Electrohydrodynamic Atomisation Driven Design and Engineering of Opportunistic Particulate Systems For Applications in Drug Delivery, Therapeutics and Pharmaceutics

The file attached to this record is the author's final peer reviewed version. The Publisher's final version can be found by following the DOI link.Electrohydrodynamic atomisation (EHDA) technologies have evolved significantly over the past decade; branching into several established and emerging healthcare remits through timely advances in the engineering sciences and tailored conceptual process designs. More specifically for pharmaceutical and drug delivery spheres, electrospraying (ES) has presented itself as a high value technique enabling a plethora of different particulate structures. However, when coupled with novel formulations (e.g. co-flows) and innovative device aspects (e.g., materials and dimensions), core characteristics of particulates are manipulated and engineered specifically to deliver an application driven need, which is currently lacking, ranging from imaging and targeted delivery to controlled release and sensing. This demonstrates the holistic nature of these emerging technologies; which is often overlooked. Parametric driven control during particle engineering via the ES method yields opportunistic properties when compared to conventional methods, albeit at ambient conditions (e.g., temperature and pressure), making this extremely valuable for sensitive biologics and molecules of interest. Furthermore, several processing (e.g., flow rate, applied voltage and working distance) and solution (e.g., polymer concentration, electrical conductivity and surface tension) parameters impact ES modes and greatly influence the production of resulting particles. The formation of a steady cone-jet and subsequent atomisation during ES fabricates particles demonstrating monodispersity (or near monodispersed), narrow particle size distributions and smooth or textured morphologies; all of which are successfully incorporated in a one-step process. By following a controlled ES regime, tailored particles with various intricate structures (hollow microspheres, nanocups, Janus and cell-mimicking nanoparticles) can also be engineered through process head modifications central to the ES technique (single-needle spraying, coaxial, multi-needle and needleless approaches). Thus, intricate formulation design, set-up and combinatorial engineering of the EHDA process delivers particulate structures with a multitude of applications in tissue engineering, theranostics, bioresponsive systems as well as drug dosage forms for specific delivery to diseased or target tissues. This advanced technology has great potential to be implemented commercially, particularly on the industrial scale for several unmet pharmaceutical and medical challenges and needs. This review focuses on key seminal developments, ending with future perspectives addressing obstacles that need to be addressed for future advancement

The use of nanoparticles and electrospun fibers for intravaginal delivery to treat viral and bacterial infections and electrophysiological measurements of synthetic chloride channels.

