Mucoadhesive niosomal in situ gel for ocular tissue targeting: in vitro and in vivo evaluation of lomefloxacin hydrochloride

Oleogels for the ocular delivery of epalrestat: formulation, in vitro, in ovo, ex vivo and in vivo evaluation

The ocular administration of lipophilic and labile drugs such as epalrestat, an aldose reductase inhibitor with potential for diabetic retinopathy treatment, demands the development of topical delivery systems capable of providing sufficient ocular bioavailability. The aim of this work was to develop non-aqueous oleogels based on soybean oil and gelators from natural and sustainable sources (ethyl cellulose, beeswax and cocoa butter) and to assess their reproducibility, safety and efficiency in epalrestat release and permeation both ex vivo and in vivo. Binary combinations of gelators at 10% w/w resulted in solid oleogels (oleorods), while single gelator oleogels at 5% w/w remained liquid at room temperature, with most of the oleogels displaying shear thinning behavior. The oleorods released up to 4 µg epalrestat per mg of oleorod in a sustained or burst pattern depending on the gelator (approx. 10% dose in 24 h). The HET-CAM assay indicated that oleogel formulations did not induce ocular irritation and were safe for topical ocular administration. Corneal and scleral ex vivo assays evidenced the permeation of epalrestat from the oleorods up to 4 and 2.5 µg/cm2 after six hours, respectively. Finally, the capacity of the developed oleogels to sustain release and provide significant amounts of epalrestat to the ocular tissues was demonstrated in vivo against aqueous-based niosomes and micelles formulations loaded with the same drug concentration. Overall, the gathered information provides valuable insights into the development of oleogels for ocular drug delivery, emphasizing their safety and controlled release capabilities, which have implications for the treatment of diabetic neuropathy and other ocular conditions.

Phospholipid Free Nano-Vesicles of Brinzolamide Biopolymer Ocular Insert; Design, In vitro and In vivo Evaluation

The aim of this work to study the feasibility of using phospholipid free vesicles with positive charge inducer in a slowly dissolving polymer ocular insert to successfully control intraocular pressure (IOP) for an extended period. Brinzolamide (BRNZ) was chosen as a model drug and a full factorial design was assembled to investigate the drug loading effect, ratio of cholesterol to fatty moiety and the type of the fatty moiety used on the vesicle size and entrapment efficiency. Linear regression models were constructed, and optimization of the formulation compositions yielded two formulae with palmitic acid as a negatively charged vesicles and cetrimide positively charged vesicles. Both formulae were studied in term of permeation efficiency through bovine corneal membranes. Positively charged vesicles although it didn't achieve the highest flux and cumulative amount permeated per unit surface area in the experiment time course, it achieved the highest retention of drug inside the corneal tissue, so it was chosen to be incorporated in a slowly dissolving polymer ocular insert. The insert was evaluated in term content, physical evaluation, and release properties. In vivo evaluation of the casted ocular inserts was conducted in male albino rabbits against market eye drop product and IOP readings were collected for 48 hours. The positively charged sterosomes containing BRNZ and formulated in polymer ocular inserts achieved extended control of IOP of the test animals compared to the market product.

Fostering the unleashing potential of nanocarriers-mediated delivery of ocular therapeutics

Ocular delivery is the most challenging aspect in the field of pharmaceutical research. The major hurdle for the controlled delivery of drugs to the eye includes the physiological static barriers such as the complex layers of the cornea, sclera and retina which restrict the drug from permeating into the anterior and posterior segments of the eye. Recent years have witnessed inventions in the field of conventional and nanocarrier drug delivery which have shown considerable enhancement in delivering small to large molecules across the eye. The dynamic challenges associated with conventional systems include limited drug contact time and inadequate ocular bioavailability resulting from solution drainage, tear turnover, and dilution or lacrimation. To this end, various bioactive-based nanosized carriers including liposomes, ethosomes, niosomes, dendrimer, nanogel, nanofibers, contact lenses, nanoprobes, selenium nanobells, nanosponge, polymeric micelles, silver nanoparticles, and gold nanoparticles among others have been developed to circumvent the limitations associated with the conventional dosage forms. These nanocarriers have been shown to achieve enhanced drug permeation or retention and prolong drug release in the ocular tissue due to their better tissue adherence. The surface charge and the size of nanocarriers (10-1000 nm) are the important key factors to overcome ocular barriers. Various nanocarriers have been shown to deliver active therapeutic molecules including timolol maleate, ampicillin, natamycin, voriconazole, cyclosporine A, dexamethasone, moxifloxacin, and fluconazole among others for the treatment of anterior and posterior eye diseases. Taken together, in a nutshell, this extensive review provides a comprehensive perspective on the numerous facets of ocular drug delivery with a special focus on bioactive nanocarrier-based approaches, including the difficulties and constraints involved in the fabrication of nanocarriers. This also provides the detailed invention, applications, biodistribution and safety-toxicity of nanocarriers-based therapeutcis for the ophthalmic delivery.

