Modified and derived ethanol injection toward liposomes: development of the process

Rapid Production of Nanoscale Liposomes Using a 3D-Printed Reactor-In-A-Centrifuge: Formulation, Characterisation, and Super-Resolution Imaging

Nanoscale liposomes have been extensively researched and employed clinically for the delivery of biologically active compounds, including chemotherapy drugs and vaccines, offering improved pharmacokinetic behaviour and therapeutic outcomes. Traditional laboratory-scale production methods often suffer from limited control over liposome properties (e.g., size and lamellarity) and rely on laborious multistep procedures, which may limit pre-clinical research developments and innovation in this area. The widespread adoption of alternative, more controllable microfluidic-based methods is often hindered by complexities and costs associated with device manufacturing and operation, as well as the short device lifetime and the relatively low liposome production rates in some cases. In this study, we demonstrated the production of liposomes comprising therapeutically relevant lipid formulations, using a cost-effective 3D-printed reactor-in-a-centrifuge (RIAC) device. By adjusting formulation- and production-related parameters, including the concentration of polyethylene glycol (PEG), temperature, centrifugation time and speed, and lipid concentration, the mean size of the produced liposomes could be tuned in the range of 140 to 200 nm. By combining selected experimental parameters, the method was capable of producing liposomes with a therapeutically relevant mean size of ~174 nm with narrow size distribution (polydispersity index, PDI ~0.1) at a production rate of >8 mg/min. The flow-through method proposed in this study has potential to become an effective and versatile laboratory-scale approach to simplify the synthesis of therapeutic liposomal formulations.

Ethanol Injection Method for Liposome Preparation

Ethanol injection method is one of the preferred methods for liposome preparation due to its advantages including rapidity, safety, and reproducibility. This method involves the injection of phospholipid solution of ethanol into a stirred aqueous solution. Due to the diffusion of ethanol in aqueous solution, the dissolved phospholipids precipitate to form bilayer phospholipid fragments, which further fuse to form closed liposomal structures. After evaporation of ethanol, the liposomes can be finally obtained. In this chapter, we will describe the details of ethanol injection method for preparing liposomes and discuss issues that need to be considered during the fabrication process.

Coupling EGFR-Antagonistic Affibody Enhanced Therapeutic Effects of Cisplatin Liposomes in EGFR-expressing Tumor Models

Epidermal growth factor receptor (EGFR) is an efficient target for cancer therapy. In this study, a high-affinity EGFR-antagonistic affibody (Z_EGFR) molecule coupled with cisplatin-loaded PEGylated liposomes (LS-DDP) was applied to actively target EGFR⁺ A431 tumor cells in vitro and in vivo. The LS-DDP coupled with Z_EGFR (AS-DDP) had an average size of 140.01 ± 0.84 nm, low polydispersity, a zeta potential of -13.40 ± 0.8 mV, an acceptable encapsulation efficiency of 17.30 ± 1.35%, and released cisplatin in a slow-controlled manner. In vitro, AS-DDP demonstrated a higher amount of platinum intracellular uptake by A431 cells than LS-DDP. The IC50 value of AS-DDP (9.02 ± 1.55 μg/ml) was much lower than that of LS-DDP (16.44 ± 0.87 μg/ml), indicating that the anti-tumor effects of AS-DDP were remarkable due to the modification of Z_EGFR. In vivo, the concentration of AS-DDP in the tumor site increased more than 1.76-fold, while an increase in apoptotic cells at 48 h compared to the LS-DDP was also observed, illustrating that AS-DDP possessed excellent tumor-targeting efficiency. As a result, the targeted nano-liposomes achieved greater tumor suppression. Therefore, selective targeting of LS-DDP coupled with Z_EGFR enhanced the anti-tumor effects and appeared to be a promising strategy for the treatment of EGFR⁺ tumors.

Liposomes for oral delivery of protein and peptide-based therapeutics: challenges, formulation strategies, and advances

