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Zhang J, Khanal D, Banaszak Holl MM. Applications of AFM-IR for drug delivery vector characterization: infrared, thermal, and mechanical characterization at the nanoscale. Adv Drug Deliv Rev 2023; 192:114646. [PMID: 36521685 DOI: 10.1016/j.addr.2022.114646] [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] [Received: 03/18/2022] [Revised: 11/15/2022] [Accepted: 12/04/2022] [Indexed: 12/15/2022]
Abstract
The development of effective drug delivery systems requires in-depth characterization of the micro- or nanostructure of the material vectors with high spatial resolution, resulting in a deep understanding of the design-function relationship and maximum therapeutic efficacy. Atomic force microscopy-infrared spectroscopy (AFM-IR) combines the high spatial resolution of AFM and the capabilities of IR spectroscopy to identify chemical composition and it has emerged as a powerful tool for the detailed characterization of a drug delivery system at the nanoscale. In addition, the instruments also allow thermal and mechanical evaluation at the nanoscale. In this review, we highlight the applications of AFM-IR in various drug delivery systems, including polymer-based carriers, lipid-contained nanocarriers, and metal-based nanocarriers. The existing challenges as well as the future perspectives for the application of AFM-IR for drug delivery vector characterization are also discussed.
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Affiliation(s)
- Jing Zhang
- Department of Chemical & Biological Engineering, Monash University, Clayton, Victoria 3800, Australia.
| | - Dipesh Khanal
- Advanced Drug Delivery Group, School of Pharmacy, Faculty of Medicine and Health, The University of Sydney, NSW 2006, Australia; The University of Sydney, Sydney Nano Institute, Sydney, New South Wales 2006, Australia.
| | - Mark M Banaszak Holl
- Department of Chemical & Biological Engineering, Monash University, Clayton, Victoria 3800, Australia; Department of Mechanial and Materials Engineering, School of Engineering University of Alabama at Birmingham, Birmingham, AL 35294 USA; Division of Pulmonology, Allergy, and Critical Care Medicine, Heersink Medical School, University of Alabama at Birmingham, Birmingham, AL 35294 USA.
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2
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Chen C, Chen C, Li Y, Gu R, Yan X. Characterization of lipid-based nanomedicines at the single-particle level. FUNDAMENTAL RESEARCH 2022. [DOI: 10.1016/j.fmre.2022.09.011] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022] Open
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3
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Probing both sides of the story. Proc Natl Acad Sci U S A 2022; 119:e2212419119. [PMID: 36070345 PMCID: PMC9499575 DOI: 10.1073/pnas.2212419119] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/04/2022] Open
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4
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Dou T, Zens C, Schröder K, Jiang Y, Makarov AA, Kupfer S, Kurouski D. Solid-to-Liposome Conformational Transition of Phosphatidylcholine and Phosphatidylserine Probed by Atomic Force Microscopy, Infrared Spectroscopy, and Density Functional Theory Calculations. Anal Chem 2022; 94:13243-13249. [PMID: 36107722 PMCID: PMC10405298 DOI: 10.1021/acs.analchem.2c03061] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Liposomes are emerging therapeutic formulations for site-specific delivery of chemotherapeutic drugs. The efficiency and selectivity of drug delivery by these carriers largely rely on their surface properties, shape, and size. There is a growing demand for analytical approaches that can be used for structural and morphological characterization of liposomes at the single-vesicle level. AFM-IR is a modern optical nanoscopic technique that combines the advantages of scanning probe microscopy and infrared spectroscopy. Our findings show that AFM-IR can be used to probe conformational changes in phospholipids that take place upon their assembly into liposomes. Such conclusions can be made based on the corresponding changes in intensities of the lipid vibrational bands as the molecules transition from a solid state into large unilamellar vesicles (LUVs). This spectroscopic analysis of LUV formation together with density functional theory calculations also reveals the extent to which the molecular conformation and local environment of the functional groups alter the AFM-IR spectra of phospholipids. Using melittin as a test protein, we also examined the extent to which LUVs can be used for protein internalization. We found that melittin enters LUVs nearly instantaneously, which protects it from possible structural modifications that are caused by a changing environment. This foundational work empowers AFM-IR analysis of liposomes and opens new avenues for determination of the molecular mechanisms of liposome-drug interactions.
