Economical Feasibility Evaluation of an Ethanol Injection Liposome Production Plant

Preparation, pharmacokinetics and anti-obesity effects on dogs of nuciferine liposomes

BACKGROUND

Nuciferine (NUC), a natural compound extracted from lotus leaves, has been proven to have anti-obesity effects. However, the development and application of NUC as an anti-obesity drug in dogs are hindered due to its poor water solubility and low bioavailability.

OBJECTIVE

To promote the development of NUC-related products for anti-obesity in dogs, this study prepared NUC into a liposome formulation and evaluated its characteristics, pharmacokinetics in dogs, and anti-obesity effects on high-fat diet dogs.

METHODS

NUC liposomes were prepared by the ethanol injection method, using NUC, egg lecithin, and β-sitosterol as raw materials. The characteristics and release rate in vitro of liposomes were evaluated by particle size analyser and dialysis method, respectively. The pharmacokinetics in dogs after oral administration of NUC-liposomes was carried out by the high-performance liquid chromatography (HPLC) method. Moreover, we investigated the anti-obesity effect of NUC-liposomes on obese dogs fed with a high-fat diet.

RESULTS

NUC-liposome was successfully prepared, with an EE of (79.31 ± 1.06)%, a particle size of (81.25 ± 3.14) nm, a zeta potential of (-18.75 ± 0.23) mV, and a PDI of 0.175 ± 0.031. The cumulative release rate in vitro of NUC from NUC-liposomes was slower than that of NUC. The T1/2 and relative bioavailability of NUC-liposomes in dogs increased, and CL reduced compared with NUC. In addition, the preventive effect of NUC-liposomes on obesity in high-fat diet dogs is stronger than that of NUC.

CONCLUSIONS

The liposome formulation of NUC was conducive to improve its relative bioavailability and anti-obesity effect in dogs.

Rational formulation and industrial manufacturing of lipid-based complex injectables: Landmarks and trends

Lipid-based complex injectables are renowned for their effectiveness in delivering drugs, with many approved products. While significant strides have been made in formulating nanosystems for small molecular weight drugs, a pivotal breakthrough emerged with the recognition of lipid nanoparticles as a promising platform for delivering nucleic acids. This finding has paved the way for tackling long-standing challenges in molecular and delivery aspects (e.g., mRNA stability, intracellular delivery) that have impeded the clinical translation of gene therapy, especially in the realm of immunotherapy. Nonetheless, developing and implementing new lipid-based delivery systems pose significant challenges, as industrial manufacturing of these formulations often involves complex, multi-batch processes, giving rise to issues related to scalability, stability, sterility, and regulatory compliance. To overcome these obstacles, embracing the principles of quality-by-design (QbD) is imperative. Furthermore, adopting cutting-edge manufacturing and process analytical tools (PAT) that facilitate the transition from batch to continuous production is essential. Herein, the key milestones and insights derived from the development of currently approved lipid- nanosystems will be explored. Additionally, a comprehensive and critical overview of the latest technologies and regulatory guidelines that underpin the creation of more efficient, scalable, and flexible manufacturing processes for complex lipid-based nanoformulations will be provided.

Effect of Chitosan Coating for Efficient Encapsulation and Improved Stability under Loading Preparation and Storage Conditions of Bacillus Lipopeptides

This study aims to evaluate the effect of chitosan coating on the formation and properties of Bacillus cyclic lipopeptide (CLP)-loaded liposomes. A nanoencapsulation strategy for a chitosan-coated liposomal system using lecithin phospholipids for the entrapment of antibiotic CLP prepared from Bacillus subtilis KB21 was developed. The produced chitosan-coated CLP liposome had mean size in the range of 118.47-121.67 nm. Transmission electron microscopy showed the spherical-shaped vesicles. Fourier transform infrared spectroscopy findings indicated the successful coating of the produced CLP-loaded liposomes by the used chitosan. Liposomes coated with 0.2% and 0.5% chitosan concentration decreased the surface tension by 7.3-12.1%, respectively, and increased the CLP content by 15.1-27.0%, respectively, compared to the uncoating liposomes. The coated concentration of chitosan influenced their CLP loading encapsulation efficiency and release kinetics. The physicochemical results of the dynamic light scattering, CLP capture efficiency and long-term storage capacity of nanocapsules increased with chitosan coating concentration. Furthermore, the chitosan-coated liposomes exhibited a significant enhancement in the stability of CLP loading liposomes. These results may suggest the potential application of chitosan-coated liposomes as a carrier of antibiotics in the development of the functional platform.

