Electrohydrodynamic Atomization Research Articles

Engineered shapes using electrohydrodynamic atomization for an improved drug delivery.

The shapes of micro- and nano-products have profound influences on their functional performances, which has not received sufficient attention during the past several decades. Electrohydrodynamic atomization (EHDA) techniques, mainly include electrospinning and electrospraying, are facile in manipulate their products' shapes. In this review, the shapes generated using EHDA for modifying drug release profiles are reviewed. These shapes include linear nanofibers, round micro-/nano-particles, and beads-on-a-string hybrids. They can be further divided into different kinds of sub-shapes, and can be explored for providing the desired pulsatile release, sustained release, biphasic release, delayed release, and pH-sensitive release. Additionally, the shapes resulted from the organizations of electrospun nanofibers are discussed for drug delivery, and the shapes and inner structures can be considered together for developing novel drug delivery systems. In future, the shapes and the related shape-performance relationships at nanoscale, besides the size, inner structure and the related structure-performance relationships, would further play their important roles in promoting the further developments of drug delivery field. This article is categorized under: Therapeutic Approaches and Drug Discovery > Emerging Technologies.

Evaluation of 3D-Printed Solid Microneedles Coated with Electrosprayed Polymeric Nanoparticles for Simultaneous Delivery of Rivastigmine and N-Acetyl Cysteine.

In the current study, coated microneedle arrays were fabricated by means of digital light processing (DLP) printing. Three different shapes were designed, printed, and coated with PLGA particles containing two different actives. Rivastigmine (RIV) and N-acetyl-cysteine (NAC) were coformulated via electrohydrodynamic atomization (EHDA), and they were incorporated into the PLGA particles. The two actives are administered as a combined therapy for Alzheimer's disease. The printed arrays were evaluated regarding their ability to penetrate skin and their mechanical properties. Optical microscopy and scanning electron microscopy (SEM) were employed to further characterize the microneedle structure. Confocal laser microscopy studies were conducted to construct 3D imaging of the coating and to simulate the diffusion of the particles through artificial skin samples. Permeation studies were performed to investigate the transport of the drugs across human skin ex vivo. Subsequently, a series of tape strippings were performed in an attempt to examine the deposition of the APIs on and within the skin. Light microscopy and histological studies revealed no drastic effects on the membrane integrity of the stratum corneum. Finally, the cytocompatibility of the microneedles and their precursors was evaluated by measuring cell viability (MTT assay and live/dead staining) and membrane damages followed by LDH release.

Three-Dimensional-Printed GelMA-KerMA Composite Patches as an Innovative Platform for Potential Tissue Engineering of Tympanic Membrane Perforations.

Tympanic membrane (TM) perforations, primarily induced by middle ear infections, the introduction of foreign objects into the ear, and acoustic trauma, lead to hearing abnormalities and ear infections. We describe the design and fabrication of a novel composite patch containing photocrosslinkable gelatin methacryloyl (GelMA) and keratin methacryloyl (KerMA) hydrogels. GelMA-KerMA patches containing conical microneedles in their design were developed using the digital light processing (DLP) 3D printing approach. Following this, the patches were biofunctionalized by applying a coaxial coating with PVA nanoparticles loaded with gentamicin (GEN) and fibroblast growth factor (FGF-2) with the Electrohydrodynamic Atomization (EHDA) method. The developed nanoparticle-coated 3D-printed patches were evaluated in terms of their chemical, morphological, mechanical, swelling, and degradation behavior. In addition, the GEN and FGF-2 release profiles, antimicrobial properties, and biocompatibility of the patches were examined in vitro. The morphological assessment verified the successful fabrication and nanoparticle coating of the 3D-printed GelMA-KerMA patches. The outcomes of antibacterial tests demonstrated that GEN@PVA/GelMA-KerMA patches exhibited substantial antibacterial efficacy against Staphylococcus aureus, Pseudomonas aeruginosa, and Escherichia coli. Furthermore, cell culture studies revealed that GelMA-KerMA patches were biocompatible with human adipose-derived mesenchymal stem cells (hADMSC) and supported cell attachment and proliferation without any cytotoxicity. These findings indicated that biofunctional 3D-printed GelMA-KerMA patches have the potential to be a promising therapeutic approach for addressing TM perforations.

