Ascorbyl palmitate vesicles (Aspasomes): formation, characterization and applications

Liposome bilayer stability: emphasis on cholesterol and its alternatives

Liposomes are spherical lipidic nanocarriers composed of natural or synthetic phospholipids with a hydrophobic bilayer and aqueous core, which are arranged into a polar head and a long hydrophobic tail, forming an amphipathic nano/micro-particle. Despite numerous liposomal applications, their use encounters many challenges related to the physicochemical properties strongly affected by their constituents, colloidal stability, and interactions with the biological environment. This review aims to provide a perspective and a clear idea about the main factors that regulate the liposomes' colloidal and bilayer stability, emphasising the roles of cholesterol and its possible alternatives. Moreover, this review will analyse strategies that offer possible approaches to provide more stable in vitro and in vivo liposomes with enhanced drug release and encapsulation efficiencies.

A Comprehensive Review on Niosomes as a Tool for Advanced Drug Delivery

Over the past few decades, advancements in nanocarrier-based therapeutic delivery have been significant, and niosomes research has recently received much interest. The self-assembled nonionic surfactant vesicles lead to the production of niosomes. The most recent nanocarriers, niosomes, are self-assembled vesicles made of nonionic surfactants with or without the proper quantities of cholesterol or other amphiphilic molecules. Because of their durability, low cost of components, largescale production, simple maintenance, and high entrapment efficiency, niosomes are being used more frequently. Additionally, they enhance pharmacokinetics, reduce toxicity, enhance the solubility of poorly water-soluble compounds, & increase bioavailability. One of the most crucial features of niosomes is their controlled release and targeted diffusion, which is utilized for treating cancer, infectious diseases, and other problems. In this review article, we have covered all the fundamental information about niosomes, including preparation techniques, niosomes types, factors influencing their formation, niosomes evaluation, applications, and administration routes, along with recent developments.

Organic and Biogenic Nanocarriers as Bio-Friendly Systems for Bioactive Compounds' Delivery: State-of-the Art and Challenges

"Green" strategies to build up novel organic nanocarriers with bioperformance are modern trends in nanotechnology. In this way, the valorization of bio-wastes and the use of living systems to develop multifunctional organic and biogenic nanocarriers (OBNs) have revolutionized the nanotechnological and biomedical fields. This paper is a comprehensive review related to OBNs for bioactives' delivery, providing an overview of the reports on the past two decades. In the first part, several classes of bioactive compounds and their therapeutic role are briefly presented. A broad section is dedicated to the main categories of organic and biogenic nanocarriers. The major challenges regarding the eco-design and the fate of OBNs are suggested to overcome some toxicity-related drawbacks. Future directions and opportunities, and finding "green" solutions for solving the problems related to nanocarriers, are outlined in the final of this paper. We believe that through this review, we will capture the attention of the readers and will open new perspectives for new solutions/ideas for the discovery of more efficient and "green" ways in developing novel bioperformant nanocarriers for transporting bioactive agents.

Lipid Nano-System Based Topical Drug Delivery for Management of Rheumatoid Arthritis: An Overview

The overall purpose of rheumatoid arthritis (RA) treatment is to give symptomatic alleviation; there is no recognized cure for RA. Frequent use of potent drugs like non-steroidal anti-inflammatory drugs (NSAIDs) and disease-modifying antirheumatic drugs (DMARDs), lead to various adverse effects and patient compliance suffers. On the other hand, there are many drawbacks associated with traditional methods, such as high first pass, high clearance rate, and low bioavailability. Drug administration through the skin can be a promising alternative to cope with these drawbacks, increasing patient compliance and providing site-specific action. The stratum corneum, the uppermost non-viable epidermal layer, is one of the primary limiting barriers to skin penetration. Various nanocarrier technologies come into play as drug vehicles to help overcome these barriers. The nanocarrier systems are biocompatible, stable, and have a lower cytotoxic impact. The review discusses several lipid-based nanocarrier systems for anti-rheumatic medicines for topical administration it also discusses in-vivo animal models for RA and provides information on patents granted.

Niosome as an Effective Nanoscale Solution for the Treatment of Microbial Infections

Numerous disorders go untreated owing to a lack of a suitable drug delivery technology or an appropriate therapeutic moiety, particularly when toxicities and side effects are a major concern. Treatment options for microbiological infections are not fulfilled owing to significant adverse effects or extended therapeutic options. Advanced therapy options, such as active targeting, may be preferable to traditional ways of treating infectious diseases. Niosomes can be defined as microscopic lamellar molecules formed by a mixture of cholesterol, nonionic surfactants (alkyl or dialkyl polyglycerol ethers), and sometimes charge-inducing agents. These molecules comprise both hydrophilic and hydrophobic moieties of varying solubilities. In this review, several pathogenic microbes such as Staphylococcus aureus, Pseudomonas aeruginosa, Klebsiella pneumoniae, Plasmodium, Leishmania, and Candida spp. have been evaluated. Also, the development of a proper niosomal formulation for the required application was discussed. This review also reviews that an optimal formulation is dependent on several aspects, including the choice of nonionic surfactant, fabrication process, and fabrication parameters. Finally, this review will give information on the effectiveness of niosomes in treating acute microbial infections, the mechanism of action of niosomes in combating microbial pathogens, and the advantages of using niosomes over other treatment modalities.

Diversifying the skin cancer-fighting worthwhile frontiers: How relevant are the itraconazole/ascorbyl palmitate nanovectors?