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Affiliation(s)
- Tianyi Dou
- Department of Biochemistry and Biophysics, Texas A&M University, College Station, Texas 77843, United States
| | - Clara Zens
- Institute of Physical Chemistry, Friedrich Schiller University Jena, Helmholtzweg 4, 07743 Jena, Germany
| | - Katrin Schröder
- Institute of Physical Chemistry, Friedrich Schiller University Jena, Helmholtzweg 4, 07743 Jena, Germany
| | - Yuan Jiang
- Merck & Company Inc., MRL, Analytical Research & Development, Boston, Massachusetts 02115, United States
| | - Alexey A. Makarov
- Merck & Company Inc., MRL, Analytical Research & Development, Boston, Massachusetts 02115, United States
| | - Stephan Kupfer
- Institute of Physical Chemistry, Friedrich Schiller University Jena, Helmholtzweg 4, 07743 Jena, Germany
| | - Dmitry Kurouski
- Department of Biochemistry and Biophysics, Texas A&M University, College Station, Texas 77843, United States
- Department of Biomedical Engineering, Texas A&M University, College Station, Texas 77843, United States
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5
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Shen Y, Zhu C, Wei Y, Chen H, Wu Z, Ye Y, Han DM. Engineering of Portable Smartphone Integrated with Liposome-Encapsulated Curcumin for Onsite Visual Ratiometric Fluorescence Imaging of Hypochlorite. Chemistry 2022; 28:e202200263. [PMID: 35233854 DOI: 10.1002/chem.202200263] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2022] [Indexed: 12/18/2022]
Abstract
Precisely onsite monitoring of hypochlorite (ClO- ) is of great significance to guide its rational use, reducing/avoiding its potential threat toward food safety and human health. Considering ClO- could quench fluorescence of curcumin (CCM) by oxidizing the o-methoxyphenol of CCM into benzoquinone, a portable ratiometric fluorescence sensor integrated with smartphone was designed for realizing the visual point-of-care testing (POCT) of ClO- . The amphiphilic phospholipid polymer was used as carrier to wrap curcumin, forming a novel liposome-encapsulated CCM, which provided a scaffold to bind with [Ru(bpy)3 ]2+ through electrostatic interaction, thus assembling [Ru(bpy)3 ]2+ -functionalized liposome-encapsulated CCM ([Ru(bpy)3 ]2+ @CCM-NPs). Further integrated with smartphone, visual imaging of [Ru(bpy)3 ]2+ @CCM-NPs could be achieved and the accurate onsite detection of ClO- could be realized with a detection limit of 66.31 nM and a linear range of 0.2210 to 80.0 μM. In addition, the sensor could monitor ClO- in real samples with an onsite detection time of ∼154.0 s.