Female reproductive viral and bacterial infections affect millions of women worldwide. Given the diversity and magnitude of these unmet reproductive health challenges, topical administration of antiretrovirals (ARVs) and antibiotics have emerged as promising approaches to maintain and restore reproductive health. However, currently available intravaginal dosage forms often suffer from low user adherence and the need for frequent, daily administration to achieve therapeutic effect. To address these challenges, the broad goal of this research was to focus on the development of new localized nanoparticle (NP) and electrospun fiber dosage forms to prolong the delivery and enhance the efficacy of active agents to treat viral and bacterial infections. The first goal of this work was to evaluate the synergistic interactions between a biologic, Q-Griffithsin (Q-GRFT), and three ARVs − tenofovir (TFV), raltegravir (RAL), and dapivirine (DAP) − in free and encapsulated forms, to identify unique protein-drug synergies to prevent human immunodeficiency virus type 1 (HIV-1) infection. Free Q-GRFT and free ARV co-administration resulted in strong synergistic interactions, relative to administration of each active agent alone. Similarly, Q-GRFT NP and ARV NP co-administration resulted in synergy across all formulations, with the most potent interactions between encapsulated Q-GRFT and DAP. This work suggests that Q-GRFT and ARV co-administration in free or encapsulated forms may improve efficacy and decrease the dose required to achieve prophylaxis. Moreover, the encapsulation of different active agents in NP-based platforms may provide modest levels of sustained-release with utility to a variety of agents and infection types. The second part of this dissertation focused on the use of molecular dynamics (MD) and molecular mechanics simulations to study the compatibility of the mentioned ARVs with PLGA NPs. Solubility parameters were calculated for water, polymer, and each drug individually, and were compared with those attained from a group-contribution method (GCM). In addition, plots of the radial distribution function (RDF) and calculated charges obtained from electrostatic potential (ESP) fitting were used to compare the interactions between each drug and the polymer. Results indicated stronger hydrogen bonding between RAL and PLGA compared to TFV and PLGA. These findings explain the experimental observation that PLGA NPs encapsulating RAL have significantly higher encapsulation efficiency relative to NPs encapsulating TFV. This result provides important insight into the role of drug–polymer interactions on the encapsulation efficacy of small molecule antiretrovirals in polymeric NPs. The third goal of this dissertation was to develop a new electrospun fiber dosage form to promote vaginal microbiota health, with the potential to prolong probiotic delivery for bacterial vaginosis (BV) treatment. First, we examined the initial safety and efficacy of fast-dissolving polyethylene oxide (PEO) fibers formulated alone or with an antibiotic in an established murine model of BV infection. We then fabricated PEO and polyvinyl alcohol (PVA) fibers containing Lactobacillus acidophilus (L. acidophilus) as a model probiotic. In addition, different parameters including electrospinning solution, the use of fresh or lyophilized bacteria, and extended storage conditions were evaluated for their impact on L. acidophilus viability and fiber morphology. Our results show that probiotics are highly and viably incorporated in PEO and PVA fibers, and exhibit prolonged stability for up to 3 months within -20 or 4°C storage conditions. In addition, this study suggests that blank and antibiotic-containing PEO fibers are safe in vivo, inert to the vaginal mucosa in the absence and presence of Gardnerella vaginalis (G. vaginalis) infection, and capable of delivering effective therapeutics. In addition, probiotics were highly and viably incorporated in PEO and PVA fibers, and exhibited prolonged stability for up to 3 months within -20 or 4°C storage conditions. Furthermore, PEO and PVA fibers inhibited the viability and cell adhesion of G. vaginalis, in both soluble and epithelial-based co-culture assays, suggesting their ability to exert health-promoting effects against pathogenic species involved in BV. Lastly, we sought to build upon the baseline hydrophilic rapid release fiber dosage form to develop a fiber-based sustained-release delivery platform to prolong probiotic release for up to 2 weeks. Two different fiber architectures – mesh and layered – were developed to incorporate two lactic acid-producing model organisms, Lactobacillus crispatus (L. crispatus) and Lactobacillus acidophilus (L. acidophilus). In this study, fiber mass loss and morphology were assessed to evaluate fiber degradation over 2 wk, followed by the assessment of probiotic release and proliferation, lactic acid release, and changes in pH. Lastly, the efficacy of these fibers was evaluated in an in vitro soluble co-culture assay against G. vaginalis infection. Both fiber architectures prolonged probiotic release for up to 14 d and produced therapeutically-relevant levels of lactic acid, which correlated with a significant reduction in pH. Moreover, probiotic-containing fibers showed similar inhibitory properties to free probiotics against G. vaginalis, indicating that probiotics maintain their activity after electrospinning and have the potential to fully inhibit G. vaginalis infection. This study demonstrated that electrospun fibers composed of both hydrophilic and hydrophobic polymers may offer a viable long-term alternative to daily administration to maintain vaginal health, treat BV, and prevent BV recurrence

Polymer nanoparticles and nanofibers: Drug delivery and environmental applications