Fighting malignant neoplasms via repurposing existing drugs could be a welcome move for prosperous cancer remediations. In the current work, nanovehiculation and optimization of the repositioned itraconazole (ITZ) utilizing ascorbyl palmitate (AP) aspasomes would be an auspicious approach. Further, the optimized aspasomes were incorporated in a cream and tracked for skin deposition. The in vivo efficacy of aspasomal cream on mice subcutaneous Ehrlich carcinoma model was also assessed. The optimized aspasomes revealed nano size (67.83 ± 6.16 nm), negative charge (-79.40 ± 2.23 mV), > 95% ITZ entrapment and high colloidal stability. AP yielded substantial antioxidant capacity and pushed the ITZ cytotoxicity forward against A431 cells (IC₅₀ = 5.3±0.27 μg/mL). An appealing privilege was the aspasomal cream that corroborated spreadability, contemplated skin permeation and potentiated in vivo anticancer competence, reflected in 62.68% reduction in the tumor weight. Such synergistic tumor probes set the foundation for futuristic clinical translation and commercialization.

Assessment of antifungal efficacy of itraconazole loaded aspasomal cream: comparative clinical study

Topical conveyance of antifungal agents like itraconazole ITZ has been giving good grounds for expecting felicitous antifungal medicines. The defiance of topical delivery of this poorly water soluble and high-molecular-weight drug, however, mightily entail an adequate vehiculation. ITZ aspasomes, newer antioxidant generation of liposomes, have been designed and enclosed in a cream to ameliorate skin deposition. The proposed creams containing non-formulated ITZ or encapsulated in aspasomes (0.1% or 0.5%) were topically applied in patients with diagnosed diaper dermatitis complicated by candidiasis, tinea corporis (TC), and tinea versicolor (TVC). Placebos (void aspasomal cream and cream base) were also utilized. The obtained results for diaper rash revealed that aspasomal cream (0.5% ITZ) was eminent with respect to complete cure and negative candida culture after 10-day therapy relative to counterparts containing 0.1% ITZ aspasomes or non-formulated ITZ (0.1% and 0.5%). For tinea, the same trend was manifested in terms of ‘cleared’ clinical response in 90% of patients and absence of fungal elements after 4-week treatment. Relative to non-formulated ITZ, ITZ aspasomal cream was endorsed to be auspicious especially when ITZ concentration was lowered to half commercially available cream concentration (1%), pushing further exploitation in other dermal fungal infections.

Synthesis and In Vitro Characterization of Ascorbyl Palmitate-Loaded Solid Lipid Nanoparticles

Antitumor applications of ascorbic acid (AA) and its oxidized form dehydroascorbic acid (DHA) can be quite challenging due to their instability and sensitivity to degradation in aqueous media. To overcome this obstacle, we have synthesized solid lipid nanoparticles loaded with ascorbyl palmitate (SLN-AP) with variations in proportions of the polymer Pluronic F-68. SLNs were synthesized using the hot homogenization method, characterized by measuring the particle size, polydispersity, zeta potential and visualized by TEM. To investigate the cellular uptake of the SLN, we have incorporated coumarin-6 into the same SLN formulation and followed their successful uptake for 48 h. We have tested the cytotoxicity of the SLN formulations and free ascorbate forms, AA and DHA, on HEK 293 and U2OS cell lines by MTT assay. The SLN-AP in both formulations have a cytotoxic effect at lower concentrations when compared to ascorbate applied the form of AA or DHA. Better selectivity for targeting tumor cell line was observed with 3% Pluronic F-68. The antioxidative effect of the SLN-AP was observed as early as 1 h after the treatment with a small dose of ascorbate applied (5 µM). SLN-AP formulation with 3% Pluronic F-68 needs to be further optimized as an ascorbate carrier due to its intrinsic cytotoxicity.

Multidrug Idebenone/Naproxen co-loaded Aspasomes for a Significant In VivoAnti-Inflammatory Activity

The use of proper nanocarriers for dermal and transdermal delivery of anti‐inflammatory drugs recently gained several attentions in the scientific community because they pass intact and accumulate payloads in the deepest layers of skin tissue. Ascorbyl palmitate‐based vesicles (aspasomes) can be considered a promising nanocarrier for dermal and transdermal delivery due to their skin whitening properties and suitable delivery of payloads through the skin. The aim of this study was the synthesis of multidrug Idebenone/naproxen co‐loaded aspasomes for the development of an effective anti‐inflammatory nanomedicine. Aspasomes had suitable physicochemical properties and were safe in vivo if topically applied on human healthy volunteers. Idebenone/naproxen co‐loaded aspasomes demonstrated an increased therapeutic efficacy of payloads compared to the commercially available Naprosyn® gel, with a rapid decrease of chemical‐induced erythema on human volunteers. These promising results strongly suggested a potential application of Idebenone/naproxen multidrug aspasomes for the development of an effective skin anti‐inflammatory therapy.

The Optimized Delivery of Triterpenes by Liposomal Nanoformulations: Overcoming the Challenges

The last decade has witnessed a sustained increase in the research development of modern-day chemo-therapeutics, especially for those used for high mortality rate pathologies. However, the therapeutic landscape is continuously changing as a result of the currently existing toxic side effects induced by a substantial range of drug classes. One growing research direction driven to mitigate such inconveniences has converged towards the study of natural molecules for their promising therapeutic potential. Triterpenes are one such class of compounds, intensively investigated for their therapeutic versatility. Although the pharmacological effects reported for several representatives of this class has come as a well-deserved encouragement, the pharmacokinetic profile of these molecules has turned out to be an unwelcomed disappointment. Nevertheless, the light at the end of the tunnel arrived with the development of nanotechnology, more specifically, the use of liposomes as drug delivery systems. Liposomes are easily synthesizable phospholipid-based vesicles, with highly tunable surfaces, that have the ability to transport both hydrophilic and lipophilic structures ensuring superior drug bioavailability at the action site as well as an increased selectivity. This study aims to report the results related to the development of different types of liposomes, used as targeted vectors for the delivery of various triterpenes of high pharmacological interest.

