mimicking gut peristalsis, causes mechanical attrition of the Al2O3-coated particles, thereby releasing 5-ASA. However, under static conditions lasting 5000 s, the Al2O3-coated particles release only 17.5% 5-ASA compared to 100% release with the ZnO coating. Quartz crystal microbalance-based etch studies confirm the stability of Al2O3 in pH 4 media, where the ZnO films etch 41× faster than Al2O3. Such results are significant in achieving a nanoscale coating-based drug delivery system for 5-ASA with controlled release in acidic environments.
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Affiliation(s)
- Jaynlynn Sosa
- NanoScience and Technology Center, University of Central Florida, Orlando, Florida 32826, United States
| | - S Novia Berriel
- Department of Materials Science and Engineering, University of Central Florida, Orlando, Florida 32816, United States
| | - Corbin Feit
- Department of Materials Science and Engineering, University of Central Florida, Orlando, Florida 32816, United States
| | - Taylor M Currie
- Department of Chemistry, University of Central Florida, Orlando, Florida 32816, United States
| | - Lorianne R Shultz
- Department of Chemistry, University of Central Florida, Orlando, Florida 32816, United States
| | - Nicholas G Rudawski
- Research Service Centers, University of Florida, Gainesville, Florida 32611, United States
| | - Titel Jurca
- NanoScience and Technology Center, University of Central Florida, Orlando, Florida 32826, United States.,Department of Chemistry, University of Central Florida, Orlando, Florida 32816, United States.,REACT Faculty Cluster, University of Central Florida, Orlando, Florida 32816, United States
| | - Parag Banerjee
- NanoScience and Technology Center, University of Central Florida, Orlando, Florida 32826, United States.,Department of Materials Science and Engineering, University of Central Florida, Orlando, Florida 32816, United States.,REACT Faculty Cluster, University of Central Florida, Orlando, Florida 32816, United States.,Florida Solar Energy Center, University of Central Florida, Orlando, Florida 32816, United States
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3
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Moseson DE, Benson EG, Cao Z, Bhalla S, Wang F, Wang M, Zheng K, Narwankar PK, Simpson GJ, Taylor LS. Impact of Aluminum Oxide Nanocoating on Drug Release from Amorphous Solid Dispersion Particles. Mol Pharm 2023; 20:593-605. [PMID: 36346665 DOI: 10.1021/acs.molpharmaceut.2c00818] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Atomic layer coating (ALC) is emerging as a particle engineering strategy to inhibit surface crystallization of amorphous solid dispersions (ASDs). In this study, we turn our attention to evaluating drug release behavior from ALC-coated ASDs, and begin to develop a mechanistic framework. Posaconazole/hydroxypropyl methylcellulose acetate succinate was used as a model system at both 25% and 50% drug loadings. ALC-coatings of aluminum oxide up to 40 nm were evaluated for water sorption kinetics and dissolution performance under a range of pH conditions. Scanning electron microscopy with energy dispersive X-ray analysis was used to investigate the microstructure of partially released ASD particles. Coating thickness and defect density (inferred from deposition rates) were found to impact water sorption kinetics. Despite reduced water sorption kinetics, the presence of a coating was not found to impact dissolution rates under conditions where rapid drug release was observed. Under slower releasing conditions, underlying matrix crystallization was reduced by the coating, enabling greater levels of drug release. These results demonstrate that water was able to penetrate through the ALC coating, hydrating the amorphous solid, which can initiate dissolution of drug and/or polymer (depending on pH conditions). Swelling of the ASD substrate subsequently occurs, disrupting and cracking the coating, which serves to facilitate rapid drug release. Water sorption kinetics are highlighted as a potential predictive tool to investigate the coating quality and its potential impact on dissolution performance. This study has implications for formulation design and evaluation of ALC-coated ASD particles.
