Fluidity enhancement: a critical factor for performance of liposomal transdermal drug delivery system

Mechanical characterization of freestanding lipid bilayers with temperature-controlled phase

Coexistence of lipid domains in cell membranes is associated with vital biological processes. Here, we investigate two such membranes: a multi-component membrane composed of DOPC and DPPC lipids with gel and fluid separated domains, and a single component membrane composed of PMPC lipids forming ripples. We characterize their mechanical properties below their melting point, where ordered and disordered regions coexist, and above their melting point, where they are in fluid phase. To conduct these inquiries, we create lipid bilayers in a microfluidic chip interfaced with a heating system and optical tweezers. The chip features a bubble trap and enables high-throughput formation of planar bilayers. Optical tweezers experiments reveal interfacial hydrodynamics (fluid-slip) and elastic properties (membrane tension and bending rigidity) at various temperatures. For PMPC bilayers, we demonstrate a higher fluid slip at the interface in the fluid-phase compared to the ripple phase, while for the DOPC:DPPC mixture, similar fluid slip is measured below and above the transition point. Membrane tension for both compositions increases after thermal fluidization. Bending rigidity is also measured using the forces required to extend a lipid nanotube pushed out of the freestanding membranes. This novel temperature-controlled microfluidic platform opens numerous possibilities for thermomechanical studies on freestanding planar membranes.

Advancing liposome technology for innovative strategies against malaria

This review discusses the potential of liposomes as drug delivery systems for antimalarial therapies. Malaria continues to be a significant cause of mortality and morbidity, particularly among children and pregnant women. Drug resistance due to patient non-compliance and troublesome side effects remains a significant challenge in antimalarial treatment. Liposomes, as targeted and efficient drug carriers, have garnered attention owing to their ability to address these issues. Liposomes encapsulate hydrophilic and/or hydrophobic drugs, thus providing comprehensive and suitable therapeutic drug delivery. Moreover, the potential of passive and active drug delivery enables drug concentration in specific target tissues while reducing adverse effects. However, successful liposome formulation is influenced by various factors, including drug physicochemical characteristics and physiological barriers encountered during drug delivery. To overcome these challenges, researchers have explored modifications in liposome nanocarriers to achieve efficient drug loading, controlled release, and system stability. Computational approaches have also been adopted to predict liposome system stability, membrane integrity, and drug-liposome interactions, improving formulation development efficiency. By leveraging computational methods, optimizing liposomal drug delivery systems holds promise for enhancing treatment efficacy and minimizing side effects in malaria therapy. This review consolidates the current understanding and highlights the potential of liposome strategies against malaria.

Delivery Strategies for Colchicine as a Critical Dose Drug: Reducing Toxicity and Enhancing Efficacy

Colchicine (COL), a widely used natural drug, has potent anti-inflammatory effects; however, as a narrow therapeutic index drug, its clinical application is limited by its serious gastrointestinal adverse effects, and only oral formulations are currently marketed worldwide. Recent studies have shown that transdermal, injection, and oral drug delivery are the three main delivery strategies for COL. This article elaborates on the research progress of different delivery strategies in terms of toxicity reduction and efficacy enhancement, depicting that the transdermal drug delivery route can avoid the first-pass effect and the traumatic pain associated with the oral and injection routes, respectively. Therefore, such a dosage form holds a significant promise that requires the development of further research to investigate effective COL delivery formulations. In addition, the permeation-promoting technologies utilized for transdermal drug delivery systems are briefly discussed. This article is expected to provide scientific ideas and theoretical guidance for future research and the exploration of COL delivery strategies.