Nanosuspensions in ophthalmology: Overcoming challenges and enhancing drug delivery for eye diseases

This review article provides a comprehensive overview of the advancements in using nanosuspensions for controlled drug delivery in ophthalmology. It highlights the significance of ophthalmic drug delivery due to the prevalence of eye diseases and delves into various aspects of this field. The article explores molecular mechanisms, drugs used, and physiological factors affecting drug absorption. It also addresses challenges in treating both anterior and posterior eye segments and investigates the role of mucus in obstructing micro- and nanosuspensions. Nanosuspensions are presented as a promising approach to enhance drug solubility and absorption, covering formulation, stability, properties, and functionalization. The review discusses the pros and cons of using nanosuspensions for ocular drug delivery and covers their structure, preparation, characterization, and applications. Several graphical representations illustrate their role in treating various eye conditions. Specific drug categories like anti-inflammatory drugs, antihistamines, glucocorticoids, and more are discussed in detail, with relevant studies. The article also addresses current challenges and future directions, emphasizing the need for improved nanosuspension stability and exploring potential technologies. Nanosuspensions have shown substantial potential in advancing ophthalmic drug delivery by enhancing solubility and absorption. This article is a valuable resource for researchers, clinicians, and pharmaceutical professionals in this field, offering insights into recent developments, challenges, and future prospects in nanosuspension use for ocular drug delivery.

Prolonged Release Niosomes For Ocular Delivery of Loteprednol: Ocular Distribution Assessment on Dry Eye Disease Induced Rabbit Model

Loteprednol etabonate (LE) is a topical corticosteroid for the symptomatic management of ocular conditions, encompassing both allergic and infectious etiologies. Owing to the dynamic and static barriers of the eye, LE exhibits significantly low bioavailability, necessitating an increase in the frequency of drug administration. The objective of this study is to overcome the limitations by developing niosomal systems loaded with LE. Design of Experiments (DoE) approach was used for the development of optimal niosome formulation. The optimal formulation was characterized using DLS, FT-IR, and DSC analysis. In vitro and ex vivo release studies were performed to demonstrate drug release patterns. After that HET-CAM evaluation was conducted to determine safety profile. Then, in vivo studies were carried out to determine therapeutic activity of niosomes. Zeta potential (ZP), particle size, polydispersity index (PI), and encapsulation efficacy (EE) were -33.8 mV, 89.22 nm, 0.192, and 89.6%, respectively. Medicated niosomes had a broad distribution within rabbit eye tissues and was absorbed by the aqueous humor of the bovine eye for up to 6 h after treatment. Cumulative permeated drug in the bovine eye and rabbit eye were recorded 52.45% and 54.8%, respectively. No irritation or hemorrhagic situation was observed according to the results of HET-CAM study. Thus, novel LE-loaded niosomal formulations could be considered as a promising treatment option for the dry-eye-disease (DED) due to enhanced bioavailability and decreased side effects.