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Affiliation(s)
- Dana E Moseson
- Department of Industrial and Physical Pharmacy, College of Pharmacy, Purdue University, West Lafayette, Indiana 47907, United States
| | - Emily G Benson
- Department of Industrial and Physical Pharmacy, College of Pharmacy, Purdue University, West Lafayette, Indiana 47907, United States
| | - Ziyi Cao
- Department of Chemistry, College of Science, Purdue University, West Lafayette, Indiana 47907, United States
| | - Shradha Bhalla
- Department of Industrial and Physical Pharmacy, College of Pharmacy, Purdue University, West Lafayette, Indiana 47907, United States
| | - Fei Wang
- Applied Materials, Inc., 3100 Bowers Ave, Santa Clara, California 95054, United States
| | - Miaojun Wang
- Applied Materials, Inc., 3100 Bowers Ave, Santa Clara, California 95054, United States
| | - Kai Zheng
- Applied Materials, Inc., 3100 Bowers Ave, Santa Clara, California 95054, United States
| | - Pravin K Narwankar
- Applied Materials, Inc., 3100 Bowers Ave, Santa Clara, California 95054, United States
| | - Garth J Simpson
- Department of Chemistry, College of Science, Purdue University, West Lafayette, Indiana 47907, United States
| | - Lynne S Taylor
- Department of Industrial and Physical Pharmacy, College of Pharmacy, Purdue University, West Lafayette, Indiana 47907, United States
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4
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Moseson DE, Benson EG, Nguyen HT, Wang F, Wang M, Zheng K, Narwankar PK, Taylor LS. Atomic Layer Coating to Inhibit Surface Crystallization of Amorphous Pharmaceutical Powders. ACS APPLIED MATERIALS & INTERFACES 2022; 14:40698-40710. [PMID: 36054111 DOI: 10.1021/acsami.2c12666] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/15/2023]
Abstract
Preventing crystallization is a primary concern when developing amorphous drug formulations. Recently, atomic layer coatings (ALCs) of aluminum oxide demonstrated crystallization inhibition of high drug loading amorphous solid dispersions (ASDs) for over 2 years. The goal of the current study was to probe the breadth and mechanisms of this exciting finding through multiple drug/polymer model systems, as well as particle and coating attributes. The model ASD systems selected provide for a range of hygroscopicity and chemical functional groups, which may contribute to the crystallization inhibition effect of the ALC coatings. Atomic layer coating was performed to apply a 5-25 nm layer of aluminum oxide or zinc oxide onto ASD particles, which imparted enhanced micromeritic properties, namely, reduced agglomeration and improved powder flowability. ASD particles were stored at 40 °C and a selected relative humidity level between 31 and 75%. Crystallization was monitored by X-ray powder diffraction and scanning electron microscopy (SEM) up to 48 weeks. Crystallization was observable by SEM within 1-2 weeks for all uncoated samples. After ALC, crystallization was effectively delayed or completely inhibited in some systems up to 48 weeks. The delay achieved was demonstrated regardless of polymer hygroscopicity, presence or absence of hydroxyl functional groups in drugs and/or polymers, particle size, or coating properties. The crystallization inhibition effect is attributed primarily to decreased surface molecular mobility. ALC has the potential to be a scalable strategy to enhance the physical stability of ASD systems to enable high drug loading and enhanced robustness to temperature or relative humidity excursions.