Therapeutic strategy of biological macromolecules based natural bioactive compounds of diabetes mellitus and future perspectives: A systematic review

High blood glucose levels are a hallmark of the metabolic syndrome known as diabetes mellitus. More than 600 million people will have diabetes by 2045 as the global prevalence of the disease continues to rise. Contemporary antidiabetic drugs reduce hyperglycemia and its consequences. However, these drugs come with undesirable side effects, so it's encouraging that research into plant extracts and bioactive substances with antidiabetic characteristics is on the rise. Natural remedies are preferable to conventional anti-diabetic drugs since they are safer for the body, more affordable and have fewer potential adverse effects. Biological macromolecules such as liposomes, niosomes, polymeric nanoparticles, solid lipid nanoparticles, nanoemulsions and metallic nanoparticles are explored in this review. Current drug restrictions have been addressed, and the effectiveness of plant-based antidiabetic therapies has enhanced the merits of these methods. Plant extracts' loading capacity and the carriers' stability are the primary obstacles in developing plant-based nanocarriers. Hydrophilic, hydrophobic, and amphiphilic drugs are covered, and a brief overview of the amphipathic features of liposomes, phospholipids, and lipid nanocarriers is provided. Metallic nanoparticles' benefits and attendant risks are highlighted to emphasize their efficiency in treating hyperglycemia. Researchers interested in the potential of nanoparticles loaded with plant extracts as antidiabetic therapeutics may find the current helpful review.

Therapeutic Potential of Nanocarrier-Mediated Delivery of Phytoconstituents for Wound Healing: Their Current Status and Future Perspective

The treatment of wounds is a serious problem all over the world and imposes a huge financial burden on each and every nation. For a long time, researchers have explored wound dressing that speeds up wound healing. Traditional wound dressing does not respond effectively to the wound-healing process as expected. Therapeutic active derived from plant extracts and extracted bioactive components have been employed in various regions of the globe since ancient times for the purpose of illness, prevention, and therapy. About 200 years ago, most medical treatments were based on herbal remedies. Especially in the West, the usage of herbal treatments began to wane in the 1960s as a result of the rise of allopathic medicine. In recent years, however, there has been a resurgence of interest in and demand for herbal medicines for a number of reasons, including claims about their efficacy, shifting consumer preferences toward natural medicines, high costs and negative side effects of modern medicines, and advancements in herbal medicines brought about by scientific research and technological innovation. The exploration of medicinal plants and their typical uses could potentially result in advanced pharmaceuticals that exhibit reduced adverse effects. This review aims to present an overview of the utilization of nanocarriers in plant-based therapeutics, including its current status, recent advancements, challenges, and future prospects. The objective is to equip researchers with a comprehensive understanding of the historical background, current state, and potential future developments in this emerging field. In light of this, the advantages of nanocarriers based delivery of natural wound healing treatments have been discussed, with a focus on nanofibers, nanoparticles, nano-emulsion, and nanogels.

Enhancement of the Transdermal Delivery of Nonsteroidal Anti-inflammatory Drugs Using Liposomes Containing Cationic Surfactants

New hybrid liposomes based on cationic amphiphiles with different structures of the head group (cetyltrimethylammonium bromide (CTAB), 3-hexadecyl-1-hydroxyethylimidazolium bromide (IA-16(OH)), 1-(butylcarbamoyl)oxyethyl-3-hexadecylimidazolium bromide (IAC 16(Bu)), and hexadecylmethylpyrrolidinium bromide (PR-16)) were developed for transdermal administration of nonsteroidal anti-inflammatory drugs. The different surfactant/lipid compositions were studied to obtain stable liposomes with high functionality. The hydrodynamic diameter of cationic liposomes was ∼110 nm. An admixture of cationic surfactants and PC liposomes improves the physicochemical properties of vesicles and transdermal diffusion rate and prolongs the release of drugs. Liposomal diclofenac sodium (DS) and ketoprofen (KP) were tested (using Franz cells) for transdermal penetration. Drug diffusion monitoring for 48 h demonstrated that the maximum DS and KP penetration through the synthetic membranes (Strat-M) is characterized by values of 255 ± 2 and 186 ± 3 μg/cm², respectively. The influence of the surfactant head group on the properties (stability, release profile, permeability) of cationic liposomes was shown for the first time. While the drug specificity is evident for the rate of release, the permeability increases as follows: conventional liposomes < CTAB/PC < PR-16/PC < IAC-16(Bu)/PC < IA-16(OH)/PC for both medicines. The rat paw edema model was used to assess the anti-inflammatory effect of the IA-16(OH)/PC leader formulation in vivo. It was found that liposomal DS and KP are effective for relieving rat paw edema. It should be noted that DS-loaded hybrid liposomes demonstrated the highest therapeutic efficacy compared to conventional vesicles.