Turning fishery waste into aquafeed additives: Enhancing shrimp enzymes immobilization in alginate-based particles using electrohydrodynamic atomization

Alternative protein ingredients are gradually replacing fish meal in aquafeeds. However, farmed animals often struggle to digest the provided feed, which leads to inefficient nutrient assimilation. This results in a high feed conversion ratio and in water quality deterioration. Fish waste-derived proteases show great potential as bioactive ingredients to enhance protein digestibility. To achieve this, a suitable carrier is essential to include exogenous proteases in the fish feed formulation. Therefore, this research aimed to immobilize a shrimp enzyme extract into different alginate-based microcapsules through electrodynamic atomization and compare their structural and functional properties. Morphology, physicochemical and thermal properties, and in vitro protein release were evaluated for the following microcapsules made from various materials: alginate (A), alginate-chitosan (AC), alginate-bentonite (AB), alginate-bentonite previously subjected to a sonication treatment (ABs), and a combination of all materials (ABsC or ABC). The average sizes ranged from 360 to 790 μm (wet) and 260–516 μm (freeze-dried), confirming the expected differences, with larger sizes for those including chitosan and bentonite. ABsC proved to be the most suitable system for immobilizing exogenous proteases, as these particles exhibited high encapsulation efficiency in both wet and freeze-dried versions and displayed controlled protein release under typical conditions of the proximal intestine. This was further confirmed through an in vivo trial. Two bioassays were conducted with tilapia (Oreochromis niloticus) (n = 42, 2.6 ± 0.58 g) to evaluate the distribution of ABsC-rodamine labeled particles in digestive organs and digestive enzyme activity. ABsC remained in the intestine for over 7 h, and a significant increase in total proteolytic activity was observed 60 min after feeding. These findings suggest that ABsC microcapsules could serve as effective carriers for exogenous proteases in feeds for aquaculture.

In-flight electro-neutralisation electrospray for pulmonary drug delivery

Pulmonary drug delivery does not only provide non-invasive therapy for local lung diseases but also remarkably enhances systemic absorption of therapeutics owing to the tremendous surface area of the lung and fast transport of active molecules across the respiratory epithelia. In comparison to traditional delivery systems, electrohydrodynamic atomisation (EHDA) is superior in terms of size and production rate control but the high surface charges of resulting particles prohibit its use in drug delivery. To overcome this challenge, we developed an in-flight electro-neutralisation electrospray (IFENE) method which enables the generation of mists of particles in respirable size range with little to no charge. Our approach uses low-frequency alternating current (AC) to produce charge-neutralised sprays with initial velocity due to oppositely charged droplets combination. Experiments and simulations with pure liquid as the working solution were conducted to reveal the underlying mechanism. The applied frequency is found to be the main factor that influences spray stability and formation. Poly (vinylidene fluoride) (PVDF) and PVDF with curcumin solution were electrosprayed via IFENE, producing sprays of organic particles with controlled sizes and neutralised charges. The capability of coupling particle generation in the respirable size range (below 5 μm) and charge reduction (under 400 femtoamperes), along with its simple setup makes IFENE a promising platform technology in inhalation drug delivery.

Electrofluid in-situ forming MoS2-TiO2 lubricant-hard alternate coatings sintered at different temperatures

The study in-situ forms MoS2-TiO2 lubricant-hard alternate coatings with varying TiO2 sintering temperatures (400 °C/500 °C/600 °C/700 °C) on TC4 titanium alloy surfaces using the electrohydrodynamic atomization (EHDA) technique, and assesses the impact of sintering temperatures on reciprocating sliding wear of coating. The surface and interface microstructures, the interfacial bonding performance, and surface tribological properties of alternate coatings were compared with single material coatings. Results showed that MoS2-TiO2 alternate coating with TiO2 hard phase sintered at 600 °Ϲ exhibited the most effective lubrication, with a friction coefficient of ∼0.07, which reduced 42 % compared to the pure MoS2 coating. Its reciprocation wear life was 21 % shorter and the coating wear rate decreased 43.3 %. Additionally, the study analyzed the mechanism of the influence of sintering temperature on the lubrication of the alternate coatings and confirmed that the alternate TiO2 and MoS2 can effectively enhance the tribological properties compared to single material coating.