Liposomal-Based Formulations: A Path from Basic Research to Temozolomide Delivery Inside Glioblastoma Tissue

Glioblastoma (GBM) is a lethal brain cancer with a very difficult therapeutic approach and ultimately frustrating results. Currently, therapeutic success is mainly limited by the high degree of genetic and phenotypic heterogeneity, the blood brain barrier (BBB), as well as increased drug resistance. Temozolomide (TMZ), a monofunctional alkylating agent, is the first line chemotherapeutic drug for GBM treatment. Yet, the therapeutic efficacy of TMZ suffers from its inability to cross the BBB and very short half-life (~2 h), which requires high doses of this drug for a proper therapeutic effect. Encapsulation in a (nano)carrier is a promising strategy to effectively improve the therapeutic effect of TMZ against GBM. Although research on liposomes as carriers for therapeutic agents is still at an early stage, their integration in GBM treatment has a great potential to advance understanding and treating this disease. In this review, we provide a critical discussion on the preparation methods and physico-chemical properties of liposomes, with a particular emphasis on TMZ-liposomal formulations targeting GBM developed within the last decade. Furthermore, an overview on liposome-based formulations applied to translational oncology and clinical trials formulations in GBM treatment is provided. We emphasize that despite many years of intense research, more careful investigations are still needed to solve the main issues related to the manufacture of reproducible liposomal TMZ formulations for guaranteed translation to the market.

Lipid nanovesicles for biomedical applications: 'What is in a name'?

Vesicles, generally defined as self-assembled structures formed by single or multiple concentric bilayers that surround an aqueous core, have been widely used for biomedical applications. They can either occur naturally (e.g. exosomes) or be produced artificially and range from the micrometric scale to the nanoscale. One the most well-known vesicle is the liposome, largely employed as a drug delivery nanocarrier. Liposomes have been modified along the years to improve physicochemical and biological features, resulting in long-circulating, ligand-targeted and stimuli-responsive liposomes, among others. In this process, new nomenclatures were reported in an extensive literature. In many instances, the new names suggest the emergence of a new nanocarrier, which have caused confusion as to whether the vesicles are indeed new entities or could simply be considered modified liposomes. Herein, we discussed the extensive nomenclature of vesicles based on the suffix "some" that are employed for drug delivery and composed of various types and proportions of lipids and others amphiphilic compounds. New names have most often been selected based on changes of vesicle lipid composition, but the payload, structural complexity (e.g. multicompartment) and new/improved proprieties (e.g. elasticity) have also inspired new vesicle names. Based on this discussion, we suggested a rational classification for vesicles.

Design of liposomes as drug delivery system for therapeutic applications

Liposomes are spherical vesicles consisting of one or more concentric phospholipid bilayers enclosing an aqueous core. Being both nontoxic and biodegradable, liposomes represent a powerful delivery system for several drugs. They have improved the therapeutic efficacy of drugs through stabilizing compounds, overcoming obstacles to cellular and tissue uptake and increasing drug biodistribution to target sites in vivo, while minimizing systemic toxicity. This review offers an overview of liposomes, thought the exploration of their key fundamentals. Initially, the main design aspects to obtain a successful liposomal formulation were addressed, following the techniques for liposome production and drug loading. Before application, liposomes required an extensive characterization to assurance in vitro and in vivo performance. Thus, several properties to characterize liposomes were explored, such as size, polydispersity index, zeta potential, shape, lamellarity, phase behavior, encapsulation efficiency, and in vitro drug release. Topics related with liposomal functionalization and effective targeting strategies were also addressed, as well as stability and some limitations of liposomes. Finally, this review intends to explore the current market liposomes used as a drug delivery system in different therapeutic applications.

Mastering the Tools: Natural versus Artificial Vesicles in Nanomedicine

Naturally occurring extracellular vesicles and artificially made vesicles represent important tools in nanomedicine for the efficient delivery of biomolecules and drugs. Since its first appearance in the literature 50 years ago, the research on vesicles is progressing at a fast pace, with the main goal of developing carriers able to protect cargoes from degradation, as well as to deliver them in a time- and space-controlled fashion. While natural occurring vesicles have the advantage of being fully compatible with their host, artificial vesicles can be easily synthetized and functionalized according to the target to reach. Research is striving to merge the advantages of natural and artificial vesicles, in order to provide a new generation of highly performing vesicles, which would improve the therapeutic index of transported molecules. This progress report summarizes current manufacturing techniques used to produce both natural and artificial vesicles, exploring the promises and pitfalls of the different production processes. Finally, pros and cons of natural versus artificial vesicles are discussed and compared, with special regard toward the current applications of both kinds of vesicles in the healthcare field.

New findings on the incorporation of essential oil components into liposomes composed of lipoid S100 and cholesterol

The encapsulation of essential oil components into liposomes was demonstrated to improve their solubility and chemical stability. In this study, we investigated the effect of chemical structure, Henry's law constant (H_c), and aqueous solubility of essential oil components on their liposomal encapsulation. Estragole, eucalyptol, isoeugenol, pulegone, terpineol, and thymol were encapsulated in lipoid S100-liposomes using the ethanol injection method. The H_c values were determined. The incorporation in liposomes was more efficient (encapsulation efficiency > 90%) for the essential oil components exhibiting low aqueous solubility (estragole, isoeugenol, and pulegone). Moreover, efficient entrapment into vesicles (loading rate > 18%) was obtained for isoeugenol, terpineol, and thymol. This result suggests that the presence of a hydroxyl group in the structure and a low Hc value enhance the entrapment of essential oil components into liposomes. Furthermore, drug release rate from liposomes was controlled by the loading rate of essential oil components into liposomes, the size of particles, the location of essential oil components within the lipid bilayer, and the cholesterol incorporation rate of liposomes. Finally, considerable concentrations of isoeugenol, pulegone, terpineol, and thymol were retained in liposomes after 10 months with respect to the initial concentration.