A Review on the Delivery of Plant-Based Antidiabetic Agents Using Nanocarriers: Current Status and Their Role in Combatting Hyperglycaemia

Diabetes mellitus is a prevalent metabolic syndrome that is associated with high blood glucose levels. The number of diabetic patients is increasing every year and the total number of cases is expected to reach more than 600 million worldwide by 2045. Modern antidiabetic drugs alleviate hyperglycaemia and complications that are caused by high blood glucose levels. However, due to the side effects of these drugs, plant extracts and bioactive compounds with antidiabetic properties have been gaining attention as alternative treatments for diabetes. Natural products are biocompatible, cheaper and expected to cause fewer side effects than the current antidiabetic drugs. In this review, various nanocarrier systems are discussed, such as liposomes, niosomes, polymeric nanoparticles, nanoemulsions, solid lipid nanoparticles and metallic nanoparticles. These systems have been applied to overcome the limitations of the current drugs and simultaneously improve the efficacy of plant-based antidiabetic drugs. The main challenges in the formulation of plant-based nanocarriers are the loading capacity of the plant extracts and the stability of the carriers. A brief review of lipid nanocarriers and the amphipathic properties of phospholipids and liposomes that encapsulate hydrophilic, hydrophobic and amphiphilic drugs is also described. A special emphasis is placed on metallic nanoparticles, with their advantages and associated complications being reported to highlight their effectiveness for treating hyperglycaemia. The present review could be an interesting paper for researchers who are working in the field of using plant extract-loaded nanoparticles as antidiabetic therapies.

Versatile Encapsulation and Synthesis of Potent Liposomes by Thermal Equilibration

The wide-scale use of liposomal delivery systems is challenged by difficulties in obtaining potent liposomal suspensions. Passive and active loading strategies have been proposed to formulate drug encapsulated liposomes but are limited by low efficiencies (passive) or high drug specificities (active). Here, we present an efficient and universal loading strategy for synthesizing therapeutic liposomes. Integrating a thermal equilibration technique with our unique liposome synthesis approach, co-loaded targeting nanovesicles can be engineered in a scalable manner with potencies 200-fold higher than typical passive encapsulation techniques. We demonstrate this capability through simultaneous co-loading of hydrophilic and hydrophobic small molecules and targeted delivery of liposomal Doxorubicin to metastatic breast cancer cell line MDA-MB-231. Molecular dynamic simulations are used to explain interactions between Doxorubicin and liposome membrane during thermal equilibration. By addressing the existing challenges, we have developed an unparalleled approach that will facilitate the formulation of novel theranostic and pharmaceutical strategies.

Optimization of phospholipid chemistry for improved lipid nanoparticle (LNP) delivery of messenger RNA (mRNA)