A Comprehensive Review of Therapeutic Approaches Available for the Treatment of Dermatitis

BACKGROUND

Dermatitis or eczema is a prevalent skin disorder worldwide and is also very common as a pediatric inflammatory skin disorder. Its succession gets worse with the multiple comorbidities which exhibit mechanisms that are poorly understood. Its management further becomes a challenge due to the limited effective treatment options available. However, the Novel Drug Delivery Systems (NDDS) along with new targeting strategies can easily bypass the issues associated with dermatitis management. If we compare the active constituents against phytoconstituents effective against dermatitis then phytoconstituents can be perceived to be more safe and gentle.

OBJECTIVE

Administration of NDDS of plant extract or actives displays improved absorption behavior, which helps them to permeate through lipid-rich biological membrane leading to increased bioavailability. The newer efficient discoveries related to eczema can face various exploitations. This can be intervened by the subjection of patent rights, which not only safeguard the novel works of individual(s) but also give them the opportunity to share details of their inventions with people globally.

CONCLUSION

The present review focuses on the available research about the use of nanoformulations in the topical delivery. It further elaborates the use of different animal models as the basis to characterize the different features of dermatitis. The review also highlights the recent nanoformulations which have the ability to amplify the delivery of active agents through their incorporation in transfersomes, ethosomes, niosomes or phytosomes, etc.

Functionalized niosomes as a smart delivery device in cancer and fungal infection

Various diseases remain untreated due to lack of suitable therapeutic moiety or a suitable drug delivery device, especially where toxicities and side effects are the primary reason for concern. Cancer and fungal infections are diseases where treatment schedules are not completed due to severe side effects or lengthy treatment protocols. Advanced treatment approaches such as active targeting and inhibition of angiogenesis may be preferred method for the treatment for malignancy over the conventional method. Niosomes may be a better alternative drug delivery carrier for various therapeutic moieties (either hydrophilic or hydrophobic) and also due to ease of surface modification, non-immunogenicity and economical. Active targeting approach may be done by targeting the receptors through coupling of suitable ligand on niosomal surface. Moreover, various receptors (CD44, folate, epidermal growth factor receptor (EGFR) & Vascular growth factor receptor (VGFR)) expressed by malignant cells have also been reviewed. The preparation of suitable niosomal formulation also requires considerable attention, and its formulation depends upon various factors such as selection of non-ionic surfactant, method of fabrication, and fabrication parameters. A combination therapy (dual drug and immunotherapy) has been proposed for the treatment of fungal infection with special consideration for surface modification with suitable ligand on niosomal surface to sensitize the receptors (C-type lectin receptors, Toll-like receptors & Nucleotide-binding oligomerization domain-like receptors) present on immune cells involved in fungal immunity. Certain gene silencing concept has also been discussed as an advanced alternative treatment for cancer by silencing the mRNA at molecular level using short interfering RNA (si-RNA).

An Engineered Specificity of Anti-Neoplastic Agent Loaded Magnetic Nanoparticles for the Treatment of Breast Cancer

Nanoparticles have gained increased attention due to the prospection of drug delivery at target sites, thus limiting the systemic effects of the drugs. Their efficiency was further improved by adding special carriers such as magnetite (Fe3O4). It is one of the extensively used oxides of iron for both pharmaceutical and biomedical applications owing to its ease of preparation and biocompatibility. In this work, Gemcitabine magnetic nanoparticles were prepared using Fe3O4 and chitosan as the primary ingredients. Optimization was accomplished by Box-Behnken Design and factor interactions were evaluated. The desirability function approach was made to enhance the formulation concerning particle size, polydispersity index, and zeta potential. Based on this, optimized magnetic nanoparticles (O-MNP) were formulated with 300 mg of Fe3O4, 297.7 mg of chitosan, and a sonication time of 2.4 h, which can achieve the prerequisites of the target formulation. All other in vitro parameters were found to be following the requirement. In vitro cytotoxic studies for O-MNP were performed using cell cultures of breast cancer (MCF-7), leukemia (THP-1), prostate cancer (PC-3), and lung cancer (A549). O-MNP showed maximum inhibition growth with MCF-7 cell lines rather than other cell lines. The data observed here demonstrates the potential of magnetic nanoparticles of gemcitabine in treating breast cancers.

Biomimetic pH/lipase dual responsive vitamin-based solid lipid nanoparticles for on-demand delivery of vancomycin

In this study, ascorbyl tocopherol succinate (ATS) was designed, synthesized and characterized via FT-IR, HR-MS, H¹ NMR and C¹³ NMR, to simultaneously confer biomimetic and dual responsive properties of an antibiotic nanosystem to enhance their antibacterial efficacy and reduce antimicrobial resistance. Therefore, an in silico-aided design (to mimic the natural substrate of bacterial lipase) was employed to demonstrate the binding potential of ATS to lipase (-32.93 kcal/mol binding free energy (ΔG_bind) and bacterial efflux pumps blocking potential (NorA ΔG_bind: -37.10 kcal/mol, NorB ΔG_bind: -34.46 kcal/mol). ATS bound stronger to lipase than the natural substrate (35 times lower Kd value). The vancomycin loaded solid lipid nanoparticles (VM-ATS-SLN) had a hydrodynamic diameter, zeta potential, polydispersity index and entrapment efficiency of 106.9 ± 1.4 nm, -16.5 ± 0.93 mV, 0.11 ± 0.012 and 61.9 ± 1.31%, respectively. In vitro biocompatibility studies revealed VM-ATS-SLN biosafety and non-haemolytic activity. Significant enhancement in VM release was achieved in response to acidified pH and lipase enzyme, compared to controls. VM-ATS-SLN showed enhanced sustained in vitro antibacterial activity for 5 days, 2-fold greater MRSA biofilm growth inhibition and 3.44-fold reduction in bacterial burden in skin infected mice model compared to bare VM. Therefore, ATS shows potential as a novel multifunctional adjuvant for effective and targeted delivery of antibiotics.