Since \u201cnanotechnology\u201d was presented by Nobel laureate Richard P. Feynman during his well famous 1959 lecture \u201cThere\u2019s Plenty of Room at the Bottom\u201d, there have been made various revolutionary developments in the field of nanotechnology. However, nanotechnology has emerged in the last decade as an exciting new research field. Nanotechnology represents the design, production, and application of materials at atomic, molecular and macromolecular scales, in order to produce new nanosized structures where at least one dimension is of roughly 1 to 100 nm, i.e., less than 0.1 \u3bcm. However, materials below or next to 1 \u3bcm (1000 nm) can be also commonly referred as nanomaterials or, more correctly, ultrathin materials. According to this, specifically within fiber science related literature, fibers with diameters below 1 \u3bcm are broadly accepted as nanofibers. Nanotechnology and nanoscience studies have emerged rapidly during the past years in a broad range of product domains. Today, nanoscience represents one of the rapidly growing scientific disciplines due to its enormous potential and impact in many different technological and engineering applications, which includes the development of new materials with novel and advanced performances. Recently, the nano-scaled materials have attracted extensive research interests due to their high anisotropy and huge specific surface area. Furthermore, the continuously increasing interest in the nanostructure materials results from their numerous potential applications in various areas, particularly in biomedical sciences. Today, nanofibers and nanoparticles are at the forefront of nanotechnology because of their unique properties such as low density, extremely high surface area to volume ratio, flexibility in surface functionalities, superior mechanical performance (e.g. stiffness and tensile strength), and high pore volume and controllable pore size that cannot be found in other structures. In this context, our researches have been concentrated on the production and modification of polymeric nanofibers and nanoparticles as drug delivery and environment applications. To this purpose, selected materials for the nanofibers development (polyhedral oligomeric silsesquioxanes, modified poly(amido-amine) dendrimers, and modified hyperbranched polyglycerol) were combined with biopolymers, namely (poly(L-lactide) (PLLA) and poly(\u3b5-caprolactone) (PCL) which enable us to overcome typical shortcomings of the above polymer matrices. As well, poly(styrene-co-maleic anhydride) (PSMA) amphiphilic copolymer was used for production of nanoparticles

Protein-based nanostructures for food applications

Proteins are receiving significant attention for the production of structures for the encapsulation of active compounds, aimed at their use in food products. Proteins are one of the most used biomaterials in the food industry due to their nutritional value, non-toxicity, biodegradability, and ability to create new textures, in particular, their ability to form gel particles that can go from macro- to nanoscale. This review points out the different techniques to obtain protein-based nanostructures and their use to encapsulate and release bioactive compounds, while also presenting some examples of food grade proteins, the mechanism of formation of the nanostructures, and the behavior under different conditions, such as in the gastrointestinal tract.Ricardo Pereira acknowledges his Post-Doctoral grant (SFRH/BPD/81887/2011) to the Fundação para a Ciência e Tecnologia (FCT, Portugal). This study was supported by the Portuguese Foundation for Science and Technology (FCT) under the scope of the strategic funding of UID/BIO/04469/2019 unit and BioTecNorte operation (NORTE-01-0145-FEDER-000004) funded by the European Regional Development Fund under the scope of Norte2020-Programa Operacional Regional do Norte.info:eu-repo/semantics/publishedVersio

Electrospun fibers and nanoparticles for the prevention of sexually transmitted infections.

Human immunodeficiency virus-1 (HIV-1) and herpes simplex virus 2 (HSV-2) affect hundreds of millions of people worldwide, with women disproportionately impacted by these infections. Currently, only oral pre-exposure prophylaxis (PrEP) is approved specifically for the prevention of HIV-1, but is challenged with adverse side effects associated with long-term use. Topical delivery platforms, such as gels and films, deliver agents directly to the female reproductive tract, but are limited in providing transient-release. The technology of polymeric electrospun fibers may serve as alternative topical delivery platform to the female reproductive tract. In these studies, we fabricated electrospun fibers comprised of different polymers or polymer blends that possess different physical attributes and fiber architectures. The goal was to provide sustained-release of agents such as the antiretroviral tenofovir disoproxil fumarate (TDF) and the antiviral lectin, Griffithsin (GRFT). We hypothesized that these delivery platforms would prevent HIV-1 and HSV-2 infections, while retaining the safety and biocompatibility of free agent. To determine the amount of GRFT loading and release from fiber formulations, ELISA was conducted, whereas TDF quantification was performed using absorbance measurements. Next, the in vitro efficacy of composites was assessed in HIV-1 and HSV-2 infectivity assays. From these initial results, multilayered fiber composites, free NPs, and hydrophilic fibers were tested for safety and antiviral efficacy within a murine model. Animal studies were conducted using 5-week-old female BALB/c mice, histology and cytokine expression were evaluated from mouse reproductive tracts and vaginal lavages collected 24 and 72 hr following platform administration. In parallel experiments, mice were administered fibers, followed by a single challenge 4 or 24 hr later with HSV-2 (LD90). Viral progression was monitored for 14 days post viral challenge to evaluate potential infection. Statistical significance for all studies was determined using one-way ANOVA with Bonferroni post hoc test (p \u3c 0.05), while log-ranked post hoc tests were used for antiviral efficacy studies. Future studies will consider encapsulation of multiple antiviral compounds to provide synergetic protection against infection