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Affiliation(s)
- Yizhong Shen
- School of Food & Biological Engineering, Key Laboratory for Agricultural Products Processing of Anhui Province, Hefei University of Technology, Hefei, 230009, China
| | - Chunlei Zhu
- School of Food & Biological Engineering, Key Laboratory for Agricultural Products Processing of Anhui Province, Hefei University of Technology, Hefei, 230009, China
| | - Yunlong Wei
- School of Food & Biological Engineering, Key Laboratory for Agricultural Products Processing of Anhui Province, Hefei University of Technology, Hefei, 230009, China
| | - Huanhuan Chen
- School of Food & Biological Engineering, Key Laboratory for Agricultural Products Processing of Anhui Province, Hefei University of Technology, Hefei, 230009, China
| | - Zeyu Wu
- School of Food & Biological Engineering, Key Laboratory for Agricultural Products Processing of Anhui Province, Hefei University of Technology, Hefei, 230009, China
| | - Yingwang Ye
- School of Food & Biological Engineering, Key Laboratory for Agricultural Products Processing of Anhui Province, Hefei University of Technology, Hefei, 230009, China
| | - De-Man Han
- Engineering Research Center of Recycling & Comprehensive Utilization of Pharmaceutical and Chemical Waste of Zhejiang Province, Taizhou University of Technology, Jiaojiang, 318000, China
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6
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Goh CF, Lane ME. Advanced structural characterisation of pharmaceuticals using nano-thermal analysis (nano-TA). Adv Drug Deliv Rev 2022; 180:114077. [PMID: 34896130 DOI: 10.1016/j.addr.2021.114077] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2021] [Revised: 11/12/2021] [Accepted: 12/02/2021] [Indexed: 12/17/2022]
Abstract
The production of drug delivery systems fabricated at the nano scale comes with the challenges of identifying reliable characterisation tools, especially for solid dosage forms. A full understanding of physicochemical properties of solid-state systems at a high spatial resolution is essential to monitor their manufacturability, processability, performance (dissolution) and stability. Nano-thermal analysis (nano-TA), a hybrid of atomic force microscopy (AFM) and thermal analysis, has emerged as a solution to address the need for complete characterisation of samples with surface heterogeneity. Nano-TA provides not only physical information using conventional AFM but also the thermal behaviour of these systems as an additional chemical dimension. In this review, the principles and techniques of nano-TA are discussed with emphasis on recent pharmaceutical applications. Building on nano-TA, the combination of this approach with infrared spectroscopic analysis is briefly introduced. The challenges and considerations for future development of nano-TA characterisation are also outlined.
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Affiliation(s)
- Choon Fu Goh
- Discipline of Pharmaceutical Technology, School of Pharmaceutical Sciences, Universiti Sains Malaysia, 11800 Minden, Penang, Malaysia.
| | - Majella E Lane
- Department of Pharmaceutics, UCL School of Pharmacy, 29-39 Brunswick Square, London WC1N 1AX, United Kingdom.
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Cheng Z, Li Y, Wang K, Zhu X, Tharkar P, Shu W, Zhang T, Zeng S, Zhu L, Murray M, Chrzanowski W, Zhou F. Compritol solid lipid nanoparticle formulations enhance the protective effect of betulinic acid derivatives in human Müller cells against oxidative injury. Exp Eye Res 2021; 215:108906. [PMID: 34953864 DOI: 10.1016/j.exer.2021.108906] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2021] [Revised: 11/26/2021] [Accepted: 12/20/2021] [Indexed: 02/05/2023]
Abstract
Müller cells maintain homeostatic functions in the retina. Their dysfunction leads to irreversible retinal diseases. Oxidative injury is a leading cause of retinal cytotoxicity. Our previous studies reported several betulinic acid (BA) derivatives can protect Müller cells from oxidative injury but achieving pharmacologically effective concentrations in the Müller cells could be a limitation. To optimise cellular delivery, we encapsulated the BA analogues H3, H5 and H7 into the clinically approved Compritol 888 and HD5 ATO solid lipid nanoparticles (SLNs) using the micro-emulsion method. The cytoprotective effects of these SLN-formulations were determined in human MIO-M1 cells. We found cytoprotection by H3 and H5 SLN-formulations was significantly enhanced, which was evident at concentrations much lower than those required with the free agents. Both SLN-formulations prolonged the duration of action of these agents. The most effective agent H5 delivered in 888 ATO SLNs attenuated glutamate-induced ROS formation and the associated necrosis in MIO-M1 cells. Overall, SLNs have emerged as promising delivery carriers for BA derivatives enhancing their protective effects against oxidative injury in human Müller cells. Our study is the first to show SLNs can be a viable route to delivery agents with improved efficacy and stability into human Müller cells favoring the treatment/prevention of retinal diseases.