Mesoporous silica integrated with Fe3O4 and palmitoyl ascorbate as a new nano-Fenton reactor for amplified tumor oxidation therapy

Co-delivery of H2O2-generating agent and catalyst via a nano-Fenton reactor to the tumor acidic microenvironment for amplified tumor oxidation therapy has been widely studied. However, high side effects and low efficiency remain the limitations of the design and development of this process. Herein, a new nano-Fenton reactor in which mesoporous silica is integrated with Fe3O4 and palmitoyl ascorbate (Fe3O4@SiO2-PA) was designed, with the product exhibiting good dispersion, stability, uniformity and consistent spectral characteristics. The results show that Fe3O4@mSiO2-PA successfully enters cancer cells, significantly inhibits HeLa cells and 3D tumor spheroid growth in vitro via the induction of apoptosis. Meanwhile, Fe3O4@mSiO2-PA administration in vivo markedly suppresses HeLa tumor xenografts growth via the induction of apoptosis, followed by caspase-3 activation and cytochrome C release. Further investigation revealed that Fe3O4@mSiO2-PA causes enhanced production of reactive oxygen species (ROS), which subsequently triggers DNA damage and causes dysfunction of the MAPK and PI3K/AKT pathways. Importantly, Fe3O4@mSiO2-PA shows few side effects and good biocompatibility in vivo. Taken together, these results suggest that Fe3O4@mSiO2-PA inhibits HeLa cell growth in vitro and in vivo by triggering enhanced oxidative damage and regulating multiple signal pathways. Our findings validate the rational design that mesoporous silica integrated with Fe3O4 and palmitoyl ascorbate can act as a new nano-Fenton reactor for amplified tumor oxidation therapy.

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.

Mometasone furoate-loaded aspasomal gel for topical treatment of psoriasis: formulation, optimization, in vitro and in vivo performance

BACKGROUND

Present investigation was aimed to develop aspasomal gel of Mometasone Furoate for the treatment of Psoriasis that are biologically active and deliver drug at controlled rate and decrease dosing frequency.

METHODS

The vesicles were fabricated using film hydration method and optimized using 32 factorial Design. Prepared formulations were evaluated for percent drug loading, vesicle size, Zeta potential, polydispersity index and morphological studies. Gel was prepared using carbopol by loading optimized drug loaded asposomes and was evaluated for drug content, pH, viscosity and spreadability. The drug release study from the gel was done using dialysis membrane and goat skin. Anti- oxidant potency of the prepared aspasomal gel was determined by Ferric Reducing Assay whereas, in-vivo performance for inflammation and skin irritation was carried out using Wistar rats.

RESULTS

Optimized aspasomes demonstrated desired properties for entrapment efficiency (74.72 ± 1.8), vesicle size (282.9 ± 1.7), polydispersity index (0.2), zeta potential (-20.2 mV) with spherical shape. The results recorded for drug release from the optimized aspasomal gel exhibited sustained release (24h) compared to the marketed cream (5h). Depot formation of Mometasone furoate loaded aspasomal gel in the epidermis was confirmed by ex vivo skin penetration study by using fluorescent marker. In-vivo study revealed no any irritation and inflammation to the skin promoting drug delivery system to treat psoriasis.

CONCLUSION

In conclusion, Mometasone furoate loaded aspasomal gel releases the drug for longer duration of time and reduce dosing frequency, providing the new dimension for the treatment of psoriasis.

Preparation of Barije (Ferula gummosa) Essential Oil-Loaded Liposomes and Evaluation of Physical and Antibacterial Effect on Escherichia coli O157:H7

ABSTRACT

The aim of this study was to load liposomes with Barije (Ferula gummosa) essential oil (EO) and to evaluate their physical and antibacterial properties. Liposomes were produced with specific ratios of lecithin/cholesterol by thin-film hydration and sonication. The chemical composition of the EO was analyzed by gas chromatography and mass spectroscopy. The physical properties of the liposomes (particle size, polydispersity index, zeta potential, and encapsulation efficiency) were evaluated. The antimicrobial effects of these liposomes against Escherichia coli O157:H7 were determined based on the MIC and disk diffusion results. The effect of subinhibitory concentrations (sub-MICs) of EO against the growth of the bacterium over 24 h was evaluated before and after encapsulation. The major components of EO were β-pinene (60.84%) and α-pinene (9.14%). The mean liposome radius of EO-loaded liposomes was 74.27 to 99.93 nm, which was significantly different from that of the empty liposomes (138.76 nm) (P < 0.05). Addition of cholesterol to the lecithin bilayer increased the particle size and reduced the encapsulation efficiency (P < 0.05). The electrostatic stability of the empty liposomes was improved by adding cholesterol, but when the EO was replaced in the liposomes, there was no significant change in electrostatic stability of liposomes with cholesterol (P < 0.05). MICs were 14.5 μg/mL for the EO-loaded nanoliposomes containing 30 mg of lecithin and 30 mg of cholesterol and 10 μg/mL for nonencapsulated EO. This trend was confirmed by measuring the inhibition zone diameter. Sub-MICs of liposomal EO (containing 60 mg of lecithin) decreased bacterial levels to a greater degree than did free EO, especially at 50 and 75% of the MIC.