Throughout the past decade, there has been a rapid growth in the development of protein/peptide-based therapeutics. These therapeutics have found widespread applications in the treatment of cancer, infectious diseases, and other metabolic disorders owing to their several desirable attributes, such as reduced toxicity, diverse biological activities, high specificity, and potency. Most protein/peptide-based drugs are still administered parenterally, and there is an unprecedented demand in the pharmaceutical industry to develop oral delivery routes to increase patient acceptability and convenience. Recent advancements in nanomedicine discoveries have led to the development of several nano and micro-particle-based oral delivery platforms for protein/peptide-based therapeutics and among these, liposomes have emerged as a prominent candidate. Liposomes are spherical vesicles composed of one or more phospholipid bilayers enclosing a core aqueous phase. Their unique amphiphilic nature enables encapsulation of a diverse range of bioactives/drugs including both hydrophobic and hydrophilic compounds for delivery. Against this backdrop, this review provides an overview of the current approaches and challenges associated with the routes and methods of oral administration of protein/peptide-based therapeutics by using liposomes as a potential vehicle. First, the conventional and innovative liposome formation approaches have been discussed along with their applications. Next, the challenges associated with current approaches for oral delivery of protein and peptide-derived therapeutics have been thoroughly addressed. Lastly, we have critically reviewed the potential of liposomes utilization as vehicles for oral delivery of proteins emphasizing the current status and future directions in this area.

Preparation and In Vitro Characterization of Enoxaparin Nano-liposomes through Different Methods

Purpose: Enoxaparin has been widely used as a choice drug for treatment and prevention of different coagulation disorders. Orally administered enoxaparin encounters with gastrointestinal barrier because of its high water solubility, high molecular weight and significant negative charge. Since, the nano-liposomes has gained great interest for oral drug delivery, we decided to introduce the best protocol for preparing enoxaparin nano-liposomes through in vitro characterization.

Methods: Nano-liposomes were prepared by ethanol injection, thin film hydration, and double emulsion/solvent evaporation methods. Size distribution, zeta potential, loading efficiencies, and in vitro drug release of nano-liposomes were also studied.

Results: The mean vesicle size was obtained under 100 nm, and the zeta potential was highly negative through all preparation methods. Nano-liposomes prepared by double emulsion/ solvent evaporation (DE) technique could entrap more of this hydrophilic drug (43 ± 7.1 %), but through thin layer hydration (TL) and ethanol injection (EI) only 28.4± 3.2% and 17.3 ± 2.5% of drug could be loaded into synthesized carriers. Drug release from these carriers was also obtained 42.17±1.72%, 29.43±0.34% and 32.27±0.14%, in 24 hours for EI, TL, and DE methods, respectively.

Conclusion: Here, we can introduce double emulsion/solvent evaporation method as an acceptable method for enoxaparin loading, although some toxicity and in-vivo tests are also necessary to fully understand the potential of this formulation.

Increased Encapsulation Efficiency of Methotrexate in Liposomes for Rheumatoid Arthritis Therapy

Methotrexate (MTX) is a common drug used to treat rheumatoid arthritis. Due to the excessive side effects, encapsulation of MTX in liposomes is considered an effective delivery system, reducing drug toxicity, while maintaining its efficacy. The ethanol injection method is an interesting technique for liposome production, due to its simplicity, fast implementation, and reproducibility. However, this method occasionally requires the extrusion process, to obtain suitable size distribution, and achieve a low level of MTX encapsulation. Here, we develop a novel pre-concentration method, based on the principles of the ethanol injection, using an initial aqueous volume of 20% and 1:1 ratio of organic:aqueous phase (v/v). The liposomes obtained present small values of size and polydispersity index, without the extrusion process, and a higher MTX encapsulation (efficiency higher than 30%), suitable characteristics for in vivo application. The great potential of MTX to interact at the surface of the lipid bilayer was shown by nuclear magnetic resonance (NMR) studies, revealing mutual interactions between the drug and the main phospholipid via hydrogen bonding. In vivo experiments reveal that liposomes encapsulating MTX significantly increase the biological benefit in arthritic mice. This approach shows a significant advance in MTX therapeutic applications.

Targeted Dual Intervention-Oriented Drug-Encapsulated (DIODE) Nanoformulations for Improved Treatment of Pancreatic Cancer

Despite recent advancements, effective treatment for pancreatic ductal adenocarcinoma (PDAC) has remained elusive. The overall survival rate in PDAC patients has been dismally low due to resistance to standard therapies. In fact, the failure of monotherapies to provide long-term survival benefits in patients led to ascension of several combination therapies for PDAC treatment. However, these combination therapies provided modest survival improvements while increasing treatment-related adverse side effects. Hence, recent developments in drug delivery methods hold the potential for enhancing therapeutic benefits by offering cocktail drug loading and minimizing chemotherapy-associated side effects. Nanoformulations-aided deliveries of anticancer agents have been a success in recent years. Yet, improving the tumor-targeted delivery of drugs to PDAC remains a major hurdle. In the present paper, we developed several new tumor-targeted dual intervention-oriented drug-encapsulated (DIODE) liposomes. We successfully formulated liposomes loaded with gemcitabine (G), paclitaxel (P), erlotinib (E), XL-184 (c-Met inhibitor, X), and their combinations (GP, GE, and GX) and evaluated their in vitro and in vivo efficacies. Our novel DIODE liposomal formulations improved median survival in comparison with gemcitabine-loaded liposomes or vehicle. Our findings are suggestive of the importance of the targeted delivery for combination therapies in improving pancreatic cancer treatment.