Two-step mask in-situ forming (CFx)n-TiO2/ZrO2 alternate coatings with different width ratios by electrohydrodynamic atomization

This paper utilizes a two-step mask process to prepare the crosswise lubricant-hard alternating coatings of (CFx)n-TiO2/ZrO2 with different width ratios, based on the electro-fluid in-situ forming technique. The research explored the micro morphologies, mechanical performance, sliding friction against 304 balls and wear properties of the coatings. A comparison was made with the (CFx)n-TiO2/ZrO2 composite laminate coating. X-ray diffraction and X-ray photoelectron spectroscopy results indicated the presence of Ti-O-Zr chemical bonds within the sintered TiO2/ZrO2 composite coatings. Dry friction tests revealed that the sample with a lubricant-hard coating width ratio of 2:1 (AT-D), exhibited the highest interfacial bonding performance (∼53.2 N) and the longest wear life (∼10658 s). The sample featuring a lubricant-hard coating width ratio of 1:1 (AT-C), displayed the lowest friction coefficient (∼0.13) and the smallest coating wear rate of 2.04×10−7 mm3 N−1 mm−1. These disparities could be attributed to the varying continuity of the self-lubricating film and the actual contact area between the mating components induced by different lubricant-hard coating width ratios.

Three EHDA Processes from a Detachable Spinneret for Fabricating Drug Fast Dissolution Composites

AbstractIn this study, three kinds of electrohydrodynamic atomization (EHDA) processes (electrospraying, electrospinning, and coaxial electrospinning) are implemented to create hydroxypropyl methylcellulose (HPMC) based ultra‐thin products for providing the fast dissolution of a poorly water‐soluble drug ketoprofen (KET). An EHDA apparatus, characterized by a novel spinneret, is homemade for conducting the three processes. The three types of products are electrospun nanofibers E1, electrosprayed microparticles E2, and core‐shell nanofibers E3. SEM and TEM results indicate that they have the anticipated morphologies and inner structures. X‐ray diffraction and Fourier Transform Infrared results verify that KET is mainly amorphous in all the composites due to its fine compatibility with HPMC. In vitro dissolution tests demonstrate that the drug rapid release performances has an order of E3>E1>E2≫KET powders. The fast dissolution mechanisms are suggested and the advantages of the three products are compared. The super performance of E3 in furnishing the rapid release is attributed to a synergistic action of small size (of the shell thickness), high porosity, amorphous state of drug, and the solubility of HPMC. EHDA nanostructures can support the development of nano drug delivery systems (DDSs) through tailoring the spatial distribution of drug molecules within the nano products.

Thick-film printing of TaS2 soft films on the textured surface to enhance wear life

As an additive manufacturing technology, 3D printing has become the new trend of film preparation in the future. Electrohydrodynamic atomization (EHDA), a new additive manufacturing technique, can produce films with a wide range of thicknesses. Although the synergistic effect of soft films and textured surfaces can effectively improve the tribological properties of the substrate, there are still problems such as poor interface bonding and short film life. Research into new microtextured and soft film materials is an important part of expanding the use of ceramic cutting tools in metal cutting applications. Herein, biomimetic Nepenthe convex textures and TaS2 soft films were prepared on the surface of Al2O3/TiC ceramic using nanosecond laser and EHDA processes, respectively. The results reveal that TaS2 films printed on biomimetic textured substrates had a longer wear life and lower wear rate. The synergistic effect of TaS2 films and biomimetic textures exhibits the best effect in reducing wear and improving the wear life of the substrate, which are expected to become a promising way to improve the tribological properties of Al2O3/TiC ceramic.

A combined electrohydrodynamic atomization method for preparing nanofiber/microparticle hybrid medicines.