Natural Polymers in Micro- and Nanoencapsulation for Therapeutic and Diagnostic Applications: Part I: Lipids and Fabrication Techniques

Encapsulation, specifically microencapsulation is an old technology with increasing applications in pharmaceutical, agrochemical, environmental, food, and cosmetic spaces. In the past two decades, the advancements in the field of nanotechnology opened the door for applying the encapsulation technology at the nanoscale level. Nanoencapsulation is highly utilized in designing effective drug delivery systems (DDSs) due to the fact that delivery of the encapsulated therapeutic/diagnostic agents to various sites in the human body depends on the size of the nanoparticles. Compared to microencapsulation, nanoencapsulation has superior performance which can improve bioavailability, increase drug solubility, delay or control drug release and enhance active/passive targeting of bioactive agents to the sites of action. Encapsulation, either micro- or nanoencapsulation is employed for the conventional pharmaceuticals, biopharmaceuticals, biologics, or bioactive drugs from natural sources as well as for diagnostics such as biomarkers. The outcome of any encapsulation process depends on the technique employed and the encapsulating material. This chapter discusses in details (1) various physical, mechanical, thermal, chemical, and physicochemical encapsulation techniques, (2) types and classifications of natural polymers (polysaccharides, proteins, and lipids) as safer, biocompatible and biodegradable encapsulating materials, and (3) the recent advances in using lipids for therapeutic and diagnostic applications. Polysaccharides and proteins are covered in the second part of this chapter

Nanofibres in Drug Delivery

In recent years there has been an explosion of interest in the production of nanoscale fibres for drug delivery and tissue engineering. Nanofibres in Drug Delivery aims to outline to new researchers in the field the utility of nanofibres in drug delivery, and to explain to them how to prepare fibres in the laboratory. The book begins with a brief discussion of the main concepts in pharmaceutical science. The authors then introduce the key techniques that can be used for fibre production and explain briefly the theory behind them. They discuss the experimental implementation of fibre production, starting with the simplest possible set-up and then moving on to consider more complex arrangements. As they do so, they offer advice from their own experience of fibre production, and use examples from current literature to show how each particular type of fibre can be applied to drug delivery. They also consider how fibre production could be moved beyond the research laboratory into industry, discussing regulatory and scale-up aspects

Design and Fabrication of Polymeric Coatings based on Sustainable Materials and Processes

Polymeric coatings are getting more and more popular, due to their enhanced technical properties. Conventional coatings can be more practical by means of surface modifications to change the surface characteristics such as wetting properties, adhesion, conductivity and etc. This thesis will aim to provide an understanding about some surface properties and tuning the surface composition to obtain a final applications of the polymeric coatings. For this, different polymer nanocomposites were used by focusing on the sustainability of the materials and the simple fabrication process to have the chance to make them in large scale applications. After a general introduction about polymeric coatings, wetting properties, liquid repellent and thermally conductive coatings some of the materials and the methods, which can be used to fabricate these coatings and some applications of them are discussed in chapter 1. Subsequently, this thesis have been categorized into 5 independent sections with detailed results and discussions about each project that were done during this PhD thesis, followed by a general summary and conclusion. Each of this chapters are about: Chapter 2. Interfacing superhydrophobic silica nanoparticle films with graphene and thermoplastic polyurethane for wear/abrasion resistance Chapter 3. Superhydrophobic Coatings from Beeswax-in-water Emulsions with Latent Heat Storage Capability Chapter 4. Biocompatible liquid-repellent coating with anti-bacterial adhesion property Chapter 5. Thermally condcutive polymer coating decorated with in-situ synthesized silver nanoparticles and graphene nanoplatelets Chapter 6. Prespective and future idea

