A Facile and Novel Approach to Manufacture Paclitaxel-Loaded Proliposome Tablet Formulations of Micro or Nano Vesicles for Nebulization

Exploring the influence of microstructure and phospholipid type of liposomes on their interaction with lung

Liposome is a promising carrier for pulmonary drug delivery and the nano-sized liposomes have been widely investigated in the treatment of lung diseases. However, there still lack the knowledge of micron-sized liposomes for lung delivery, which have more advantages in terms of drug loading and sustained drug release capacity. The micron-sized liposomes can be classified into multilamellar liposome (MLL) and multivesicular liposome (MVL) according to their microstructure, thus, this study focused on exploring how the micron-sized liposomes with different microstructure and phospholipid composition influence their interaction with the lung. The MLL and MVL were prepared from different types of phospholipids (including soya phosphatidylcholine (SPC), egg yolk phosphatidylcholine (EPC), and dipalmitoyl phosphatidylcholine (DPPC)) with geometric diameter around 5 μm, and their in vitro pulmonary cell uptake, in vivo lung retention and organ distribution were investigated. The results showed that the microstructure of liposomes didn't affect pulmonary cellular uptake, in vivo lung retention and organ distribution. MLL and MVL prepared with the same phospholipid had similar cellular uptake in both NR8383 cells and A549 cells, and both of them possessed prolonged lung retention and limited distribution in other organs during 72 h. Notably, the phospholipid type presented remarkable influence on liposomes' interaction with the lung. SPC-based liposomes exhibited higher cellular uptake than the DPPC-based ones in both NR8383 cells and A549 cells, also possessed a better lung retention behavior. In conclusion, this study might provide theoretical knowledge for designing micron-sized liposomes intended for lung delivery.

Nanostructured lipid carriers (NLCs): A promising candidate for lung cancer targeting

Lung cancer stands as the foremost health issue and the principal reason for mortality worldwide. It is projected that India will see over 1.73 million new cases and more than 880,000 deaths related to cancer, with lung cancer being a significant contributor. The efficiency of existing chemotherapy procedures is not optimal because of less soluble nature and short half-life of anticancer substances. More precipitated toxicity and non-existence of targeting propensity can lead to severe side effects, non-compliance, and inconvenience for patients. Nonetheless, the domain of nanomedicine has undergone a revolution in the past few years with the advent of novel drug delivery mechanisms that tackle the drawbacks of conventional approaches. Diverse nanoparticle-based drug delivery methods, including liposomes, nanoparticles, nanostructured lipid carrier and solid lipid nanoparticle that encapsulated chemotherapy drugs, are currently employed for efficient lung cancer therapy. NLCs, recognized as the second-generation lipid nanocarriers, are a focused drug delivery mechanism that has garnered significant interest owing to their multitude of advantages such as increased stability, minimal toxicity, prolonged shelf life, superior encapsulation capability, and biocompatible nature. This review focuses on the NLCs carrier system, discussing its preparation methods, types, characterization, applications, and future prospects in lung cancer treatment.

Transferosomes as a transdermal drug delivery system: Dermal kinetics and recent developments

The development of innovative approaches to deliver medications has been growing now for the last few decades and generates a growing interest in the dermatopharmaceutical field. Transdermal drug delivery in particular, remains an attractive alternative route for many therapeutics. However, due to the limitations posed by the barrier properties of the stratum corneum, the delivery of many pharmaceutical dosage forms remains a challenge. Most successful therapies using the transdermal route have been ones containing smaller lipophilic molecules with molecular weights of a few hundred Daltons. To overcome these limitations of size and lipophilicity of the drugs, transferosomes have emerged as a successful tool for transdermal delivery of a variety of therapeutics including hydrophilic actives, larger molecules, peptides, proteins, and nucleic acids. Transferosomes exhibit a flexible structure and higher surface hydrophilicity which both play a critical role in the transport of drugs and other solutes using hydration gradients as a driving force to deliver the molecules into and across the skin. This results in enhanced overall permeation as well as controlled release of the drug in the skin layers. Additionally, the physical-chemical properties of the transferosomes provide increased stability by preventing degradation of the actives by oxidation, light, and temperature. Here, we present the history of transferosomes from solid lipid nanoparticles and liposomes, their physical-chemical properties, dermal kinetics, and their recent advances as marketed dosage forms. This article is categorized under: Biology-Inspired Nanomaterials > Lipid-Based Structures Therapeutic Approaches and Drug Discovery > Emerging Technologies.