HIGHLIGHTS

Cosm-nutraceutical nanovesicles for acne treatment: Physicochemical characterization and exploratory clinical experimentation

The full exploration of the 'nutraceuticals' therapeutic potential in cosmetics has been hindered by their poor stratum corneum permeation. Therefore, the aim of the present study was to formulate a nutraceutical; quercetin, in novel vitamin C based nanovesicles (aspasomes), and to explore their beneficial effects in the treatment of acne. Aspasomes were characterized for their particle size, zeta potential, entrapment efficiency (EE%), 3-months storage stability, skin deposition/permeation, antioxidant potential, and morphology. Aspasomes antibacterial efficacy on Propionibacterium acnes using the zone of inhibition assay was also tested, whilst their safety on skin fibroblastic cells was assessed in vitro using 3T3 CCL92 cell lines. An exploratory clinical trial was conducted in acne patients, and the percentage reduction of inflammatory, non-inflammatory and total acne lesions was taken as the evaluation criterion. Results revealed that quercetin-loaded aspasomes displayed a desirable nanometer size (125-184 nm), negative charge with good storage stability, and high skin deposition reaching 40%. Aspasomes managed to preserve the antioxidant activity of quercetin, and exhibited a significantly higher antibacterial effect (15 ± 1.53 mm) against Propionibacterium acnes than quercetin alone (8.25 ± 2.08 mm), and were safe on skin fibroblastic cells. Upon clinical examination in 20 acne patients (14 females, 6 males), quercetin aspasomes exhibited reduction percentages of 77.9%, 11.8% and 55.3% for inflammatory lesions, comedones and total lesions respectively. This opens vast applications of the presented formulation in the treatment of other oxidative skin diseases, and delineates the nutraceuticals and nanoformulations prepared from natural materials as promising dermatological treatment modes.

Development of tizanidine loaded aspasomes as transdermal delivery system: ex-vivo and in-vivo evaluation

New generation of amphiphilic vesicles known as aspasomes were investigated as potential carriers for transdermal delivery of tizanidine (TZN). Using full factorial design, an optimal formulation was developed by evaluating the effects of selected variables on the properties of the vesicles with regards to entrapment efficiency, vesicle size and cumulative percentage released. The optimal formula (TZN-AS 6) consisting of 20 mg TZN, 50 mg ascorbyl palmitate (AP), 50 mg cholesterol (CH) and 50 mg Span 60, represented well dispersed spherical vesicles in the nanorange sizes and exhibited excellent stability under different storage conditions. Ex-vivo permeation studies using excised rat skin showed a 4.4-fold increase of the steady state flux in comparison to the unformulated drug (p < 0.05). The pharmacokinetic parameters obtained from the in-vivo study using Wistar rats, showed that the bioavailability of TZN was enhanced significantly (p < 0.05) when compared to the oral market product of TZN, Sirdalud^®. Moreover, skin irritancy tests confirmed that the vesicles were non-invasive and safe for the skin. Based on the results obtained, the optimised aspasomes formula represents a promising Nano platform for TZN to be administered transdermally, thus improving the therapeutic efficacy of this important muscle relaxant.

Recent advances in non-ionic surfactant vesicles (niosomes): Fabrication, characterization, pharmaceutical and cosmetic applications

Development of nanocarriers for drug delivery has received considerable attention due to their potential in achieving targeted delivery to the diseased site while sparing the surrounding healthy tissue. Safe and efficient drug delivery has always been a challenge in medicine. During the last decade, a large amount of interest has been drawn on the fabrication of surfactant-based vesicles to improve drug delivery. Niosomes are self-assembled vesicular nano-carriers formed by hydration of non-ionic surfactant, cholesterol or other amphiphilic molecules that serve as a versatile drug delivery system with a variety of applications ranging from dermal delivery to brain-targeted delivery. A large number of research articles have been published reporting their fabrication methods and applications in pharmaceutical and cosmetic fields. Niosomes have the same advantages as liposomes, such as the ability to incorporate both hydrophilic and lipophilic compounds. Besides, niosomes can be fabricated with simple methods, require less production cost and are stable over an extended period, thus overcoming the major drawbacks of liposomes. This review provides a comprehensive summary of niosomal research to date, it provides a detailed overview of the formulation components, types of niosomes, effects of components on the formation of niosomes, fabrication and purification methods, physical characterization techniques of niosomes, recent applications in pharmaceutical field such as in oral, ocular, topical, pulmonary, parental and transmucosal drug delivery, and cosmetic applications. Finally, limitations and the future outlook for this delivery system have also been discussed.