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Affiliation(s)
- Zhengqi Cheng
- Sydney Pharmacy School, The University of Sydney, NSW, 2006, Australia; Bioland Laboratory, Guangzhou Regenerative Medicine and Health Guangdong Laboratory, Guangzhou, Guangdong, China; Guangzhou Institutes of Biomedicine and Health, Chinese Academy of Sciences, Guangzhou, Guangdong, China
| | - Yue Li
- Sydney Pharmacy School, The University of Sydney, NSW, 2006, Australia
| | - Ke Wang
- Key Laboratory of Nuclear Medicine, Ministry of Health, Jiangsu Key Laboratory of Molecular Nuclear Medicine, Jiangsu Institute of Nuclear Medicine, Wuxi, Jiangsu, China
| | - Xue Zhu
- Key Laboratory of Nuclear Medicine, Ministry of Health, Jiangsu Key Laboratory of Molecular Nuclear Medicine, Jiangsu Institute of Nuclear Medicine, Wuxi, Jiangsu, China
| | - Priyanka Tharkar
- Sydney Pharmacy School, The University of Sydney, NSW, 2006, Australia
| | - Wenying Shu
- Sydney Pharmacy School, The University of Sydney, NSW, 2006, Australia; Department of Pharmacy, Affiliated Cancer Hospital & Institute of Guangzhou Medical University, Guangdong Province, 511400, China
| | - Ting Zhang
- Save Sight Institute, The University of Sydney, Sydney, NSW, 2000, Australia; State Key Laboratory of Biotherapy and Cancer Center, Collaborative Innovation Center for Biotherapy, West China Hospital, Sichuan University, Chengdu, China
| | - Shaoxue Zeng
- Save Sight Institute, The University of Sydney, Sydney, NSW, 2000, Australia
| | - Ling Zhu
- Save Sight Institute, The University of Sydney, Sydney, NSW, 2000, Australia
| | - Michael Murray
- Sydney Pharmacy School, The University of Sydney, NSW, 2006, Australia
| | - Wojciech Chrzanowski
- Sydney Pharmacy School, The University of Sydney, NSW, 2006, Australia; The University of Sydney, Sydney Nano Institute, Camperdown, NSW, 2006, Australia
| | - Fanfan Zhou
- Sydney Pharmacy School, The University of Sydney, NSW, 2006, Australia.
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Zhang Y, Wu W, Zhang J, Li Z, Ma H, Zhao Z. Facile Method for Specifically Sensing Sphingomyelinase in Cells and Human Urine Based on a Ratiometric Fluorescent Nanoliposome Probe. Anal Chem 2021; 93:11775-11784. [PMID: 34412477 DOI: 10.1021/acs.analchem.1c02197] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Sphingomyelinase (SMase) is closely related to diseases like Niemann-Pick disease and atherosclerosis, and the development of a simple method for the assay of SMase activity is very useful to screen new potential inhibitors or stimulators of SMase or biomarkers of disease. Fluorophore-encapsulated nanoliposomes (FENs) are emerging as a new fluorescent probe for sensing the enzymatic activity. In this work, two fluorochromes (cy7 and IR780) were encapsulated into the liposome of sphingomyelin, and therefore, a sphingomyelin-based ratiometric FEN probe for the SMase activity assay was constructed. The probe shows high selectivity and sensitivity to acid SMase with a detection limit of 4.8 × 10-4 U/mL. Sphingomyelin is the natural substrate of SMase; therefore, the probe has native ability for all kinds of SMase activity assays. Moreover, the probe has been successfully applied to the analysis of acid SMase activity in cells and urine samples. As far as we know, this is the first example of a nanoliposome fluorescence method for assaying acid SMase, and the method is biocompatible and much simpler than the existing ones, which might provide a new strategy for developing new methods for other important esterases.