Recent Advances in the Microencapsulation of Essential Oils, Lipids, and Compound Lipids through Spray Drying: A Review

In recent decades, the microcapsules of lipids, compound lipids, and essential oils, have found numerous potential practical applications in food, textiles, agricultural products, as well as pharmaceuticals. This article discusses the encapsulation of fat-soluble vitamins, essential oils, polyunsaturated fatty acids, and structured lipids. Consequently, the compiled information establishes the criteria to better select encapsulating agents as well as combinations of encapsulating agents best suited to the types of active ingredient to be encapsulated. This review shows a trend towards applications in food and pharmacology as well as the increase in research related to microencapsulation by the spray drying of vitamins A and E, as well as fish oil, thanks to its contribution of omega 3 and omega 6. There is also an increase in articles in which spray drying is combined with other encapsulation techniques, or modifications to the conventional spray drying system.

Impact of dispersion media and carrier type on spray-dried proliposome powder formulations loaded with beclomethasone dipropionate for their pulmonary drug delivery via a next generation impactor

Drug delivery via aerosolization for localized and systemic effect is a non-invasive approach to achieving pulmonary targeting. The aim of this study was to prepare spray-dried proliposome (SDP) powder formulations to produce carrier particles for superior aerosolization performance, assessed via a next generation impactor (NGI) in combination with a dry powder inhaler. SDP powder formulations (F1-F10) were prepared using a spray dryer, employing five different types of lactose carriers (Lactose monohydrate (LMH), lactose microfine (LMF), lactose 003, lactose 220 and lactose 300) and two different dispersion media. The first dispersion medium was comprised of water and ethanol (50:50% v/v ratio), and the second dispersion medium comprised wholly of ethanol (100%). In the first dispersion medium, the lipid phase (consisting of Soya phosphatidylcholine (SPC as phospholipid) and Beclomethasone dipropionate (BDP; model drug) were dissolved in ethanol and the lactose carrier in water, followed by spray drying. Whereas in second dispersion medium, the lipid phase and lactose carrier were dispersed in ethanol only, post spray drying. SDP powder formulations (F1-F5) possessed significantly smaller particles (2.89 ± 1.24-4.48 ± 1.20 μm), when compared to SDP F6-F10 formulations (10.63 ± 3.71-19.27 ± 4.98 μm), irrespective of lactose carrier type via SEM (scanning electron microscopy). Crystallinity of the F6-F10 and amorphicity of F1-F15 formulations were confirmed by XRD (X-ray diffraction). Differences in size and crystallinity were further reflected in production yield, where significantly higher production yield was obtained for F1-F5 (74.87 ± 4.28-87.32 ± 2.42%) then F6-F10 formulations (40.08 ± 5.714-54.98 ± 5.82%), irrespective of carrier type. Negligible differences were noted in terms of entrapment efficiency, when comparing F1-F5 SDP formulations (94.67 ± 8.41-96.35 ± 7.93) to F6-F10 formulations (78.16 ± 9.35-82.95 ± 9.62). Moreover, formulations F1-F5 demonstrated significantly higher fine particle fraction (FPF), fine particle dose (FPD) and respirable fraction (RF) (on average of 30.35%, 890.12 μg and 85.90%) when compared to counterpart SDP powder formulations (F6-F10). This study has demonstrated that when a combination of water and ethanol was employed as dispersion medium (formulations F1-F5), superior formulation properties for pulmonary drug delivery were observed, irrespective of carrier type employed.

