Effect of Formulation and Processing Variables on Dexamethasone Entrapment and Release of Niosomes

Desosomes and desimicelles - a novel vesicular and micellar system for enhanced oral delivery of poorly soluble drug: Optimization of in vitro characteristics and in vivo performance

This study introduces two innovative nanocarrier systems to improve oral drug delivery. Desosomes and desimicelles combine Deep eutectic solvent (DES) with vesicular or micellar nanosystems, respectively. These novel nanosystems integrate the DES solubilization potency for administering drugs with low aqueous solubility and the vesicular and micellar systems to bypass physiological barriers and improve poor drug bioavailability. Lornoxicam (LRX) is a BCS class II anti-inflammatory with limited aqueous solubility and rapid clearance. Desosomes and desimicelles were prepared and successfully optimized. The optimization depended on particle size, zetapotential, entrapment efficiency, and solubility. The optimized desosomes (LRX-DES-V) and desimicelles (LRX-DES-M) were pictured by transmission electron microscope. Differential scanning calorimetry (DSC) and FTIR analysis indicated the successful inclusion of LRX inside each system. Invitro LRX release profiles revealed controlled release of LRX-DES-V and LRX-DES-M, with more sustained release by the later one. In-vivo study, inflammation was induced using a carrageenan rat model, and the anti-inflammatory effect of LRX-pure, marketed product, traditional niosomes, LRX-DES-V & LRX-DES-M were determined using inhibition %, serum inflammatory cytokines, and histopathology. After 4 h of induction, LRX-DES-M (68.05%) showed a significant inhibition compared to LRX-DES-V (63.57%). LRX-DES-M also showed a better reduction in COX2, PGE2, and TNF-α (1.25-fold, 1.24-fold, and 1.36-fold inhibition), respectively, compared to LRX-DES-V. We can conclude that LRX-DES-V and LRX-DES-M showed better effects than all other groups and that LRX-DES-M might be more effective than LRX-DES-V.

Development of brimonidine niosomes laden contact lenses for extended release and promising delivery system in glaucoma treatment

BACKGROUND

Increased intraocular pressure is a common symptom of glaucoma. In severe circumstances, it may result in loss of eyesight. Glaucoma treatment is difficult due to ocular physiological barriers that prevent medications from reaching the afflicted area. Traditional formulations (eye drops) have a short residence period and are rapidly drained away via the nasolacrimal duct, resulting in increased adverse drug responses and lower efficacy. The usage of nanoparticles such as niosomes could be one potential answer to these problems. While niosomes improve drug penetration, they have little effect on ocular retention of the medication. Contact lenses containing niosomes can assist to overcome this disadvantage.

OBJECTIVE

This study aims to prepare and evaluate Brimonidine niosomes laden contact lenses for the treatment of Glaucoma.

METHODS

Brimonidine niosomes were prepared using thin film hydration method and evaluated. The contact lenses were soaked in the niosomal formulation at varying intervals (3-10 days). Thereafter, the contact lenses were evaluated for %transmittance, %swelling index, drug quantification and in vitro drug release. The pharmacodynamic studies were conducted to assess the reduction in intraocular pressure (IOP) in albino rabbits. The research compared the results of the reduction in intraocular pressure caused by Brimonidine niosomes laden contact lenses with a marketed preparation of niosomes.

RESULTS

Higher concentration of the drug was loaded in contact lenses loaded with Brimonidine niosomes compared to the marketed formulation, by soaking method. The contact lenses exhibited an optimal %transmittance of 98.02 ± 0.36 and %swelling index of 50.35 ± 0.57. Increase in the soaking time up to 7 days led to an increase in the drug concentration in the contact lenses. However, no further increase was observed after the 7th day due to saturation of the contact lenses. Brimonidine niosomes laden contact lenses provided a reduction in intraocular pressure that was similar to the marketed preparation. Further, the contact lenses provided extended release up to 20 h.

CONCLUSION

Brimonidine niosomes laden contact lenses exhibited superior drug loading through the soaking method, displaying optimal %transmittance and %swelling index. Soaking for 7 days increased drug concentration in contact lenses with no further increase due to saturation. These lenses reduced intraocular pressure like the marketed formulation, offering extended release for 20 h.