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Affiliation(s)
- Yangyang Zhang
- Beijing National Laboratory for Molecular Sciences, Key Laboratory of Analytical Chemistry for Living Biosystems, Institute of Chemistry Chinese Academy of Sciences, Beijing 100190, China.,University of Chinese Academy of Sciences, Beijing 100049, China
| | - Wenjing Wu
- Beijing National Laboratory for Molecular Sciences, Key Laboratory of Analytical Chemistry for Living Biosystems, Institute of Chemistry Chinese Academy of Sciences, Beijing 100190, China.,University of Chinese Academy of Sciences, Beijing 100049, China
| | - Junjie Zhang
- College of Life Sciences, Beijing Normal University, Beijing 100875, China
| | - Zhao Li
- Department of Hepatobiliary Surgery, Peking University People's Hospital, Beijing 100044, China
| | - Huimin Ma
- Beijing National Laboratory for Molecular Sciences, Key Laboratory of Analytical Chemistry for Living Biosystems, Institute of Chemistry Chinese Academy of Sciences, Beijing 100190, China.,University of Chinese Academy of Sciences, Beijing 100049, China
| | - Zhenwen Zhao
- Beijing National Laboratory for Molecular Sciences, Key Laboratory of Analytical Chemistry for Living Biosystems, Institute of Chemistry Chinese Academy of Sciences, Beijing 100190, China.,University of Chinese Academy of Sciences, Beijing 100049, China
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Khatib I, Ke WR, Cipolla D, Chan HK. Storage stability of inhalable, controlled-release powder formulations of ciprofloxacin nanocrystal-containing liposomes. Int J Pharm 2021; 605:120809. [PMID: 34144139 DOI: 10.1016/j.ijpharm.2021.120809] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2021] [Revised: 06/07/2021] [Accepted: 06/13/2021] [Indexed: 10/21/2022]
Abstract
Novel inhalable and controlled release powder formulations of ciprofloxacin nanocrystals inside liposomes (CNL) were recently developed. In the present study, the storage stability of CNL powders consisting of lyoprotectant (i.e. sucrose or lactose), lipids, ciprofloxacin (CIP), and magnesium stearate or isoleucine was investigated. These powders were produced by spray drying, collected in a dry box at <15% relative humidity (RH), then stored at room temperature and either 4 or 20 %RH. Liposomal integrity, CIP encapsulation efficiency (EE), in vitro drug release (IVR), aerosol performance, and solid-state properties were examined over six months. Sucrose CNL powder exhibited consistent liposomal integrity, aerosol performance, and controlled release of CIP over six months of storage at 4 %RH. However, storage of the powder at 20 %RH for the same period caused sucrose crystallization and consequently a significant drop in EE and aerosol performance (p-values < 0.05), along with the IVR of CIP becoming similar to that of the non-crystalline CIP liposomal dispersions (f2 > 50). Lactose CNL maintained superior aerosol performance over the six months irrespective of the storage RH. However, liposomal instability occurred at both RHs within the first month of storage with a significant drop in EE and an increase in liposome size (p-values < 0.05). Moreover, the IVR assay of CIP from lactose CNL showed a less controlled release and a substantial difference (f2 < 50) from its initial value after six months regardless of the storage RHs. In conclusion, dry powder inhalers of CNL were physiochemically stable in sucrose lyoprotectant when stored below 4 %RH at room temperature for six months.
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Affiliation(s)
- Isra Khatib
- Advanced Drug Delivery Group, Sydney Pharmacy School, Faculty of Medicine and Health, The University of Sydney, NSW 2006, Australia
| | - Wei-Ren Ke
- Advanced Drug Delivery Group, Sydney Pharmacy School, Faculty of Medicine and Health, The University of Sydney, NSW 2006, Australia
| | | | - Hak-Kim Chan
- Advanced Drug Delivery Group, Sydney Pharmacy School, Faculty of Medicine and Health, The University of Sydney, NSW 2006, Australia.