Ascorbic acid derivative-loaded modified aspasomes: formulation, in vitro, ex vivo and clinical evaluation for melasma treatment

Vitamin C (L-Ascorbic acid) has many favourable effects on the skin such as antioxidant, anti-aging and whitening effects. Its instability and low permeability limit its pharmaceutical use in cosmetic and dermatological products. Instead, Mg ascorbyl phosphate (MAP), an ascorbic acid derivative, has the same effect with higher stability is being used. In this work, a vesicular system, aspasomes, containing MAP was developed and evaluated. Aspasomes are multilayered vesicles formed by amphiphiles molecules, Ascorbyl palmitate (ASP), in combination with cholesterol and charged lipids for drug encapsulation. Here, we investigated the use of lecithin instead of the charged lipid dicetyl phosphate for aspasomes development. Nine formulations were prepared and evaluated for their entrapment efficiency, particle size, polydispersity index (PDI) and zeta potential. Their entrapment efficiency ranged from 33.00 ± 2.27 to 95.18 ± 1.06, while their particle size was from 373.34 ± 60.85 to 464.37 ± 93.46 nm with acceptable PDI (from 0.212 ± 0.068 to 0.351 ± 0.061) and zeta potential (from -37.52 ± 2.42 to -50.36 ± 1.82). Three formulations were selected and evaluated for their drug release, permeation and retention into skin. One formulation was selected to be formulated as aspasomal topical cream and gel. The aspasomal cream was found to have enhanced drug permeation and skin retention over the aspasomal gel as well as the aspasomes formulation. MAP aspasomal cream was evaluated clinically as an effective treatment for melasma against 15% trichloroacetic acid (TCA) and the results recorded that the aspasomal cream showed the greatest degree of improvement regarding the hemi-MASI scores with 35% of patients rating it as excellent treatment. The study showed that MAP aspasomal cream can be considered a novel treatment of melasma which is free of side effects. Its efficacy as a monotherapy is superior to that of chemical peeling using 15% TCA.

Oxidative stability of flaxseed oil: Effect of hydrophilic, hydrophobic and intermediate polarity antioxidants

Oxidative deterioration is a major issue limiting the utilization of flaxseed oil (FSO). Present study explored the effects of hydrophilic (tannic acid), hydrophobic (alpha-tocopherol), and intermediate polarity (ascorbyl palmitate) natural antioxidants, which displayed highest DPPH radical scavenging and iron chelating abilities among several others, on the oxidative stability of FSO. A synthetic antioxidant (TBHQ) was also used as a control. FSO oxidation was examined by peroxide and p-anisidine values during 30-day storage at 25, 40 and 60 °C, and by accelerated oxidation using a rancimat at 110 °C. On mass concentration basis, all natural antioxidants were less effective than TBHQ. Irrespective of the polarity, all natural antioxidants, except alpha tocopherol, delayed primary and secondary oxidation, and increased the oxidative stability index. The alpha-tocopherol displayed pro-oxidant effect at all concentrations. Rather than polarity, antioxidant capacities, and their ability to replace minor components from the oil-water interface were crucial for the protection of FSO.

Methotrexate Aspasomes Against Rheumatoid Arthritis: Optimized Hydrogel Loaded Liposomal Formulation with In Vivo Evaluation in Wistar Rats

Aspasomes of methotrexate with antioxidant, ascorbyl palmitate, were developed and optimized using factorial design by varying parameters such as lipid molar ratio, drug to lipid molar ratio, and type of hydration buffer for transdermal delivery for disease modifying activity in rheumatoid arthritis (RA). Aspasomes were characterized by drug-excipients interaction, particle size analysis, determination of zeta potential, entrapment efficiency, and surface properties. The best formulation was loaded into hydrogel for evaluation of in vitro drug release and tested in vivo against adjuvant induced arthritis model in wistar rats, by assessing various physiological, biochemical, hematological, and histopathological parameters. Optimized aspasome formulation exhibited smooth surface with particle size 386.8 nm, high drug loading (19.41%), negative surface potential, and controlled drug release in vitro over 24 h with a steady permeation rate. Transdermal application of methotrexate-loaded aspasome hydrogel for 12 days reduced rat paw diameter (21.25%), SGOT (40.43%), SGPT (54.75%), TNFα (33.99%), IL β (34.79%), cartilage damage (84.41%), inflammation (82.37%), panus formation (84.38%), and bone resorption (80.52%) as compared to arthritic control rats. Free methotrexate-treated group showed intermediate effects. However, drug-free aspasome treatment did not show any effect. The experimental results indicate a positive outcome in development of drug-loaded therapeutically active carrier system which presents a non-invasive controlled release transdermal formulation with good drug loading, drug permeation rate, and having better disease modifications against RA than the free drug, thereby providing a more attractive therapeutic strategy for rheumatoid disease management.

Tumor regression and modulation of gene expression via tumor-targeted tocotrienol niosomes

AIM

To develop 6-O-palmitoyl-ascorbic acid-based niosomes targeted to transferrin receptor for intravenous administration of tocotrienols (T3) in breast cancer.

MATERIALS & METHODS

Niosomes were prepared using film hydration and ultrasonication methods. Transferrin was coupled to the surface of niosomes via chemical linker. Nanovesicles were characterized for size, zeta potential, morphology, stability and biological efficacy.

RESULTS

When evaluated in MDA-MB-231 cells, entrapment of T3 in niosomes caused 1.5-fold reduction in IC₅₀ value compared with nonformulated T3. In vivo, the average tumor volume of mice treated with tumor-targeted niosomes was 12-fold lower than that of untreated group, accompanied by marked downregulation of three genes involved in metastasis.

CONCLUSION

Findings suggested that tumor-targeted niosomes served as promising delivery system for T3 in cancer therapy.

