Broad Scale and Structure Fabrication of Healthcare Materials for Drug and Emerging Therapies via Electrohydrodynamic Techniques

Abstract

The engineering of advanced healthcare materials provides a platform to address challenges facing interdisciplinary scientists, clinicians, pharmacists, biomaterial scientists, and biomedical engineers. Niche, timely developments arising from the synthesis or extraction of more biocompatible materials, new biologically active components, clearer insights into disease mechanisms, and novel therapies provide several timely opportunities. These include enhanced therapies with greater patient compliance, improved disease targeting, better diagnosis, and bespoke medications for individuals. Electrohydrodynamic atomization (EHDA) comprises several processes making use of electric fields interplaying with several forces. Coupled to advanced materials and specifically configured apparatuses, effective and controlled fabrication of various structures on various scales possessing various dimensions is readily achieved. The processes have distinct advantages compared to established engineering methods (ambient environment engineering, low shear, scalability, compartmentalization, etc.). This detailed review focuses on key concepts and developments in EHDA engineering pertaining to underlying principles, enabling tools and engineered structures specifically for healthcare remits. From initial experiments involving the behaviour of non‐formulated liquids on charged amber to recent developments in complex 3D matrix printing, the EHDA route has progressed significantly in the last two decades, and is capable of providing timely platform opportunities to tackle several global healthcare challenges.

Effect of Spray-Drying and Electrospraying as Drying Techniques on Lysozyme Characterisation

“…EHDA also known as electrospray is a drying technique used in the production of dry powder with the help of charges. It was first observed and recorded by Williams Gilbert in 1600 [22]. It is a process where a liquid imposes through a nozzle (which is connected to a voltage supply) at a certain flow rate, subjecting to high potential electric field.…”

“…A stable Taylor cone usually forms at the tip of the needle generating nearly uniform particles with distinct morphology. The incorporated protein disperses equally with the solution (without and with the excipient) improving the amorphous nature and bioavailability (Mehta et al [22]). Flow rate is highly related to the particle size of the electrosprayed particles.…”

“…Atomisation of materials by electrospraying relies mainly on evaporation of the solvent to generate dry particles without affecting the characteristics of proteins such as biological activity. While denaturation by the effect of temperature can be avoided, some denaturation and degradation might be initiated by the shear stress in the nozzle tip through which the aqueous solvent is infused [22,37,50,51]. In this study, the biological activity of freshly dried lysozyme forms was conserved by using electrospraying method compared with spray-drying technique.…”

Quality by Design Micro-Engineering Optimisation of NSAID-Loaded Electrospun Fibrous Patches

“…It is rapidly gaining attention in the pharmaceutical industry due to producing fibres with advantageous properties such as high porosity, flexibility, strong mechanics, and high ratio of surface area to volume [1]. Many scientists have dedicated their research to this remit with respect to the uses of these fibres, and due to their many appealing characteristics, many applications have been established [2,3]. These applications include biomedical engineering [4], imaging [5], specialised drug delivery systems [6], wound dressings and tissue engineering [7], and nano-encapsulation of bioactive compounds [8].…”

Assessing the ex vivo permeation behaviour of functionalised contact lens coatings engineered using an electrohydrodynamic technique

“…Electrohydrodynamic atomisation (EHDA), more specifically electrospinning was utilised in this instance to engineer fibrous coatings for contact lens surfaces. The on-demand, cost effective process has already shown its potential in an array of applications [7] including wound management [8][9][10][11][12][13], drug delivery [14][15][16][17][18][19][20][21][22] bioengineering [23][24][25][26] and theranostics [27]. Here, electrospun fibrous coatings were engineered to assess the ex vivo release and permeation of TM through freshly excised cornea as an extension of previous work [18].…”