Reassembly of the vesicular structure of niosomes after their destruction in a mechanical field

This paper presents, for the first time, evidence for vesicle destruction and payload loss at the stage of purification of niosome dispersions by centrifugation, an important operation in the assembly of vesicular materials. The ability of niosomes of different compositions to reassemble, i.e., to restore the vesicular structure after destruction in the field of centrifugal forces, was demonstrated by dynamic light scattering and fluorescence spectroscopy. The kinetics of reassembly of vesicular structures is determined by the strength of the centrifugal field and the composition of niosomes. In contrast to ternary compositions, where particle size and modality are essentially unchanged after redispersion of the precipitate resulting from centrifugation, niosome dispersions containing anionic dicetyl phosphate includes micron-sized particles after redispersion, which vary in size over a wide range throughout the observation period. The reassembly process is complicated by the presence of charge on the surface of the niosomes. Elastic niosomes - ethosomes have been synthesised which, due to the high deformability of the shells, are less susceptible to destruction in the centrifugal field and retain the contents of the aqueous core. Using the "energy landscape" approximation, it is shown that vesicular structures assembled during hydration and reassembled after their centrifugation occupy different positions in the energetic pathway of their preparation. The results obtained should also be taken into account when determining the entrapment efficiency, since this procedure uses centrifugation to separate the load. It is important to note that the physical stability of niosomes, which is usually considered in terms of the functional activity of particles, is manifest and should be considered at the material preparation stage.

Composition, preparation methods, and applications of nanoniosomes as codelivery systems: a review of emerging therapies with emphasis on cancer

Nanoniosome-based drug codelivery systems have become popular therapeutic instruments, demonstrating tremendous promise in cancer therapy, infection treatment, and other therapeutic domains. An emerging form of vesicular nanocarriers, niosomes are self-assembling vesicles composed of nonionic surfactants, along with cholesterol or other amphiphilic molecules. This comprehensive review focuses on how nanosystems may aid in making anticancer and antibacterial pharmaceuticals more stable and soluble. As malleable nanodelivery instruments, the composition, types, preparation procedures, and variables affecting the structure and stability of niosomes are extensively investigated. In addition, the advantages of dual niosomes for combination therapy and the administration of multiple medications simultaneously are highlighted. Along with categorizing niosomal drug delivery systems, a comprehensive analysis of various preparation techniques, including thin-layer injection, ether injection, and microfluidization, is provided. Dual niosomes for cancer treatment are discussed in detail regarding the codelivery of two medications and the codelivery of a drug with organic, plant-based bioactive compounds or gene agents. In addition, niogelosomes and metallic niosomal carriers for targeted distribution are discussed. The review also investigates the simultaneous delivery of bioactive substances and gene agents, including siRNA, microRNA, shRNA, lncRNA, and DNA. Additional sections discuss the use of dual niosomes for cutaneous drug delivery and treating leishmanial infections, Pseudomonas aeruginosa, and Mycobacterium tuberculosis. The study concludes by delineating the challenges and potential routes for nanoniosome-based pharmaceutical codelivery systems, which will be useful for nanomedicine practitioners and researchers.

Formulation and Characterization of Curcumin Niosomes: Antioxidant and Cytotoxicity Studies

Curcumin's applications in the treatment of conditions including osteoarthritis, dementia, malignancies of the pancreas, and malignancies of the intestines have drawn increasing attention. It has several wonderful qualities, including being an anti-inflammatory agent, an anti-mutagenic agent, and an antioxidant, and has substantially reduced inherent cytotoxicity outcomes. Although curcumin possesses multiple known curative properties, due to its limited bioavailability, it is necessary to develop efficient strategies to overcome these hurdles. To establish an effective administration method, various niosomal formulations were optimized using the Box-Behnken design and assessed in the current investigation. To examine the curcumin niosomes, zeta sizer, zeta potential, entrapment efficiency, SEM, antioxidant potential, cytotoxicity, and release studies were performed. The optimized curcumin niosomes exhibited an average particle size of 169.4 nm, a low PDI of 0.189, and high entrapment efficiency of 85.4%. The release profile showed 79.39% curcumin after 24 h and had significantly higher antioxidant potential as compared with that of free curcumin. The cytotoxicity results of curcumin niosomes presented increased mortality in human ovarian cancer A2780.