A Promising Biocompatible Platform: Lipid-Based and Bio-Inspired Smart Drug Delivery Systems for Cancer Therapy

Designing new drug delivery systems (DDSs) for safer cancer therapy during pre-clinical and clinical applications still constitutes a considerable challenge, despite advances made in related fields. Lipid-based drug delivery systems (LBDDSs) have emerged as biocompatible candidates that overcome many biological obstacles. In particular, a combination of the merits of lipid carriers and functional polymers has maximized drug delivery efficiency. Functionalization of LBDDSs enables the accumulation of anti-cancer drugs at target destinations, which means they are more effective at controlled drug release in tumor microenvironments (TMEs). This review highlights the various types of ligands used to achieve tumor-specific delivery and discusses the strategies used to achieve the effective release of drugs in TMEs and not into healthy tissues. Moreover, innovative recent designs of LBDDSs are also described. These smart systems offer great potential for more advanced cancer therapies that address the challenges posed in this research area.

Skin care and rejuvenation by cosmeceutical facial mask

Skin health is an important aspect of aesthetics. Dermatologists and scientists try to develop novel methods and materials to fulfill this aim. Facial cosmetics keep skin moist and remove sebum from the skin to maintain proper skin health. The use of suitable cosmetics according to the facial skin type results in healthy skin. Facial masks are the most prevalent cosmetic products utilized for skin rejuvenation. Facial masks are divided into four groups: (a) sheet masks; (b) peel-off masks; (c) rinse-off masks; and (d) hydrogels. Each of these has some advantages for specific skin types based on the ingredients used. The following article presents the available information about the facial mask. Also, we have focused on the facial masks available in the market. Despite several developments in this field, extensive research is required for performing successful and precise clinical trials in the future. Further improvements would enable the researchers to develop new products in this field. In this review, we present the most recent breakthroughs in the field of skin care and rejuvenation by cosmeceutical facial mask. This information is valuable to get the picture of the latest trends and also helpful for clinicians and related manufacturing companies.

Self-Assembly Behavior of Amphiphilic Janus Dendrimers in Water: A Combined Experimental and Coarse-Grained Molecular Dynamics Simulation Approach

Amphiphilic Janus dendrimers (JDs) are repetitively branched molecules with hydrophilic and hydrophobic components that self-assemble in water to form a variety of morphologies, including vesicles analogous to liposomes with potential pharmaceutical and medical application. To date, the self-assembly of JDs has not been fully investigated thus it is important to gain insight into its mechanism and dependence on JDs’ molecular structure. In this study, the aggregation behavior in water of a second-generation bis-MPA JD was evaluated using experimental and computational methods. Dispersions of JDs in water were carried out using the thin-film hydration and ethanol injection methods. Resulting assemblies were characterized by dynamic light scattering, confocal microscopy, and atomic force microscopy. Furthermore, a coarse-grained molecular dynamics (CG-MD) simulation was performed to study the mechanism of JDs aggregation. The obtaining of assemblies in water with no interdigitated bilayers was confirmed by the experimental characterization and CG-MD simulation. Assemblies with dendrimersome characteristics were obtained using the ethanol injection method. The results of this study establish a relationship between the molecular structure of the JD and the properties of its aggregates in water. Thus, our findings could be relevant for the design of novel JDs with tailored assemblies suitable for drug delivery systems.

Nanoparticles and nanofibers for topical drug delivery

This review provides the first comprehensive overview of the use of both nanoparticles and nanofibers for topical drug delivery. Researchers have explored the use of nanotechnology, specifically nanoparticles and nanofibers, as drug delivery systems for topical and transdermal applications. This approach employs increased drug concentration in the carrier, in order to increase drug flux into and through the skin. Both nanoparticles and nanofibers can be used to deliver hydrophobic and hydrophilic drugs and are capable of controlled release for a prolonged period of time. The examples presented provide significant evidence that this area of research has - and will continue to have - a profound impact on both clinical outcomes and the development of new products.