Lipid nanoparticles (LNPs) have been established as an essential platform for nucleic acid delivery. Efforts have led to the development of vaccines that protect against SARS-CoV-2 infection using LNPs to deliver messenger RNA (mRNA) coding for the viral spike protein. Out of the four essential components that comprise LNPs, phospholipids represent an underappreciated opportunity for fundamental and translational study. We investigated this avenue by systematically modulating the identity of the phospholipid in LNPs with the goal of identifying specific moieties that directly enhance or hinder delivery efficacy. Results indicate that phospholipid chemistry can enhance mRNA delivery by increasing membrane fusion and enhancing endosomal escape. Phospholipids containing phosphoethanolamine (PE) head groups likely increase endosomal escape due to their fusogenic properties. Additionally, it was found that zwitterionic phospholipids mainly aided liver delivery, whereas negatively charged phospholipids changed the tropism of the LNPs from liver to spleen. These results demonstrate that the choice of phospholipid plays a role intracellularly by enhancing endosomal escape, while also driving organ tropism in vivo. These findings were then applied to Selective Organ Targeting (SORT) LNPs to manipulate and control spleen-specific delivery. Overall, selection of the phospholipid in LNPs provides an important handle to design and optimize LNPs for improved mRNA delivery and more effective therapeutics.

Exploring the membrane fluidity of phenyl boronic acid functionalized polymersomes using the FRAP technique and their application in the pH-sensitive release of curcumin

FRAP study to examine alterations in the membrane fluidity of functionalized polymersomes and pH responsive targeted delivery of curcumin.

Preparation and characterizations of glyceryl oleate ufasomes of terbinafine hydrochloride: a novel approach to trigger Candida albicans fungal infection

Background

Worldwide fungal infection cases are increasing by leaps and bounds. The patients who are immunocompromised, i.e., cancer and AIDS, are more susceptible to different types of fungal infections like cutaneous candidiasis and its associate infections. The available treatment for such a disease is creams, gels, etc. However, due to the lack of penetrability and higher systematic absorption, these formulations have reported many side effects. To overcome such challenges, various novel drug delivery systems were introduced. The present research focused on the preparation of glyceryl oleate ufasomes of terbinafine hydrochloride using the film hydration method.

Result

The prepared formulations were characterized for globular size (nm), zeta potential (mV), PDI, morphological characteristics, thermal behavior, in vitro drug release, in vitro antifungal activity, and in vitro skin permeation retention studies. After suitable formulation optimization using thin-film hydration method, 3:7 drug to glyceryl oleate ratio, UF3 formulation was found to produce higher drug entrapment efficacy (52.45 ± 0.56%), stable anionic zeta potential (− 33.37 ± 0.231 mV), desired globular size (376.5 ± 0.42 nm), and decent polydispersity index (0.348 ± 0.0345). Diffusion-controlled and zero-order sustained release profile was observed in the optimized UF3 batch. From the 5 days in vitro antifungal activity studies, it confirmed that UF3 ufasomes possessed good applicability in more prolonged therapy.

Conclusion

From the current investigation, it can be concluded that glyceryl oleate ufasomes of terbinafine hydrochloride could be an excellent approach to treat topical fungal infections.

Response Surface Optimization of Ultra-Elastic Nanovesicles Loaded with Deflazacort Tailored for Transdermal Delivery: Accentuated Bioavailability and Anti-Inflammatory Efficacy

PURPOSE

The aim of the present study was to develop deflazacort (DFZ) ultra-elastic nanovesicles (UENVs) loaded gel for topical administration to evade gastrointestinal adverse impacts accompanying DFZ oral therapy.

METHODS

UENVs were elaborated according to D-optimal mixture design employing different edge activators as Span-60, Tween-85 and sodium cholate which were incorporated into the nanovesicles to improve the deformability of vesicles bilayer. DFZ-UENVs were formulated by thin-film hydration technique followed by characterization for different parameters including entrapment efficiency (%EE), particle size, in vitro release and ex vivo permeation studies. The composition of the optimized DFZ-UENV formulation was found to be DFZ (10 mg), Span-60 (30 mg), Tween-85 (30 mg), sodium cholate (3.93 mg), L-α phosphatidylcholine (60 mg) and cholesterol (30 mg). The optimum formulation was incorporated into hydrogel base then characterized in terms of physical parameters, in vitro drug release, ex vivo permeation study and pharmacodynamics evaluation. Finally, pharmacokinetic study in rabbits was performed via transdermal application of UENVs gel in comparison to oral drug.