A drift on liposomes to proliposomes: recent advances and promising approaches

Liposomes are nano-structured vesicles, made up of phospholipids that provide active ingredients at the site of action at a predetermined rate and add the advantage of the sustained-release formulation. Liposomes have stability issues that tend to agglomerate and fuse upon storage, which reflects their drawback. Hence to overcome the aggregation, fusion, hydrolysis, and/or oxidation problems associated with liposomes a new technology named Proliposomes has been introduced. Proliposomes are defined as carbohydrate carriers coated with phospholipids, which upon addition of water generate liposomes. The objective of the review is to cover the concept of proliposomes for pulmonary or alveolar delivery of drugs and compare it with that of liposomes; highlight the methods used for preparations along with the characterization parameters. This is the first systematic review that covers the categorization of liposomes, characteristic methods, and recent examples of drugs from 2015 to 2021, supplied in form of proliposomes to the macrophages as well as others and offers an advantage over the free drug by offering a prolonged drug release and sufficient bioavailability in addition to overcome the stability issues related to liposomes. Since this is a very new technology and many scientists are continuously working in this field to make the drug available for clinical trials and ultimately in the market for the targeted delivery of drugs with better storage life.HIGHLIGHTSProliposomes as an alternative to overwhelm the stability and storage-related issues of liposomes.Anhydrous carbohydrate carriers are utilized for proliposomal preparation.Inhaled delivery of drugs as solid lipid nanoparticles offers a significant impact on pulmonary tract infections, particularly in cystic fibrosis.Size of liposomes attained after proliposome hydrolysis is critical for drug delivery via respiration.

New repurposed rolapitant in nanovesicular systems for lung cancer treatment: Development, in-vitro assessment and in-vivo biodistribution study

Lung cancer is characterized by poor prognosis, and is considered a serious disease that causes a significant mortality. The available conventional chemotherapeutic agents suffer from several limitations; hence, new drug molecules are constantly being sought. In the current study, lipid nanovesicles (LNVs) were selected as a colloidal vehicle for encapsulation of the FDA-approved drug; rolapitant (RP), which is used particularly for the treatment of nausea and vomiting, but is repurposed for the treatment of lung cancer in the current work. RP was loaded into various LNVs (liposomes, ethosomes and transethosomes) using the thin film hydration method, and the LNVs were evaluated for particle size, zeta potential, entrapment efficiency (EE%), storage stability and surface morphology. Besides, the in-vitro drug release, in-vitro cytotoxicity on A549 lung cancer cells, nebulization performance using next generation impactor (NGI), and the in-vivo biodistribution behaviour were evaluated. The selected ethosomal and transethosomal vesicles displayed a particle size less than 400 nm, a positive charge, and EE% exceeding 90% for RP, with a sustained release pattern over 15 days. The in-vivo biodistribution results proved the high lung deposition potential of RP-LNVs with a considerable safety. Besides, the developed RP-LNVs were able to reach the metastatic organs of lung cancer, hence they were proven promising as a possible treatment modality for lung cancer.

Nanotherapeutics in the treatment of acute respiratory distress syndrome

Acute respiratory distress syndrome (ARDS) is a form of oxygenation failure primarily characterized by rapid inflammation resulting from a direct pulmonary or indirect systemic insult. ARDS has been a major cause of death in the recent COVID-19 outbreak wherein asymptomatic respiratory tract infection progresses to ARDS from pneumonia have emphasized the need for a reliable therapy for the disease. The disease has a high mortality rate of approximately 30-50%. Despite the high mortality rate, a dearth of effective pharmacotherapy exists that demands extensive research in this area. The complex ARDS pathophysiology which remains to be understood completely and the multifactorial etiology of the disease has led to the poor diagnosis, impeded drug-delivery to the deeper pulmonary tissues, and delayed treatment of the ARDS patients. Besides, critically ill patients are unable to tolerate the off-target side effects. The vast domain of nanobiotechnology presents several drug delivery systems offering numerous benefits such as targeted delivery, prolonged drug release, and uniform drug-distribution. The present review presents a brief insight into the ARDS pathophysiology and summarizes conventional pharmacotherapies available to date. Furthermore, the review provides an updated report of major developments in the nanomedicinal approaches for the treatment of ARDS. We also discuss different nano-formulations studied extensively in the ARDS preclinical models along with underlining the advantages as well as challenges that need to be addressed in the future.