Bacterial prostatitis is a challenging condition to treat with traditional dosage forms. Physicians often prescribe a variety of dosage forms with different administration methods, which fail to provide an efficient and convenient mode of drug delivery. The aim of this work was to develop a new type of hybrid material incorporating both electrosprayed core-shell microparticles and electrospun nanofibers. A traditional Chinese medicine (Ningmitai, NMT) and a Western medicine (ciprofloxacin, CIP) were co-encapsulated within this material and were designed to be released in a separately controlled manner. Utilizing polyvinylpyrrolidone (PVP) as a hydrophilic filament-forming polymer and pH-sensitive Eudragit® S100 (ES100) as the particulate polymeric matrix, a combined electrohydrodynamic atomization (EHDA) method comprising coaxial electrospraying and blending electrospinning, was used to create the hybrids in a single-step and straightforward manner. A series of characterization methods were conducted to analyze both the working process and its final products. Scanning electron microscopy and transmission electron microscopy revealed that the EHDA hybrids comprised of both CIP-PVP nanofibers and NMT-ES100 core-shell microparticles. Multiple methods confirmed the rapid release of CIP and the sustained release of NMT. The antibacterial experiments indicated that the hybrids exhibited a more potent antibacterial effect against Escherichia coli dh5α and Bacillus subtilis Wb800 than either the separate nanofibers or microparticles. The amalgamation of fibrous nanomedicine and particulate micromedicine can expand the horizon of new types of medicines. The integration of electrospinning and coaxial electrospraying provides a straightforward approach to fabrication. By combining hydrophilic soluble polymers and pH-sensitive polymers in the hybrids, we can ensure the separate sequential controlled release of CIP and NMT for a potential synergistic and convenient therapy for bacterial prostatitis.

A Study of Temperature Effect on the Dripping Mode of Electrohydrodynamic Atomization with Viscous Liquids

Electrohydrodynamic atomization (EHDA) has advantages in producing fine uniform droplets with low energy consumption. In this work, the droplets generated by the EHDA under the dripping mode have been captured by a backlit high-speed imaging system under various liquid temperatures T (293–343 K) and electric Bond numbers BoE (0–0.75). The temperature-viscosity relationships of the working fluids (G20, G40, G50, and G66) were fitted by an Arrhenius-type model. The effects of BoE, We, and T on the dimensionless droplet limiting length l* and oscillation frequency f were investigated through extensive experiments. The experimental results show that the droplet limiting length elongated with the higher liquid viscosity. However, the oscillation frequency of the meniscus declines with the liquid viscosity. By the elevation of liquid temperatures, the droplet limiting length diminishes, but the oscillation frequency of the liquid meniscus accelerates. Coefficients to estimate the effects of the flow rate and the temperature on oscillation frequency are introduced into the classical theory of meniscus oscillation to develop a semi-empirical model. The proposed model could estimate oscillation frequency for the meniscus under various electric Bond numbers, Weber numbers, and temperatures. The prediction achieves good agreements with experimental results.

Molecular dynamics simulation on electrohydrodynamic atomization: Stable dripping mode by pre-load voltage

Abstract The electrohydrodynamic atomization (EHDA) process is a method of forming liquid droplets or jets in a solution under an electric field. Molecular dynamics simulations were used in this study to reveal the EHDA dripping mode at a microscopic level. In this study, we investigated whether a liquid contains ions under the influence of a 1 V·nm−1 electric field that affects the dipole direction of water molecules to explore the cause of the dripping mode. It was hypothesized that the presence of ions would disrupt the local electric field distribution, causing liquid rupture. Furthermore, we observed the jetting behavior under varying ion concentrations and identified jetting instability. To solve this problem, the pre-load voltage method was used to control the distribution of ions in the solution, thus effectively increasing the ion concentration at the nanotube opening. In this study, we also investigated the movement behavior of ions in solution under different pre-load voltages, leading to a stable dripping mode under different ion concentrations. This study offers microscale mechanism research perspectives for EHDA and can be used in future studies for parameter setting and optimization.

Mineralized Microgels via Electrohydrodynamic Atomization: Optimization and In Vitro Model for Dentin-Pulp Complex.