RESULTS

The optimum UENVs formulation exhibited %EE of 74.77±1.33, vesicle diameter of 219.64±2.52 nm, 68.88±1.64% of DFZ released after 12 h and zeta potential of -55.57±1.04 mV. The current work divulged successful augmentation of the bioavailability of DFZ optimum formulation by about 1.37-fold and drug release retardation compared to oral drug tablets besides significant depression of edema, cellular inflammation and capillary congestion in carrageenan-induced rat paw edema model.

CONCLUSION

The transdermal DFZ-UENVs can achieve boosted bioavailability and may be suggested as an auspicious non-invasive alternative platform for oral route.

Dermal pharmacokinetics of rivastigmine-loaded liposomes: an ex vivo-in vivo correlation study

The aim of the present study was to develop a topical liposomal formulation as a transdermal delivery of rivastigmine for the treatment of Alzheimer's disease as an alternative to the oral dosage form and to achieve smooth continuous drug delivery and maintain plasma levels within the therapeutic window. Rivastigmine-loaded liposomes were prepared by a thin layer hydration technique that was applied in ex vivo-in vivo correlation study. Permeability parameters through rat skin in ex vivo study and pharmacokinetic parameters in the in vivo study were evaluated. The ex vivo permeation study showed that liposomes provided steady-state flux 0.11 ± 0.01 mg/cm.h that were more than 2-fold the aqueous control. In the in vivo experiments, after topical application of optimized rivastigmine liposomes, the C_max 208 ng/ml and AUC_0-24 3605 (ng.h/ml) were also significantly higher than the control group (both p < 0.01). A point-to-point significant linear correlation was found between ex vivo and in vivo parameters, meaning in vivo pharmacokinetic parameters can be predicted by ex vivo permeation parameters. These data suggest that a liposomal formulation could be an effective carrier to enhance rivastigmine permeation through the skin and maintain plasma levels within the therapeutic window.

Clinical use of Capilen, a liposomal cream based on fresh plant extracts enriched with omega fatty acids

The skin is the largest organ in the human body; beyond its regulatory and sensory roles, it is meant to protect and act like a barrier against foreign matter. Products intended to restore the skin health should reintegrate the structure of the stratum corneum in which the corneocytes are surrounded by the intercellular lipid lamellae that maintain both corneum integrity and skin permeability barrier. Capilen is a specific liposomal formulation based on a technology through which highly concentrated fresh plant extracts are conveyed into a jelly-like liposomal vehicle and combined with plant-derived omega-3, -6, -7, and -9 fatty acids, phospholipids, and precursors of ceramides. Its components have been widely investigated and produced clinical benefits in atopic dermatitis, bedsores, scars, inflammatory lesions of the skin, and generally whenever signs of xerosis cutis were present. Liposomes contribute to restore the surface lipid layer of the skin and to deliver substances in the activity site. This liposomal cream was proven to limit and delay the occurrence of radiodermatitis in breast cancer patients, and as an add-on provided complete healing of bedsore lesions in geriatric subjects.

Vesicles: Potential nano carriers for the delivery of skin cosmetics

In the present scenario, consumers are searching for personal care products that supply multiple benefits with minimal efforts. The outcome has been the introduction of nanotechnology-based cosmetic products that are safe to use and results driven. Some topical cosmetics can act efficaciously when they reach their target sites present in the deeper layers of the skin. The main problem with delivering active ingredients across the skin is the barrier function of the skin. Therefore, to get the maximum benefit from cosmetic products and to overcome the problems associated with their skin penetration, scientists are investigating various strategies to overcome these barrier properties. Vesicular carriers have been claimed to improve the topical delivery of active ingredients. This review offers a brief overview of current approaches in the research and development of vesicular carriers to improve the delivery and performance of active ingredients present in the cosmetics.