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Affiliation(s)
- Dana E Moseson
- Department of Industrial and Physical Pharmacy, College of Pharmacy, Purdue University, West Lafayette, Indiana 47907, United States
| | - Emily G Benson
- Department of Industrial and Physical Pharmacy, College of Pharmacy, Purdue University, West Lafayette, Indiana 47907, United States
| | - Hanh Thuy Nguyen
- Department of Industrial and Physical Pharmacy, College of Pharmacy, Purdue University, West Lafayette, Indiana 47907, United States
| | - Fei Wang
- Applied Materials, Inc., 3100 Bowers Avenue, Santa Clara, California 95054, United States
| | - Miaojun Wang
- Applied Materials, Inc., 3100 Bowers Avenue, Santa Clara, California 95054, United States
| | - Kai Zheng
- Applied Materials, Inc., 3100 Bowers Avenue, Santa Clara, California 95054, United States
| | - Pravin K Narwankar
- Applied Materials, Inc., 3100 Bowers Avenue, Santa Clara, California 95054, United States
| | - Lynne S Taylor
- Department of Industrial and Physical Pharmacy, College of Pharmacy, Purdue University, West Lafayette, Indiana 47907, United States
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5
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Surface nanocoating of high drug-loading spray-dried amorphous solid dispersions by atomic layer coating: Excellent physical stability under accelerated storage conditions for two years. Int J Pharm 2022; 620:121747. [DOI: 10.1016/j.ijpharm.2022.121747] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2022] [Revised: 04/05/2022] [Accepted: 04/09/2022] [Indexed: 12/24/2022]
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6
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La Zara D, Sun F, Zhang F, Franek F, Balogh Sivars K, Horndahl J, Bates S, Brännström M, Ewing P, Quayle MJ, Petersson G, Folestad S, van Ommen JR. Controlled Pulmonary Delivery of Carrier-Free Budesonide Dry Powder by Atomic Layer Deposition. ACS NANO 2021; 15:6684-6698. [PMID: 33769805 PMCID: PMC8155342 DOI: 10.1021/acsnano.0c10040] [Citation(s) in RCA: 19] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/01/2020] [Accepted: 03/22/2021] [Indexed: 06/12/2023]
Abstract
Ideal controlled pulmonary drug delivery systems provide sustained release by retarding lung clearance mechanisms and efficient lung deposition to maintain therapeutic concentrations over prolonged time. Here, we use atomic layer deposition (ALD) to simultaneously tailor the release and aerosolization properties of inhaled drug particles without the need for lactose carrier. In particular, we deposit uniform nanoscale oxide ceramic films, such as Al2O3, TiO2, and SiO2, on micronized budesonide particles, a common active pharmaceutical ingredient for the treatment of respiratory diseases. In vitro dissolution and ex vivo isolated perfused rat lung tests demonstrate dramatically slowed release with increasing nanofilm thickness, regardless of the nature of the material. Ex situ transmission electron microscopy at various stages during dissolution unravels mostly intact nanofilms, suggesting that the release mechanism mainly involves the transport of dissolution media through the ALD films. Furthermore, in vitro aerosolization testing by fast screening impactor shows a ∼2-fold increase in fine particle fraction (FPF) for each ALD-coated budesonide formulation after 10 ALD process cycles, also applying very low patient inspiratory pressures. The higher FPFs after the ALD process are attributed to the reduction in the interparticle force arising from the ceramic surfaces, as evidenced by atomic force microscopy measurements. Finally, cell viability, cytokine release, and tissue morphology analyses verify a safe and efficacious use of ALD-coated budesonide particles at the cellular level. Therefore, surface nanoengineering by ALD is highly promising in providing the next generation of inhaled formulations with tailored characteristics of drug release and lung deposition, thereby enhancing controlled pulmonary delivery opportunities.
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Affiliation(s)
- Damiano La Zara
- Department
of Chemical Engineering, Delft University
of Technology, Van der Maasweg 9, Delft, 2629HZ, The Netherlands
| | - Feilong Sun
- Department
of Chemical Engineering, Delft University
of Technology, Van der Maasweg 9, Delft, 2629HZ, The Netherlands
| | - Fuweng Zhang
- Department
of Chemical Engineering, Delft University
of Technology, Van der Maasweg 9, Delft, 2629HZ, The Netherlands
| | - Frans Franek
- Advanced
Drug Delivery, Pharmaceutical Sciences, R&D, AstraZeneca, Gothenburg, Sweden
| | - Kinga Balogh Sivars
- Clinical
Testing and Precision Medicine, Global Procurement, Operations, AstraZeneca, Gothenburg, Sweden
| | - Jenny Horndahl
- Bioscience
COPD/IPF, Research and Early Development, Respiratory & Immunology, BioPharmaceuticals R&D, AstraZeneca, Gothenburg, Sweden
| | - Stephanie Bates
- Functional
and Mechanistic Safety, Clinical Pharmacology
and Safety Sciences, R&D, AstraZeneca, Cambridge U.K.