There is growing interest in the use of micro-sized hydrogels, including bioactive signals, as efficient platforms for tissue regeneration because they are able to mimic cell niche structure and selected functionalities. Herein, it is proposed to optimize bioactive composite microgels via electrohydrodynamic atomization (EHDA) to regenerate the dentin-pulp complex. The addition of disodium phosphate (Na2HPO4) salts as mineral precursors triggered an in situ reaction with divalent ions in solution, thus promoting the encapsulation of different amounts of apatite-like phases. Morphological analysis via image analysis of optical images confirmed a narrow distribution of perfectly rounded particles, with an average diameter ranging from 223 ± 18 μm to 502 ± 64 μm as a function of mineral content and process parameters used. FTIR, TEM, and EDAX analyses confirmed the formation of calcium phosphates with a characteristic Ca/P ratio close to 1.67 and a needle-like crystal shape. In vitro studies-using dental pulp stem cells (DPSCs) in crown sections of natural teeth slices-showed an increase in cell viability until 14 days, recording a decay of proliferation at 21 days, independent on the mineral amount, suggesting that differentiation is started, as confirmed by the increase of ALP activity at 14 days. In this view, mineralized microgels could be successfully used to support in vitro osteogenesis, working as an interesting model to study dental tissue regeneration.

Bioactive Self-Regulated Liquified Microcompartments to Bioengineer Bone-Like Microtissues.

Designing a microenvironment that drives autonomous stromal cell differentiation toward osteogenesis while recapitulating the complexity of bone tissue remains challenging. In the current study, bone-like microtissues are created using electrohydrodynamic atomization to form two distinct liquefied microcapsules (mCAPs): i) hydroxypyridinone (HOPO)-modified gelatin (GH mCAPs, 7.5% w/v), and ii) HOPO-modified gelatin and dopamine-modified gelatin (GH+GD mCAPs, 7.5%+1.5% w/v). The ability of HOPO to coordinate with iron ions at physiological pH allows the formation of a semipermeable micro-hydrogel shell. In turn, the dopamine affinity for calcium ions sets a bioactive milieu for bone-like microtissues. After 21 days post encapsulation, GH and GH+GD mCAPs potentiate autonomous osteogenic differentiation of mesenchymal stem cells accompanied by collagen type-I gene upregulation, increased alkaline phosphatase (ALP)expression, and formation of mineralized extracellular matrix. However, the GH+GD mCAPs show higher levels of osteogenic markers starting on day 14, translating into a more advanced and organized mineralized matrix. The GH+GD system also shows upregulation of the receptor activator of nuclear factor kappa-B ligand (RANK-L) gene, enabling the autonomous osteoclastic differentiation of monocytes. These catechol-based mCAPs offer a promising approach to designing multifunctional and autonomous bone-like microtissues to study in vitro bone-related processes at the cell-tissue interface, angiogenesis, and osteoclastogenesis.

An additive manufacturing approach based on electrohydrodynamic printing to fabricate P3HT:PCBM thin films

Additive manufacturing (AM) enables the production of high value and high performance components with applications from aerospace to biomedical fields. We report here on the fabrication of poly(3-hexylthiophene): phenyl-C61-butyric acid methyl ester (P3HT:PCBM) thin films through the electrohydrodynamic atomization (EHDA) process and its integration as absorber layer for organic solar cells. Prior to the film fabrication, the optimization of the process was carried out by developing the operating envelope for the P3HT:PCBM ink to determine the optimal flow rate and the appropriate applied voltage to achieve a stable-cone deposition mode. The EHDA printed thin-film’s topography, morphology and optical properties were systematically analyzed. The root-mean-square roughness was found to vary significantly with the annealing temperature and the flow rate and ranged from 1.938 to 3.345 nm. The estimated film mass and thickness were found between 3.235 and 23.471 mg and 597.5 nm to 1.60 µm, respectively. The films exhibited a broad visible absorption spectrum ranging from ~ 340 to ~ 600 nm, with a maximum peak λmax located at ~ 500 nm. As the annealing temperature and the flow rate were increased, discernible alterations in the PCBM clusters were consequently observed in the blends of the film and the size of the PCBM clusters has decreased by 3% while the distance between them was highly reduced by as much as 82%.