Polymer-based nanosystems for the delivery of therapeutic peptides and proteins

Η χρήση θεραπευτικών πρωτεϊνών και πεπτιδίων τόσο στον φαρμακευτικό τομέα όσο και στον τομέα της νανοτεχνολογίας έχει αναδειχθεί ιδιαίτερα τα τελευταία χρόνια. Η αποτελεσματική και ισχυρή δράση των πρωτεϊνών/πεπτιδίων τα καθιστά ικανά φάρμακα για την εφαρμογής τους στη θεραπεία πολλών ασθενειών όπως ο σακχαρώδης διαβήτης, ο καρκίνος, οι καρδιαγγειακές, μεταβολικές, μολυσματικές και νευρολογικές παθήσεις. Ωστόσο, είναι ασταθή βιομόρια όταν εκτίθενται σε διαφορετικά βιολογικά περιβάλλοντα, έχουν σύντομο χρόνο ζωής και ευαίσθητη τριτοταγής δομή και το υψηλό μοριακό τους βάρος περιορίζει τη διείσδυσή τους μέσω της βιολογικής μεμβράνης. Ως εκ τούτου, έχουν αναπτυχθεί διάφορες στρατηγικές προκειμένου να ξεπεραστούν αυτοί οι περιορισμοί και τελικά να επιτευχθεί η αποτελεσματική απελευθέρωση μέσω διαφόρων οδών χορήγησης. Τα νανοσυστήματα που βασίζονται σε πολυμερή χρησιμοποιούνται ευρέως για την πρόκληση ανοσοαπόκρισης και για την μεταφορά θεραπευτικών πρωτεϊνών/πεπτιδίων, τα οποία χαρακτηρίζονται από τα επιθυμητά φαρμακοκινητικά χαρακτηριστικά, στο επιθυμητό σημείο αποδέσμευσής τους. Σε αυτή την μεταπτυχιακή εργασία διπλώματος ειδίκευσης, μελετώνται τα φυσικά και συνθετικά πολυμερικά νανοσωματίδια, καθώς και οι παράμετροι που επηρεάζουν τις ικανότητες χρήσεις τους ως φορείς και μεταφοράς φαρμάκων όπως το μέγεθος, το σχήμα, η δομή και η επιφάνεια. Επιπλέον, παρουσιάζονται διάφορες τεχνικές παραγωγής που διαδραματίζουν σημαντικό ρόλο κατά τον σχεδιασμό των νανοσωματιδίων. Εν συνεχεία, αυτή η διατριβή εστιάζει σε διάφορα πολυμερή νανοσυστήματα τα οποία χρησιμοποιούνται για τη μεταφορά θεραπευτικών πρωτεϊνών με και πεπτιδίων ενώ ταυτοχρόνως παρουσιάζονται παραδείγματα μελετών από τη βιβλιογραφία. Τέλος, επισημαίνονται οι πολλά υποσχόμενες πρόσφατες μελέτες και κλινικές δοκιμές.The utilization of therapeutic proteins and peptides both in the pharmaceutical field and in the field of nanotechnology has dramatically emerged over recent years. The effective and potent action of the proteins/peptides makes them the drugs of choice for the treatment of numerous diseases including diabetes mellitus, cancer, cardiovascular, metabolic, infectious, and neurological diseases. However, they are unstable biomolecules under storage conditions and in biological milieus, they have a short half-life and fragile structure, and their high molecular weight limits permeation through the biological membrane. Hence, several strategies have been developed in order for these limitations to be overcome and finally, effective delivery through various routes of administration has been accomplished. Polymer-based nanosystems are widely utilized for eliciting an immune response and for delivering proteins/peptides therapeutic drugs to the systemic circulation with the desirable pharmacokinetics features and stability at their specific targeting sites. In this dissertation, the natural and synthetic polymeric nanoparticles, as well as the parameters which influence their ability of delivery such as the size, shape, structure, and surface are discussed. Furthermore, several production techniques which play an important role during the design of the nanoparticles are presented. Moving on, this dissertation focuses on the several polymer-based nanosystems and strategies for the delivery of therapeutic proteins and peptides with the simultaneous demonstration of examples from the literature. Finally, there are highlighted the promising up-to-date reviews and clinical trials