Dexamethasone: Insights into Pharmacological Aspects, Therapeutic Mechanisms, and Delivery Systems

Dexamethasone (DEX) has been widely used to treat a variety of diseases, including autoimmune diseases, allergies, ocular disorders, cancer, and, more recently, COVID-19. However, DEX usage is often restricted in the clinic due to its poor water solubility. When administered through a systemic route, it can elicit severe side effects, such as hypertension, peptic ulcers, hyperglycemia, and hydro-electrolytic disorders. There is currently much interest in developing efficient DEX-loaded nanoformulations that ameliorate adverse disease effects inhibiting advancements in scientific research. Various nanoparticles have been developed to selectively deliver drugs without destroying healthy cells or organs in recent years. In the present review, we have summarized some of the most attractive applications of DEX-loaded delivery systems, including liposomes, polymers, hydrogels, nanofibers, silica, calcium phosphate, and hydroxyapatite. This review provides our readers with a broad spectrum of nanomedicine approaches to deliver DEX safely.

Formulation, Optimization and Evaluation of Luteolin-Loaded Topical Nanoparticulate Delivery System for the Skin Cancer

In the present study, luteolin (LT)-loaded nanosized vesicles (LT-NVs) were prepared by a solvent evaporation-hydration method using phospholipid and edge activator. The formulation was optimized using three factors at a three-level Box-Behnken design. The formulated LT-NVs were prepared using the three independent variables phospholipid (A), edge activator (B) and sonication time (C). The effect of used variables was assessed on the vesicle size (Y1) and encapsulation efficiency (Y2). The selection of optimum composition (LT-NVopt) was based on the point prediction method of the software. The prepared LT-NVopt showed the particle size of 189.92 ± 3.25 nm with an encapsulation efficiency of 92.43 ± 4.12% with PDI and zeta potential value of 0.32 and -21 mV, respectively. The formulation LT-NVopt was further converted into Carbopol 934 gel (1% w/v) to enhance skin retention. LT-NVoptG was further characterized for viscosity, spreadability, drug content, drug release, drug permeation and antioxidant, antimicrobial and cytotoxicity assessment. The evaluation result revealed optimum pH, viscosity, spreadability and good drug content. There was enhanced LT release (60.81 ± 2.87%), as well as LT permeation (128.21 ± 3.56 µg/cm2/h), which was found in comparison to the pure LT. The antioxidant and antimicrobial study results revealed significantly (p ˂ 0.05) better antioxidant potential and antimicrobial activity against the tested organisms. Finally, the samples were evaluated for cytotoxicity assessment using skin cancer cell line and results revealed a significant difference in the viability % at the tested concentration. LT-NVoptG showed a significantly lower IC50 value than the pure LT. From the study, it can be concluded that the prepared LT-NVoptG was found to be an alternative to the synthetic drug as well as conventional delivery systems.

Evaluation of sonication on stability-indicating properties of optimized pilocarpine hydrochloride-loaded niosomes in ocular drug delivery

Niosomes are increasingly explored for enhancing drug penetration and retention in ocular tissues for both posterior and anterior eye delivery. They have been employed in encapsulating both hydrophilic and hydrophobic drugs, but their use is still plagued with challenges of stability and poor entrapment efficiency particularly with hydrophilic drugs. As a result, focus is on understanding the parameters that affect their stability and their optimization for improved results. Pilocarpine hydrochloride (HCl), a hydrophilic drug is used in the management of intraocular pressure in glaucoma. We aimed at optimizing pilocarpine HCl niosomes and evaluating the effect of sonication on its stability-indicating properties such as particle size, polydispersity index (PDI), zeta potential and entrapment efficiency. Pilocarpine niosomes were prepared by ether injection method. Composition concentrations were varied and the effects of these variations on niosomal properties were evaluated. The effects of sonication on niosomes were determined by sonicating optimized drug-loaded formulations for 30 min and 60 min. Tween 60 was confirmed to be more suitable over Span 60 for encapsulating hydrophilic drugs, resulting in the highest entrapment efficiency (EE) and better polydispersity and particle size indices. Optimum sonication duration as a process variable was determined to be 30 min which increased EE from 24.5% to 42% and zeta potential from (-)14.39 ± 8.55 mV to (-)18.92 ± 7.53 mV. In addition to selecting the appropriate surfactants and varying product composition concentrations, optimizing sonication parameters can be used to fine-tune niosomal properties to those most desirable for extended eye retainment and maintenance of long term stability.