Synergistic Effects of Ultrasonic Rolling Textures and PTFE‐PPS/SiO2 Coatings on Dry Friction and Wear Properties of GCr15 Steel Surfaces

Ultrasonic surface rolling processing (USRP) is used to fabricate textures with different shapes and processing times on the surface of GCr15 substrates. The polytetrafluoroethylene‐polyphenylene sulfide/silicon dioxide (PTFE‐PPS/SiO2) lubricant coating is subsequently deposited on texture surfaces by electrohydrodynamic atomization. USRP texturing not only forms the texture shapes but also realizes the strengthening effects of increased hardness and residual stress. Synergistic effects of the PTFE‐PPS/SiO2 coating and different USRP textures on dry friction and wear properties are investigated. The results show that the synergistic effect of the linear texture with two processing times and the PTFE‐PPS/SiO2 coating achieves better dry friction and wear performance than the individual effect. The texture shape and the processing times both affect the synergistic effect. The increase in processing times has a positive effect on synergistic improvement. The linear texture plays a better synergistic effect compared with that of the wavy texture with the same processing times. The USRP textures affect the tribological properties of texture‐coating samples by mainly influencing the coating‐substrate adhesion. The texture with an appropriate shape and height can improve the adhesion with the coating, and thus synergistically improve the dry friction and wear properties of the substrate.

Multilayer Ti3C2Tx MXene/graphene oxide/carbon fiber fabric/thermoplastic polyurethane composite for improved mechanical and electromagnetic interference shielding performance

The development of flexible electronics has placed higher demands on electromagnetic interference (EMI) shielding materials, especially in terms of mechanical properties. Herein, a novel composite with excellent mechanical and EMI shielding properties was developed. The electrohydrodynamic atomization deposition approach was used to deposit Ti3C2Tx MXene and graphene oxide (GO) nanosheets on carbon fiber fabric (CFf) surface, then they were assembled layer by layer with thermoplastic polyurethane (TPU) and thermoformed at high temperature to obtain MG/f-CFf/TPU composite. When the MXene/GO content increases, the mechanical performance of the composite is improved, mainly owing to the formation of chemical bonds and the presence of mechanical interlocking and van der Waals forces. Specifically, the tensile strength and interlaminar shear strength of the composite reach 140.98 MPa and 54.67 MPa, increasing by 72.45 % and 52.92 %, respectively. Benefitting from the unique lamellar structure, the maximum EMI-SE of MG/f-CFf/TPU composite is 38.29 dB. Besides, the MG/f-CFf/TPU composite also displays outstanding EMI-SE stability after 3000 times folding cycles. The flexible MG/f-CFf/TPU composite may provide more guidelines for the design of next-generation flexible EMI shielding materials.

Integrating Chinese Herbs and Western Medicine for New Wound Dressings through Handheld Electrospinning.

In this nanotechnology era, nanostructures play a crucial role in the investigation of novel functional nanomaterials. Complex nanostructures and their corresponding fabrication techniques provide powerful tools for the development of high-performance functional materials. In this study, advanced micro-nanomanufacturing technologies and composite micro-nanostructures were applied to the development of a new type of pharmaceutical formulation, aiming to achieve rapid hemostasis, pain relief, and antimicrobial properties. Briefly, an approach combining a electrohydrodynamic atomization (EHDA) technique and reversed-phase solvent was employed to fabricate a novel beaded nanofiber structure (BNS), consisting of micrometer-sized particles distributed on a nanoscale fiber matrix. Firstly, Zein-loaded Yunnan Baiyao (YB) particles were prepared using the solution electrospraying process. Subsequently, these particles were suspended in a co-solvent solution containing ciprofloxacin (CIP) and hydrophilic polymer polyvinylpyrrolidone (PVP) and electrospun into hybrid structural microfibers using a handheld electrospinning device, forming the EHDA product E3. The fiber-beaded composite morphology of E3 was confirmed through scanning electron microscopy (SEM) images. Fourier-transform infrared (FTIR) spectroscopy and X-ray diffraction (XRD) analysis revealed the amorphous state of CIP in the BNS membrane due to the good compatibility between CIP and PVP. The rapid dissolution experiment revealed that E3 exhibits fast disintegration properties and promotes the dissolution of CIP. Moreover, in vitro drug release study demonstrated the complete release of CIP within 1 min. Antibacterial assays showed a significant reduction in the number of adhered bacteria on the BNS, indicating excellent antibacterial performance. Compared with the traditional YB powders consisting of Chinese herbs, the BNS showed a series of advantages for potential wound dressing. These advantages include an improved antibacterial effect, a sustained release of active ingredients from YB, and a convenient wound covering application, which were resulted from the integration of Chinese herbs and Western medicine. This study provides valuable insights for the development of novel multiscale functional micro-/nano-composite materials and pioneers the developments of new types of medicines from the combination of herbal medicines and Western medicines.