Ascorbyl palmitate/d-α-tocopheryl polyethylene glycol 1000 succinate monoester mixed micelles for prolonged circulation and targeted delivery of compound K for antilung cancer therapy in vitro and in vivo

The roles of ginsenoside compound K (CK) in inhibiting tumor have been widely recognized in recent years. However, low water solubility and significant P-gp efflux have restricted its application. In this study, CK ascorbyl palmitate (AP)/d-α-tocopheryl polyethylene glycol 1000 succinate monoester (TPGS) mixed micelles were prepared as a delivery system to increase the absorption and targeted antitumor effect of CK. Consequently, the solubility of CK increased from 35.2±4.3 to 1,463.2±153.3 μg/mL. Furthermore, in an in vitro A549 cell model, CK AP/TPGS mixed micelles significantly inhibited cell growth, induced G0/G1 phase cell cycle arrest, induced cell apoptosis, and inhibited cell migration compared to free CK, all indicating that the developed micellar delivery system could increase the antitumor effect of CK in vitro. Both in vitro cellular fluorescence uptake and in vivo near-infrared imaging studies indicated that AP/TPGS mixed micelles can promote cellular uptake and enhance tumor targeting. Moreover, studies in the A549 lung cancer xenograft mouse model showed that CK AP/TPGS mixed micelles are an efficient tumor-targeted drug delivery system with an effective antitumor effect. Western blot analysis further confirmed that the marked antitumor effect in vivo could likely be due to apoptosis promotion and P-gp efflux inhibition. Therefore, these findings suggest that the AP/TPGS mixed micellar delivery system could be an efficient delivery strategy for enhanced tumor targeting and antitumor effects.

Non-Ionic Surfactant Vesicles (Niosomes) as New Drug Delivery Systems

Lipid vesicular systems composed of hydrated amphihiles with or without bilayer inducing agents such as cholesterol. On the basis of used amphiphilic molecule different nomenclature are used as liposomes, ufasomes and niosomes. Nonionic surfactants with mono-, di- or trialkyl chains form niosomes which are lipid vesicles with more chemical stability in comparison with phospholipids of liposomes. Both hydrophobic and hydrophilic chemicals can be encapsulated in niosomes as a new drug delivery system. This drug carrier system could have administered via injection, oral, pulmonary, vaginal, rectal, ophthalmic, nasal or transdermal routes with penetration enhancing potential. This chapter presents a detailed explain about niosome forming components, methods of preparation and routes of administration. Many examples for drug delivery potential of niosomes are also available in this review. Vaccine adjuvant and genetic substances vector capabilities are not given here.

Non-Ionic Surfactant Vesicles (Niosomes) as New Drug Delivery Systems

Lipid vesicular systems composed of hydrated amphihiles with or without bilayer inducing agents such as cholesterol. On the basis of used amphiphilic molecule different nomenclature are used as liposomes, ufasomes and niosomes. Nonionic surfactants with mono-, di- or trialkyl chains form niosomes which are lipid vesicles with more chemical stability in comparison with phospholipids of liposomes. Both hydrophobic and hydrophilic chemicals can be encapsulated in niosomes as a new drug delivery system. This drug carrier system could have administered via injection, oral, pulmonary, vaginal, rectal, ophthalmic, nasal or transdermal routes with penetration enhancing potential. This chapter presents a detailed explain about niosome forming components, methods of preparation and routes of administration. Many examples for drug delivery potential of niosomes are also available in this review. Vaccine adjuvant and genetic substances vector capabilities are not given here.

Co-delivery of docetaxel and palmitoyl ascorbate by liposome for enhanced synergistic antitumor efficacy

Palmitoyl ascorbate (PA) as an antioxidant has the potential for the treatment of cancer. In the present study, a nanocarrier system was developed for co-delivery of docetaxel (DOC) with palmitoyl ascorbate and the therapeutic efficacy of a combination drug regimen was investigated. For this purpose, different ratios of docetaxel and palmitoyl ascorbate were co-encapsulated in a liposome and they all showed high encapsulation efficiency. The average diameters of the liposomes ranged from 140 to 170 nm. Negative zeta potential values were observed for all systems, ranged from -40 mV to -56 mV. Studies on drug release and cellular uptake of the co-delivery system demonstrated that both drugs were effectively taken up by the cells and released slowly. Moreover, the liposome loading drugs with DOC/PA concentration ratio of 1:200 showed the highest anti-tumor activity to three different types of tumor cells. The higher in vivo therapeutic efficacy with lower systemic toxicity of the DOC-PA₂₀₀-LPs was also verified by the H22 tumor bearing mice model. Our results showed that such co-loaded delivery systems could serve as a promising therapeutic approach to improve clinical outcomes against hepatic carcinoma.

Liquid crystalline phase behavior of silica nanorods in dimethyl sulfoxide and water

We report lyotropic smectic liquid crystalline phase behavior of silica nanorods dispersed in binary mixtures of dimethyl sulfoxide (DMSO) and water (H2O). The phase behavior is affected by nanorod size polydispersity and DMSO concentration in the binary solvent. The isotropic to biphasic transition is strongly affected by the relative amount of DMSO in the solvent, but the solvent has little effect on the biphasic to liquid crystal transition above 40/60 DMSO/H2O by volume. At less than 40% DMSO, increasing silica nanorod concentration initially results in the formation of liquid crystalline domains, but further increasing silica concentration results in crystal solvate formation. The morphology of the liquid crystalline phase is strongly affected by the size polydispersity, with lower polydispersity leading to a more uniform structure. As in other lyotropic nanocylinder systems, the microstructure of continuous solid films produced from the dispersions was affected by both the initial microstructure and the applied shear.