Phytochemical delivery through nanocarriers: a review

In recent times, phytochemicals encapsulated or conjugated with nanocarriers for delivery to the specific sites have gained considerable research interest. Phytochemicals are mostly plant secondary metabolites which reported to be beneficial for human health and in disease theraphy. However, these compound are large size and polar nature of these compounds, make it difficult to cross the blood-brain barrier (BBB), endothelial lining of blood vessels, gastrointestinal tract and mucosa. Moreover, they are enzymatically degraded in the gastrointestinal tract. Therefore, encapsulation or conjugation of these compounds with nanocrriers could be an alternate way to enhance their bioefficacy by influencing their gastrointestinal stability, rate of absorption and dispersion. This review presents an overview of nanocarriers alternatives which improves therapeutic value and avoid toxicity, by releasing bioactive compounds specifically at target tissues with enhanced stability and bioavailability. Future investigations may emphasize on deciphering the structural changes in nanocarriers during digestion and absorption, the difference between in-vitro and in-vivo digestion simulations, and impact of nanocarriers on the metabolism of phytochemicals.

Buspirone Hydrochloride Loaded In Situ Nanovesicular Gel as an Anxiolytic Nasal Drug Delivery System: In Vitro and Animal Studies

Nasal nanovesicular gels of buspirone hydrochloride (BH) were prepared and characterized aiming for sustained delivery and enhancing bioavailability. Buspirone hydrochloride has low bioavailability of about 4% after oral administration due to first pass metabolism. Buspirone hydrochloride nanovesicles were formulated by thin film hydration method (TFH). The selected nanovesicular formulation was incorporated into two types of in situ gels (pH-induced and thermoreversible) using carbopol 974P and poloxamer 407 (P407), respectively, together with different mucoadhesive polymers. The in situ gels were examined for pH, gelling capability, viscosity, content uniformity, mucoadhesiveness, and in vitro drug release. The ex vivo permeation performance of the in situ gel formulations that showed the most sustained release was also assessed. The in vivo study was done by the determination of BH blood level in albino rabbits after nasal administration. Results revealed that nanovesicles prepared using Span 60 and cholesterol in a ratio of 80:20 showed the highest EE% (70.57 ± 1.00%). The ex vivo permeation data confirmed higher permeability figures for carbopol formulation in comparison to poloxamer formulations. The in vivo study data showed an increase of 3.26 times in BH bioavailability when formulated into the carbopol nanovesicular in situ gel relative to control (nasal drug solution).

Advances of Non-Ionic Surfactant Vesicles (Niosomes) and Their Application in Drug Delivery

Non-Ionic surfactant based vesicles, also known as niosomes, have attracted much attention in pharmaceutical fields due to their excellent behavior in encapsulating both hydrophilic and hydrophobic agents. In recent years, it has been discovered that these vesicles can improve the bioavailability of drugs, and may function as a new strategy for delivering several typical of therapeutic agents, such as chemical drugs, protein drugs and gene materials with low toxicity and desired targeting efficiency. Compared with liposomes, niosomes are much more stable during the formulation process and storage. The required pharmacokinetic properties can be achieved by optimizing components or by surface modification. This novel delivery system is also easy to prepare and scale up with low production costs. In this paper, we summarize the structure, components, formulation methods, quality control of niosome and its applications in chemical drugs, protein drugs and gene delivery.