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Chang RYK, Chow MY, Khanal D, Chen D, Chan HK. Dry powder pharmaceutical biologics for inhalation therapy. Adv Drug Deliv Rev 2021; 172:64-79. [PMID: 33705876 DOI: 10.1016/j.addr.2021.02.017] [Citation(s) in RCA: 43] [Impact Index Per Article: 14.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2020] [Revised: 02/17/2021] [Accepted: 02/25/2021] [Indexed: 12/13/2022]
Abstract
Therapeutic biologics such as genes, peptides, proteins, virus and cells provide clinical benefits and are becoming increasingly important tools in respiratory medicine. Pulmonary delivery of therapeutic biologics enables the potential for safe and effective treatment option for respiratory diseases due to high bioavailability while minimizing absorption into the systemic circulation, reducing off-target toxicity to other organs. Development of inhalable powder formulation requires stabilization of complex biological materials, and each type of biologics may present unique challenges and require different formulation strategy combined with manufacture process to ensure biological and physical stabilities during production and over shelf-life. This review examines key formulation strategies for stabilizing proteins, nucleic acids, virus (bacteriophages) and bacterial cells in inhalable powders. It also covers characterization methods used to assess physicochemical properties and aerosol performance of the powders, biological activity and structural integrity of the biologics, and chemical analysis at the nanoscale. Furthermore, the review includes manufacture technologies which are based on lyophilization and spray-drying as they have been applied to manufacture Food and Drug Administration (FDA)-approved protein powders. In perspective, formulation and manufacture of inhalable powders for biologic are highly challenging but attainable. The key requirements are the stability of both the biologics and the powder, along with the powder dispersibility. The formulation to be developed depends on the manufacture process as it will subject the biologics to different stresses (temperature, mechanical and chemical) which could lead to degradation by different pathways. Stabilizing excipients coupled with the suitable choice of process can alleviate the stability issues of inhaled powders of biologics.
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Modeling of a spray drying method to produce ciprofloxacin nanocrystals inside the liposomes utilizing a response surface methodology: Box-Behnken experimental design. Int J Pharm 2021; 597:120277. [PMID: 33540024 DOI: 10.1016/j.ijpharm.2021.120277] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2020] [Revised: 12/29/2020] [Accepted: 01/11/2021] [Indexed: 01/03/2023]
Abstract
Spray drying was previously used to modify the physical form of the encapsulated ciprofloxacin drug to produce ciprofloxacin nanocrystals inside the liposomes (CNL). The purpose of the present study was to optimize CNL powder production by evaluating the response surface via design of experiments (DoE). Using the Box-Behnken (BB) design, the study independent variables were the protectant type (sucrose, trehalose or lactose), protectant amount, drying temperature, and spray gas flow. Individual spray drying experiments were performed at various set points for each variable followed by characterization of the produced powders. Liposomal particle size, drug encapsulation efficiency (EE%), liposomal surface zeta potential, and nanocrystal dimensions were the design dependant variables. By applying the least square regression method on the experimental data, mathematical models were developed using the mathematical software package MATLAB R2018b. Model reliability and the significance of the model's factors were estimated using analysis of variance (ANOVA). The generated CNL powders showed spherical to elliptical liposomal vesicles with particle sizes ranging from 98 to 159 nm. The EE (%) ranged from 30 to 95% w/w while the zeta potential varied between -3.5 and -10.5 mV. The encapsulated ciprofloxacin nanocrystals were elongated cylindrical structures with an aspect ratio of 4.0-7.8. Coefficients of determination (R2 > 0.9) revealed a good agreement between the predicted and experimental values for all responses except for the nanocrystal dimensions. Sucrose and lactose were superior to trehalose in protecting the liposomes during spray drying. The amount of sugar significantly affected the characteristics of the CNL powders (p-value < 0.05). In conclusion, the DoE approach using BB design has efficiently modelled the generation of CNL by spray drying. The optimum processing conditions which produced high drug encapsulation (90%) after formation of nanocrystals and a vesicle size of ~125 nm utilized 57% (w/w) sucrose, an 80 °C inlet temperature, and an atomization rate of 742 L/hr.
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