Ascorbyl palmitate/DSPE-PEG nanocarriers for oral iron delivery: preparation, characterisation and in vitro evaluation

The objective of this study was to encapsulate iron in nanocarriers formulated with ascorbyl palmitate and 1,2-distearoyl-sn-glycero-3-phosphoethanolamine polyethylene glycol (DSPE-PEG) for oral delivery. Blank and iron (Fe) loaded nanocarriers were prepared by a modified thin film method using ascorbyl palmitate and DSPE-PEG. Surface charge of the nanocarriers was modified by the inclusion of chitosan (CHI) during the formulation process. Blank and iron loaded ascorbyl palmitate/DSPE nanocarriers were visualised by transmission electron microscopy (TEM) and physiochemical characterisations of the nanocarriers carried out to determine the mean particle size and zeta potential. Inclusion of chitosan imparted a net positive charge on the nanocarrier surface and also led to an increase in mean particle size. Iron entrapment in ascorbyl palmitate-Fe and ascorbyl palmitate-CHI-Fe nanocarriers was 67% and 76% respectively, suggesting a beneficial effect of chitosan on nanocarrier Fe entrapment. Iron absorption was estimated by measuring Caco-2 cell ferritin formation using ferrous sulphate as a reference standard. Iron absorption from ascorbyl palmitate-Fe (592.17±21.12 ng/mg cell protein) and ascorbyl palmitate-CHI-Fe (800.12±47.6 ng/mg, cell protein) nanocarriers was 1.35-fold and 1.5-fold higher than that from free ferrous sulphate, respectively (505.74±23.73 ng/mg cell protein) (n=6, p<0.05). This study demonstrates for the first time preparation and characterisation of iron loaded ascorbyl palmitate/DSPE PEG nanocarriers, and that engineering of the nanocarriers with chitosan leads to a significant augmentation of iron absorption.

Nanocarrier with self-antioxidative property for stabilizing and delivering ascorbyl palmitate into skin

The concept of a nanocarrier with a self-antioxidative property to deliver and stabilize a labile drug while at the same time providing a free radical scavenging activity is demonstrated. Curcumin was grafted onto a poly(vinyl alcohol) [PV(OH)] chain, and the nanocarriers fabricated from the obtained curcumin-grafted PV(OH) polymer [CUR-PV(OH)] showed a good free radical scavenging activity. Ascorbyl palmitate (AP) could be effectively loaded into the CUR-PV(OH) at 29% by weight. The CUR-PV(OH)-encapsulated AP was 77% more stable than the free (unencapsulated) AP, and 47% more stable than AP encapsulated in the control nanocarrier with no antioxidative property [cinnamoyl-grafted PV(OH); CIN-PV(OH)]. Although coencapsulation of curcumin and AP into CIN-PV(OH) showed some improvement on the AP stability, AP was more stable when encapsulated in CUR-PV(OH). Compared with the free AP, encapsulated AP within the CUR-PV(OH) nanocarriers showed not only a better penetration into pig skin dermis via hair follicle pathway followed by the release and diffusion of the AP, but also a greater AP stability after skin application. Although a proof of principle is shown for CUR-PV(OH) and AP, it is likely that other carriers of the same principal could be designed and applied to different oxidation-sensitive drugs.

Lipoidal soft hybrid biocarriers of supramolecular construction for drug delivery

Lipid-based innovations have achieved new heights during the last few years as an essential component of drug development. The current challenge of drug delivery is liberation of drug agents at the right time in a safe and reproducible manner to a specific target site. A number of novel drug delivery systems has emerged encompassing various routes of administration, to achieve controlled and targeted drug delivery. Microparticulate lipoidal vesicular system represents a unique technology platform suitable for the oral and systemic administration of a wide variety of molecules with important therapeutic biological activities, including drugs, genes, and vaccine antigens. The success of liposomes as drug carriers has been reflected in a number of liposome-based formulations, which are commercially available or are currently undergoing clinical trials. Also, novel lipid carrier-mediated vesicular systems are originated. This paper has focused on the lipid-based supramolecular vesicular carriers that are used in various drug delivery and drug targeting systems.

Lipoidal soft hybrid biocarriers of supramolecular construction for drug delivery

Lipid-based innovations have achieved new heights during the last few years as an essential component of drug development. The current challenge of drug delivery is liberation of drug agents at the right time in a safe and reproducible manner to a specific target site. A number of novel drug delivery systems has emerged encompassing various routes of administration, to achieve controlled and targeted drug delivery. Microparticulate lipoidal vesicular system represents a unique technology platform suitable for the oral and systemic administration of a wide variety of molecules with important therapeutic biological activities, including drugs, genes, and vaccine antigens. The success of liposomes as drug carriers has been reflected in a number of liposome-based formulations, which are commercially available or are currently undergoing clinical trials. Also, novel lipid carrier-mediated vesicular systems are originated. This paper has focused on the lipid-based supramolecular vesicular carriers that are used in various drug delivery and drug targeting systems.

Formulation, evaluation, and pharmacokinetics of isradipine proliposomes for oral delivery

Proliposomes loaded with isradipine were prepared successfully to enhance the oral bioavailability of isradipine. In this study, proliposomes were prepared by film deposition by the carrier method with varying ratios of hydrogenated soy phosphatidyl choline (HSPC) and cholesterol using spray-dried mannitol (Pearlitol SD 200) as the carrier. The formulation containing an equimolar ratio of HSPC and cholesterol showed smaller vesicle size, high surface charge, and entrapment efficiency. The formation of liposomes and surface morphology of optimized proliposome formulation was studied by optical and scanning electron microscopy, respectively. Fourier transform infrared, differential scanning calorimetry, and powder X-ray diffractometry studies were performed to assess the solid-state characteristics of the formulation. Ex vivo permeation enhancement assessed from flux, permeability coefficient, and enhancement ratio were significantly higher for proliposomes, compared to control. The pharmacokinetic parameters were evaluated in male albino Wistar rats, and a significant improvement in bioavailability (2.4-fold) was observed from the optimized proliposome formulation, compared to control (oral suspension). The stability study revealed that the formulations are stable when stored at 4°C.