Pharmaceutical liposomal drug delivery: a review of new delivery systems and a look at the regulatory landscape

Liposomes were the first nanoscale drug to be approved for clinical use in 1995. Since then, the technology has grown considerably, and pioneering recent work in liposome-based delivery systems has brought about remarkable developments with significant clinical implications. This includes long-circulating liposomes, stimuli-responsive liposomes, nebulized liposomes, elastic liposomes for topical, oral and transdermal delivery and covalent lipid-drug complexes for improved drug plasma membrane crossing and targeting to specific organelles. While the regulatory bodies' opinion on liposomes is well-documented, current guidance that address new delivery systems are not. This review describes, in depth, the current state-of-the-art of these new liposomal delivery systems and provides a critical overview of the current regulatory landscape surrounding commercialization efforts of higher-level complexity systems, the expected requirements and the hurdles faced by companies seeking to bring novel liposome-based systems for clinical use to market.

A Comparison of the Penetration and Permeation of Caffeine into and through Human Epidermis after Application in Various Vesicle Formulations

<b><i>Background/Aims:</i></b> A range of vesicles is now widely used to carry various solutes into and through the epidermis. These usually have the active solute encapsulated within and may be modified to confer flexibility and skin penetration enhancement. Here, we compared the ability of five different vesicle systems to deliver a model hydrophilic drug, caffeine, into and through excised human skin. <b><i>Methods:</i></b> In addition to lipids, the vesicle excipients included eucalyptol or oleic acid as penetration enhancers, and decyl polyglucoside as a non-ionic surfactant. Vesicle particle sizes ranged between 135 and 158 nm, and caffeine encapsulation efficiencies were between 46 and 66%. Caffeine penetration and permeation were measured using high-performance liquid chromatography. <b><i>Results:</i></b> We found that niosomes, which are liposomes containing a non-ionic surfactant, and transferosomes (ultraflexible vesicles) showed significantly greater penetration into the skin and permeation across the stratum corneum. Significant enhancement of caffeine penetration into hair follicles was found for transferosomes and those liposomes containing oleic acid. <b><i>Conclusions:</i></b> We conclude that targeted delivery of the hydrophilic drug caffeine into the skin compartments can be modified using optimized vesicular formulations.

Phosphatidylcholine liposomes as carriers to improve topical ascorbic acid treatment of skin disorders

Liposomes have been intensively investigated as carriers for different applications in dermatology and cosmetics. Ascorbic acid has potent antioxidant and anti-inflammatory properties preventing photodamage of keratinocytes; however, due to its instability and low skin penetration, an appropriate carrier is mandatory to obtain desirable efficacy. The present work investigates the ability of a specific ascorbate phosphatidylcholine (PC) liposome to overcome the barrier of the stratum corneum and deliver the active agent into the dermis to prevent photodamage. Abdominal skin from ten patients was used. Penetration of PC liposomes was tested ex vivo in whole skin, epidermis, and dermis by means of fluorescein and sodium ascorbate. Histology and Franz diffusion cells were used to monitor the percutaneous absorption. Ultraviolet (UV)-high performance liquid chromatography was used to analyze diffusion of sodium ascorbate through the different skin layers, while spectrofluorimetry and fluorescent microscopy were used for fluorescein monitoring. UVA/UVB irradiation of whole skin was applied to analyze the antioxidant capacity by Trolox assay and anti-inflammatory effects by tumor necrosis factor alpha and interleukin 1 beta enzyme-linked immunoassay. PC liposomal formulation improved skin penetration of fluorescein and ascorbate. Fluorescein PC liposomes showed better diffusion through epidermis than dermis while ascorbate liposomes showed better diffusion through the dermis than the epidermis. Ascorbate PC liposomes showed preventive antioxidant and anti-inflammatory properties on whole human skin irradiated with UVA/UVB. In summary, ascorbate PC liposomes penetrate through the epidermis and allow nonstable hydrophilic active ingredients reach epidermis and dermis preventing skin photodamage.