Adapting liposomes for oral drug delivery

Liposomes mimic natural cell membranes and have long been investigated as drug carriers due to excellent entrapment capacity, biocompatibility and safety. Despite the success of parenteral liposomes, oral delivery of liposomes is impeded by various barriers such as instability in the gastrointestinal tract, difficulties in crossing biomembranes, and mass production problems. By modulating the compositions of the lipid bilayers and adding polymers or ligands, both the stability and permeability of liposomes can be greatly improved for oral drug delivery. This review provides an overview of the challenges and current approaches toward the oral delivery of liposomes.

One Step Encapsulation of Small Molecule Drugs in Liposomes via Electrospray-Remote Loading

Resiquimod is a Toll-like receptor (TLR) 7/8 agonist that has previously been used as a vaccine adjuvant, as a topical treatment of viral lesions and skin cancer, and as an antiviral treatment. We report on the combined application of remote loading and electrospray to produce liposomal resiquimod, with the broader goals of improving drug encapsulation efficiency and scalability of liposome production methods. Drug loading in liposomes increased from less than 1% to greater that 3% by mass when remote loading was used, whether the liposomes were generated by thin-film hydration or electrospray methods. Dynamic light scattering (DLS) determined mean vesicle diameters of 137 ± 11 nm and 103 ± 4 for the thin-film and electrospray methods, respectively. Transmission electron microscopy (TEM) images showed spherical vesicles with sizes consistent with the DLS measurements. In vitro drug release profiles found that most of the drug remained within the liposomes at both pH 5.5 and 7.4. The in vitro bioactivity of the liposomal drug was also demonstrated by the increase in nitrite production when RAW macrophages were exposed to the drug. Our findings indicate that the remotely loaded liposomes formed via the scalable electrospray method have characteristics comparable to those produced via conventional batch methods. The methods discussed here are not limited to the enhanced delivery of resiquimod. Rather, they should be readily adaptable to other compounds compatible with remote loading.

Investigations on feasibility of in situ development of amphotericin B liposomes for industrial applications

Amphotericin B (AmB) liposome formulations are very successful in the treatment of fungal infections and leishmaniasis. But higher cost limits its widespread use among people in developing countries. Therefore, we have developed a modified ethanol-injection method for the preparation of AmB liposomes. Two liposomal formulations were developed with dimyristoyl phosphatidylcholine [F-1a] and soya phosphatidylcholine [F-2a], along with egg phosphatidyl glycerol and cholesterol. AmB was dissolved in acidified dimethyl acetamide and mixed with ethanolic lipid solution and rapidly injected in 5% dextrose to prepare liposomes. Liposomes were characterized on the basis of size (~100 nm), zeta (-43.3 ± 2.8 mV) and percent entrapment efficiency (>95%). The in vitro release study showed an insignificant difference (P ≥ 0.05) for 24-hour release between marketed AmB liposomes (AmBisome) and F-1a and F-2a. Proliposome concentrate, used for the preparation of in situ liposomes, was physically stable for more than 3 months at experimental conditions. Similarly, AmB showed no sign of degradation in reconstituted liposomes stored at 2-8°C for more than 3 months. IC(50) value of Ambisome (0.18 µg/mL) was comparatively similar to F-1a (0.17 µg/mL) and F-2a (0.16 µg/mL) against intramacrophagic amastigotes. Under experimental conditions, a novel modified method for AmB liposomes is a great success and generates interest for development as a platform technology for many therapeutic drug products.

Development of a liposomal formulation of the natural flavonoid fisetin

The natural flavonoid fisetin (3,3',4',7-tetrahydroxyflavone) has been shown to possess antiangiogenic and anticancer properties. Because of the limited water solubility of fisetin, our aim was to design and optimize a liposomal formulation that could facilitate its in vivo administration, taking into account the availability and cost of the various components. Several methods were evaluated such as probe sonication, homogeneization, film hydration and lipid cake formation. A selection of lipid and lipid-PEG was also performed via their incorporation in different formulations based on the size of the liposomes, their polydispersity index (PDI) and the fisetin encapsulation yield. An optimal liposomal formulation was developed with P90G and DODA-GLY-PEG2000, possessing a diameter in the nanometer scale (175nm), a high homogeneity (PDI 0.12) and a high fisetin encapsulation (73%). Fisetin liposomes were stable over 59 days for their particle diameter and still retained 80% of their original fisetin content on day 32. Moreover, liposomal fisetin retained the cytotoxicity and typical morphological effect of free fisetin in different tumour and endothelial cell lines. In conclusion, based on its physico-chemical properties and retention of fisetin biological effects, the developed liposomal fisetin preparation is therefore suitable for in vivo administration.