Advanced engineering of Fibrous Non-steroidal anti-inflammatory drug (NSAID) films for buccal application using Electrohydrodynamic Atomisation

The development of therapeutic dosage (e.g. pharmaceutical) systems is an ongoing process which, in recent times has incorporated several emerging disciplines and themes at timely intervals. While the concepts surrounding dosages have developed and evolved, many polymeric excipients remain as the preferred choice of materials over existing counterparts, serving functions as matrix materials, coatings and providing other specific functional properties (e.g. adhesion, controlled release and mechanical properties). Therefore, polymer is employed as a matrix carrier of materials or as active release performance modulating agents for polymeric based dosages. There have been, however, developments in the deployment of synthetic polymeric materials (e.g. polycaprolactone, poly lactic co-glycolic acid) when compared to naturally occurring materials (e.g. lactose, gelatin). Additionally, numerous techniques have been advanced further to novel engineering polymeric structures which provide materials in micrometer to nanometer scale range. Some of these structures enabling technologies include spray drying, super critical processing, microfluidics and even wet chemical methods. Recently maturing processes which is operational at the ambient environment is electrohydrodynamic (EHDA) engineering methods (ES and ESy). They have emerged as robust technologies offering potential to fabricate a plethora of generic structures directly into a fibrous polymer matrix system (e.g. particles, fibres, bubbles and pre-determined patterns) on a broad scale range. This research focuses on key developments using EHDA technology for the pharmaceutical and biomaterial remits when selecting synthetic and/or naturally occurring polymers as pharmaceutical (and therapeutic) excipients. EHDA was employed to engineer NSAID drugs in fibre film form for buccal delivery. EHDA was selected to develop fibre film of Indomethacin, Diclofenac Sodium, Ketoprofen, and Piroxicam in cooperation of PVP, Ethocel, Methocel, HPMC, and Tween 80. Morphology of electrospun films were analyzed by SEM and further characterized using DSC, TGA, FTIR, Raman and XRD. DSC and XRD demonstrated NSAID drugs change from crystalline to amorphous state. FTIR and Raman data suggest NSAID, PVP and co-polymers (Methocel™ E5, Methocel™ E15 Ethocel™ E10, HMPC and Tween® 80) were integrated in stable fashion into filamentous structures via ES. The release behaviour from several matrixes that was observed suggesting a potential route to modify drug release based on polymeric excipients. Therefore, identifying co-polymers in matrix and their effect in vitro release was the main core of chapter 3. Based on the results (fast or slow release), the co-polymer was incorporated with several NSAID drugs. However, each NSAID drugs show different release behaviour with same co-polymer. In addition, the underlying EHDA process principles are discussed along with key parameters and variables (both materials and engineering). EHDA technologies are operational at ambient conditions and recent developments have also demonstrated their viability for large scale production. These are promising technologies which have potential in established (e.g. films, dressings and microparticles) and emerging scientific themes (e.g. nanomedicines and tissue engineering). Moreover, EHDA a one-step process facilitates us to optimise dosage forms as desirable in a single step for several age groups. The use of EHDA need to be more explored within the buccal research concern. It has shown great potential in this research concept; therefore, it is viable to pursue to wider area in this field