The Effects of Solid and Liquid Lipids on the Physicochemical Properties of Nanostructured Lipid Carriers

The aim of this work was to identify from a review of current literature the effects of lipids used in the development of Nanostructured Lipid Carriers (NLCs) on the physicochemical properties of the resulting formulation. The size of the solid lipid, affected by the molecular weight and the complexity of the structure, tends to affect the particle size of the final formulation proportionally; the higher the molecular weight and the more complex the molecular structure, the bigger the particle size of the NLCs. However, there is no straight correlation between the size and the structure of the liquid lipid and the particle size. Moreover, there seems to be a correlation of the solid to liquid lipid ratio which affects the particle size; there has been a trend of increasing particle size when more solid lipid was used. Regarding the entrapment efficiency, it is highly affected by the drug and its interaction with the lipids, as its solubility in the lipids needs to be high so the drug can stay entrapped within the lipid core. There was no direct correlation between the type of lipid used or the ratio and the zeta potential, which affects the stability of the NLCs.

Cyclodextrin-based metal-organic frameworks for pulmonary delivery of curcumin with improved solubility and fine aerodynamic performance

Pulmonary drug delivery has attracted considerable attention in recent years. However, it is still a major challenge to deliver poorly water-soluble drugs to lungs with good solubility and fine aerodynamic performance. In this study, curcumin was loaded into cyclodextrin-based metal-organic frameworks (CD-MOFs) for pulmonary delivery. Compared with micronized curcumin prepared by jet milling, curcumin-loaded CD-MOFs (Cur-CD-MOFs) exhibited excellent aerodynamic performance, which was attributed to the unique porous structure and lower density of CD-MOFs. The dissolution test showed that the drug release rate of Cur-CD-MOFs was much faster than that of micronized curcumin. The all-atom molecular dynamic simulation showed that curcumin molecules were loaded into the hydrophobic cavities of CD-MOFs or entered into the large hydrophilic cavities to form nanoclusters. The elevated wettability of Cur-CD-MOFs and the unique spatial distribution feature of curcumin in porous interior of CD-MOFs might be favorable for the improved dissolution rate. The DPPH radical scavenging test showed that Cur-CD-MOFs had prominent antioxidant activities. Therefore, CD-MOFs were expected to be promising carriers for pulmonary delivery of poorly water-soluble drugs.

Proliposome powder or tablets for generating inhalable liposomes using a medical nebulizer

Purpose

The aim of this study was to develop and compare proliposome powder and proliposome tablet formulations for drug delivery from a Pari-LC Sprint nebulizer.

Methods

Proliposome powders were prepared by the slurry method and sorbitol or mannitol carbohydrate carrier were used in a 1:10 and 1:15 w/w lipid phase to carrier ratio. Beclometasone dipropionate (BDP; 2 mol%) was incorporated in the lipid phase. Proliposome powders were compressed into tablets, and liposomes were generated from proliposome powders or tablets within the nebulizer reservoir for subsequent aerosolization.

Results

Comparatively, shorter sputtering times were reported for the tablet formulations (≈ < 2.7±0.45 min), indicating uniform aerosolization. Post-nebulization, liposomes size was larger in the nebulizer reservoir in the range of 7.79±0.48 µm–9.73±1.53 µm for both powder and tablet formulations as compared to freshly prepared liposomes (5.38±0.73 µm–5.85±0.86 µm), suggesting liposome aggregation/fusion in the nebulizer’s reservoir. All formulations exhibited more than 80% mass output regardless of formulation type, but greater BDP proportions (circa 50%) were delivered to the Two-stage Impinger when tablet formulations were used. Moreover, the nebulized droplet median size and size distribution were lower for all tablet formulations in comparison to the powder formulations. Proliposome tablet and powdered formulations demonstrated the ability to generate vesicles that sustained the release of BDP.

Conclusion

Overall, this study showed that proliposome tablets could be disintegrated within a Pari-LC Sprint nebulizer to generate inhalable aerosol, with high drug output and hence can be manufactured on large scale to overcome the storage problems associated with powder formulations.