| | - Marie Brännström
- Drug
Metabolism and Pharmacokinetics, Research and Early Development, Respiratory & Immunology, BioPharmaceuticals R&D,
AstraZeneca, Gothenburg, Sweden
| | - Pär Ewing
- Drug
Metabolism and Pharmacokinetics, Research and Early Development, Respiratory & Immunology, BioPharmaceuticals R&D,
AstraZeneca, Gothenburg, Sweden
| | - Michael J. Quayle
- New Modalities
and Parenteral Development, Pharmaceutical Technology & Development, Operations, AstraZeneca, Gothenburg, Sweden
| | - Gunilla Petersson
- Innovation
Strategy and External Liaison, Pharmaceutical Technology & Development, Operations, AstraZeneca, Gothenburg, Sweden
| | - Staffan Folestad
- Innovation
Strategy and External Liaison, Pharmaceutical Technology & Development, Operations, AstraZeneca, Gothenburg, Sweden
| | - J. Ruud van Ommen
- Department
of Chemical Engineering, Delft University
of Technology, Van der Maasweg 9, Delft, 2629HZ, The Netherlands
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7
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Hu Y, Lu J, Feng H. Surface modification and functionalization of powder materials by atomic layer deposition: a review. RSC Adv 2021; 11:11918-11942. [PMID: 35423751 PMCID: PMC8697040 DOI: 10.1039/d1ra00326g] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2021] [Accepted: 03/05/2021] [Indexed: 11/21/2022] Open
Abstract
Powder materials are a class of industrial materials with many important applications. In some circumstances, surface modification and functionalization of these materials are essential for achieving or enhancing their expected performances. However, effective and precise surface modification of powder materials remains a challenge due to a series of problems such as high surface area, diffusion limitation, and particle agglomeration. Atomic layer deposition (ALD) is a cutting-edge thin film coating technology traditionally used in the semiconductor industry. ALD enables layer by layer thin film growth by alternating saturated surface reactions between the gaseous precursors and the substrate. The self-limiting nature of ALD surface reaction offers angstrom level thickness control as well as exceptional film conformality on complex structures. With these advantages, ALD has become a powerful tool to effectively fabricate powder materials for applications in many areas other than microelectronics. This review focuses on the unique capability of ALD in surface engineering of powder materials, including recent advances in the design of ALD reactors for powder fabrication, and applications of ALD in areas such as stabilization of particles, catalysts, energetic materials, batteries, wave absorbing materials and medicine. We intend to show the versatility and efficacy of ALD in fabricating various kinds of powder materials, and help the readers gain insights into the principles, methods, and unique effects of powder fabrication by ALD.
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Affiliation(s)
- Yiyun Hu
- Science and Technology on Combustion and Explosion Laboratory, Xi'an Modern Chemistry Research Institute 168 E. Zhangba Road Xi'an 710065 Shanxi PR China
- Laboratory of Material Surface Engineering and Nanofabrication, Xi'an Modern Chemistry Research Institute 168 E. Zhangba Road Xi'an 710065 Shanxi PR China
| | - Jian Lu
- State Key Laboratory of Fluorine and Nitrogen Chemicals, Xi'an Modern Chemistry Research Institute 168 E. Zhangba Road Xi'an 710065 Shanxi PR China
| | - Hao Feng
- Science and Technology on Combustion and Explosion Laboratory, Xi'an Modern Chemistry Research Institute 168 E. Zhangba Road Xi'an 710065 Shanxi PR China
- Laboratory of Material Surface Engineering and Nanofabrication, Xi'an Modern Chemistry Research Institute 168 E. Zhangba Road Xi'an 710065 Shanxi PR China
- State Key Laboratory of Fluorine and Nitrogen Chemicals, Xi'an Modern Chemistry Research Institute 168 E. Zhangba Road Xi'an 710065 Shanxi PR China
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8
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Knemeyer K, Baumgarten R, Ingale P, Naumann d'Alnoncourt R, Driess M, Rosowski F. Toolbox for atomic layer deposition process development on high surface area powders. THE REVIEW OF SCIENTIFIC INSTRUMENTS 2021; 92:025115. [PMID: 33648082 DOI: 10.1063/5.0037844] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/16/2020] [Accepted: 01/29/2021] [Indexed: 06/12/2023]
Abstract
Atomic layer deposition (ALD) is an industrially applied technique for thin film deposition. The vast majority of processes target flat substrates rather than powders. For ALD on powders, new processes are needed, as different reaction conditions are required. Here, two setups are described in detail, which enhance the ALD process development for powders. The first setup described is capable of directly measuring the vapor pressure of a given precursor by a capacitance diaphragm gauge. Promising precursors can be pre-selected, and suitable precursor saturation temperatures can be determined. The second setup consists of four parallel reactors with individual temperature zones to screen the optimal ALD temperature window in a time efficient way. Identifying the precursor saturation temperature beforehand and subsequently performing the first ALD half cycle in the parallel setup at four different reactor temperatures simultaneously will drastically reduce process development times. Validation of both setups is shown for the well-known ALD precursors, trimethylaluminum to deposit aluminum oxide and diethyl zinc to deposit zinc oxide, both on amorphous silica powder.