Curvature sensing MARCKS-ED peptides bind to membranes in a stereo-independent manner

Membrane curvature and lipid composition plays a critical role in interchanging of matter and energy in cells. Peptide curvature sensors are known to activate signaling pathways and promote molecular transport across cell membranes. Recently, the 25-mer MARCKS-ED peptide, which is derived from the effector domain of the myristoylated alanine-rich C kinase substrate protein, has been reported to selectively recognize highly curved membrane surfaces. Our previous studies indicated that the naturally occurring L-MARCKS-ED peptide could simultaneously detect both phosphatidylserine and curvature. Here, we demonstrate that D-MARCKS-ED, composed by unnatural D-amino acids, has the same activities as its enantiomer, L-MARCKS-ED, as a curvature and lipid sensor. An atomistic molecular dynamics simulation suggests that D-MARCKS-ED may change from linear to a boat conformation upon binding to the membrane. Comparable enhancement of fluorescence intensity was observed between D- and L-MARCKS-ED peptides, indicating similar binding affinities. Meanwhile, circular dichroism spectra of D- and L-MARCKS-ED are almost symmetrical both in the presence and absence of liposomes. These results suggest similar behavior of artificial D- and natural L-MARCKS-ED peptides when binding to curved membranes. Our studies may contribute to further understanding of how MARCKS-ED senses membrane curvature as well as provide a new direction to develop novel membrane curvature probes.

Phospholipid bilayer-coated aluminum nanoparticles as an effective vaccine adjuvant-delivery system

The phospholipid bilayer-coated aluminum nanoparticles (PLANs), formed via chemisorption, were prepared by reverse ethanol injection-lyophilization (REIL) utilizing the phosphophilicity of aluminum. The anhydrous antigen-loaded PLANs obtained by REIL proved stable, satisfying using the controlled-temperature-chain instead of the integrated cold-chain for distribution, and could be rehydrated to reconstitute instantly an aqueous suspension of the antigen-PLANs, which were more readily taken up by antigen-presenting cells and, when given subcutaneously to mice, induced more robust antigen-specific humoral and cellular immunoresponses but less local inflammation than the antigen-alum. Thus, the PLANs are a useful vaccine adjuvant-delivery system with advantages over the widely used naked alum.

Etoposide-loaded immunoliposomes as active targeting agents for GD2-positive malignancies

Systemic chemotherapeutics remain the standard of care for most malignancies even though they frequently suffer from narrow therapeutic index, poor serum solubility, and off-target effects. In this study, we have encapsulated etoposide, a topoisomerase inhibitor effective against a wide range of cancers, in surface-modified liposomes decorated with anti-GD2 antibodies. We characterized the properties of the liposomes using a variety of methods including dynamic light scattering, electron microscopy, and Fourier transformed infrared spectroscopy. We examined whether these immunoliposomes were able to target cell lines expressing varying levels of surface GD2 and affect cellular proliferation. Anti-GD2 liposomes were generally targeted in a manner that correlated with GD2 expression and inhibited proliferation in cell lines to which they were efficiently targeted. The mechanism by which the immunoliposomes entered targeted cells appeared to be via clathrin-dependent uptake as demonstrated using flow cytometry and confocal microscopy. These studies suggest that anti-GD2-targeted, etoposide-loaded liposomes represent a potential strategy for more effective delivery of anti-cancer drugs that could be used for GD2 positive tumors.

Emerging research and clinical development trends of liposome and lipid nanoparticle drug delivery systems

Liposomes are spherical-enclosed membrane vesicles mainly constructed with lipids. Lipid nanoparticles are loaded with therapeutics and may not contain an enclosed bilayer. The majority of those clinically approved have diameters of 50-300 nm. The growing interest in nanomedicine has fueled lipid-drug and lipid-protein studies, which provide a foundation for developing lipid particles that improve drug potency and reduce off-target effects. Integrating advances in lipid membrane research has enabled therapeutic development. At present, about 600 clinical trials involve lipid particle drug delivery systems. Greater understanding of pharmacokinetics, biodistribution, and disposition of lipid-drug particles facilitated particle surface hydration technology (with polyethylene glycol) to reduce rapid clearance and provide sufficient blood circulation time for drug to reach target tissues and cells. Surface hydration enabled the liposome-encapsulated cancer drug doxorubicin (Doxil) to gain clinical approval in 1995. Fifteen lipidic therapeutics are now clinically approved. Although much research involves attaching lipid particles to ligands selective for occult cells and tissues, preparation procedures are often complex and pose scale-up challenges. With emerging knowledge in drug target and lipid-drug distribution in the body, a systems approach that integrates knowledge to design and scale lipid-drug particles may further advance translation of these systems to improve therapeutic safety and efficacy.