Fabrication and characterization of superhydrophilic graphene-based electrospun membranes for efficient oil-water separation

This research article investigates the fabrication of superhydrophilic graphene-based electrospun membranes for efficient oil-water separation. The study utilizes cellulose acetate (CA) as the base material for membrane fabrication, employing an electrospinning technique followed by the electrohydrodynamic atomization of graphene oxide (GO) to enhance their hydrophilicity. The surface morphology, water contact angle, and Fourier Transform Infrared (FTIR) spectra of the fabricated membranes were analyzed to assess their properties. The membrane characterization techniques revealed the successful integration of GO nanosheets on the surface of the highly porous interconnected nanofibrous matrix. The modified membranes exhibited superhydrophilicity and underwater oleophobicity. The water contact angle of the optimized GO-based electrospun CA membrane was reduced from 110° to zero within 3 s. The performance of the membranes was evaluated through oil-water separation experiments using different types of oils (such as toluene, n-decane, and hexane) in water. The results demonstrated that the graphene-based optimized membranes exhibited high separation efficiency (3820 LMH), with a water permeation flux as high as 65.5 % compared to CA membranes (2308 LMH). The efficiency of separation while using all three different oils with DI water was calculated to be >99.9 %. The study provides valuable insights into the use of graphene-based membranes for oil-water separation and highlights the potential of the electrohydrodynamic atomization technique for the surface modification of membranes. The developed membranes have great potential applications in various industries, including oil and gas, chemical, and wastewater treatment.

Nebulization of PEGylated recombinant human deoxyribonuclease I using vibrating membrane nebulizers: A technical feasibility study

Recombinant human deoxyribonuclease I (rhDNase, Pulmozyme®) is the most frequently used mucolytic agent for the symptomatic treatment of cystic fibrosis (CF) lung disease. Conjugation of rhDNase to polyethylene glycol (PEG) has been shown to greatly prolong its residence time in the lungs and improve its therapeutic efficacy in mice. To present an added value over current rhDNase treatment, PEGylated rhDNase needs to be efficiently and less frequently administrated by aerosolization and possibly at higher concentrations than existing rhDNase. In this study, the effects of PEGylation on the thermodynamic stability of rhDNase was investigated using linear 20 kDa, linear 30 kDa and 2-armed 40 kDa PEGs. The suitability of PEG30-rhDNase to electrohydrodynamic atomization (electrospraying) as well as the feasibility of using two vibrating mesh nebulizers, the optimized eFlow® Technology nebulizer (eFlow) and Innospire Go, at varying protein concentrations were investigated. PEGylation was shown to destabilize rhDNase upon chemical-induced denaturation and ethanol exposure. Yet, PEG30-rhDNase was stable enough to withstand aerosolization stresses using the eFlow and Innospire Go nebulizers even at higher concentrations (5 mg of protein per ml) than conventional rhDNase formulation (1 mg/ml). High aerosol output (up to 1.5 ml per min) and excellent aerosol characteristics (up to 83% fine particle fraction) were achieved while preserving protein integrity and enzymatic activity. This work demonstrates the technical feasibility of PEG-rhDNase nebulization with advanced vibrating membrane nebulizers, encouraging further pharmaceutical and clinical developments of a long-acting PEGylated alternative to rhDNase for treating patients with CF.