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Affiliation(s)
- K Knemeyer
- BasCat-UniCat BASF JointLab, Technische Universität Berlin, Hardenbergstraße 36, 10623 Berlin, Germany
| | - R Baumgarten
- BasCat-UniCat BASF JointLab, Technische Universität Berlin, Hardenbergstraße 36, 10623 Berlin, Germany
| | - P Ingale
- BasCat-UniCat BASF JointLab, Technische Universität Berlin, Hardenbergstraße 36, 10623 Berlin, Germany
| | - R Naumann d'Alnoncourt
- BasCat-UniCat BASF JointLab, Technische Universität Berlin, Hardenbergstraße 36, 10623 Berlin, Germany
| | - M Driess
- BasCat-UniCat BASF JointLab, Technische Universität Berlin, Hardenbergstraße 36, 10623 Berlin, Germany
| | - F Rosowski
- BasCat-UniCat BASF JointLab, Technische Universität Berlin, Hardenbergstraße 36, 10623 Berlin, Germany
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9
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Hirschberg C, Jensen NS, Boetker J, Madsen AØ, Kääriäinen TO, Kääriäinen ML, Hoppu P, George SM, Murtomaa M, Sun CC, Risbo J, Rantanen J. Improving Powder Characteristics by Surface Modification Using Atomic Layer Deposition. Org Process Res Dev 2019. [DOI: 10.1021/acs.oprd.9b00247] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Cosima Hirschberg
- Department of Pharmacy, University of Copenhagen, Universitetsparken 2, 2100 Copenhagen, Denmark
| | - Nikolaj Sølvkær Jensen
- Department of Pharmacy, University of Copenhagen, Universitetsparken 2, 2100 Copenhagen, Denmark
| | - Johan Boetker
- Department of Pharmacy, University of Copenhagen, Universitetsparken 2, 2100 Copenhagen, Denmark
| | - Anders Østergaard Madsen
- Department of Pharmacy, University of Copenhagen, Universitetsparken 2, 2100 Copenhagen, Denmark
| | - Tommi O. Kääriäinen
- NovaldMedical Ltd Oy, Telkäntie 5, 82500 Kitee, Finland
- Department of Chemistry, University of Colorado, Boulder, Colorado 80309, United States
| | | | - Pekka Hoppu
- NovaldMedical Ltd Oy, Telkäntie 5, 82500 Kitee, Finland
| | - Steven M. George
- Department of Chemistry, University of Colorado, Boulder, Colorado 80309, United States
| | - Matti Murtomaa
- Department of Physics and Astronomy, University of Turku, 20014 Turku, Finland
| | - Changquan Calvin Sun
- Department of Pharmaceutics, University of Minnesota, 308 Harvard St. SE, Minneapolis, Minnesota 55455, United States
| | - Jens Risbo
- Department of Food Sciences, University of Copenhagen, Rolighedsvej 30, 1958 Frederiksberg, Denmark
| | - Jukka Rantanen
- Department of Pharmacy, University of Copenhagen, Universitetsparken 2, 2100 Copenhagen, Denmark
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