Development and biological evaluation of smart powder bandage for wound healing and dressing applications

Cutaneous wounds are one of the pressing concerns for healthcare systems globally. With large amounts of water, conventional hydrogels encounter obstacles in effectively delivering small molecules and peptides for wound healing. The surplus water content challenges the stability and sustained release of small molecules and peptides, diminishing their therapeutic efficacy. Our pioneering smart powder bandage, fabricated through freeze-drying, ensures a water content of <1 % during storage. Upon contact with wound exudate, it forms hydrogel layers, thereby optimizing the delivery of peptides. Tailored for thermosensitive peptides such as EGF, this strategy surmounts the limitations of conventional hydrogels, providing a robust platform for efficacious therapeutic delivery in wound healing applications. Developing multifunctional wound dressings with antibacterial, anti-inflammatory, hemostatic, and healing properties is essential to promote wound healing. Therefore, the current investigation reports the development of multifunctional EGF@Silnanom SPB with the above-mentioned properties to promote wound healing using silver nanomix (Silnanom) and bioactive epidermal growth factors (EGF) as active therapeutics. The characterization of smart powder bandage (SPB) revealed that Silnanom were homogeneously dispersed in the entangled polymer network. The multifunctional smart powder bandage exhibited high bacterial inhibition rates against Escherichia coli (E. coli) and Staphylococcus aureus (S. aureus), and rigorous hemocompatibility, cell compatibility, and in vivo studies also confirmed its biocompatibility. Furthermore, multifunctional EGF@Silnanom SPB effectively reduced pro-inflammatory markers, enhanced collagen deposition, promoted angiogenesis, and accelerated wound healing in a full-thickness mouse wound model through the sustained release of Silnanom and EGF. Additionally, the results of hemostasis analysis on the tail amputation mouse model confirmed the hemostasis properties of the EGF@Silnanom SPB. Overall, the multifunctional EGF@Silnanom SPB shows promising potential for skin wound repair, offering a potent and effective solution to the challenges posed by conventional wound dressings.

Fabrication, assessment, and optimization of alendronate sodium nanoemulsion-based injectable in-situ gel formulation for management of osteoporosis

Low bone mass, degeneration of bone tissue, and disruption of bone microarchitecture are all symptoms of the disease osteoporosis, which can decrease bone strength and increase the risk of fractures. The main objective of the current study was to use a phospholipid-based phase separation in-situ gel (PPSG) in combination with an alendronate sodium nanoemulsion (ALS-NE) to help prevent bone resorption in rats. The effect of factors such as concentrations of the ALS aqueous solution, surfactant Plurol Oleique CC 497, and Maisine CC oil on nanoemulsion characteristics such as stability index and globular size was investigated using an l-optimal coordinate exchange statistical design. Injectable PPSG with the best nanoemulsion formulation was tested for viscosity, gel strength, water absorption, and in-vitro ALS release. ALS retention in the rats' muscles was measured after 30 days. The droplet size and stability index of the optimal nanoemulsion were 90 ± 2.0 nm and 85 ± 1.9%, respectively. When mixed with water, the optimal ALS-NE-loaded PPSG became viscous and achieved 36 seconds of gel strength, which was adequate for an injectable in-situ formulation. In comparison with the ALS solution-loaded in-situ gel, the newly created optimal ALS-NE-loaded PPSG produced the sustained and regulated release of ALS; hence, a higher percentage of ALS remained in rats' muscles after 30 days. PPSG that has been loaded with an ALS-NE may therefore be a more auspicious, productive, and effective platform for osteoporosis treatment than conventional oral forms.

In silico design and mechanistic study of niosome-encapsulated curcumin against multidrug-resistant Staphylococcus aureus biofilms

Curcumin, an important natural component of turmeric, has been known for a long time for its antimicrobial properties. This study aimed to investigate the anti-biofilm action of the niosome-encapsulated curcumin and explore the involved anti-biofilm mechanism. In silico investigations of ADME-Tox (absorption, distribution, metabolism, excretion, and toxicity) were first performed to predict the suitability of curcumin for pharmaceutical application. Curcumin showed low toxicity but at the same time, low solubility and low stability, which, in turn, might reduce its antimicrobial activity. To overcome these intrinsic limitations, curcumin was encapsulated using a biocompatible niosome system, and an encapsulation efficiency of 97% was achieved. The synthesized curcumin-containing niosomes had a spherical morphology with an average diameter of 178 nm. The niosomal curcumin was capable of reducing multi-drug resistant (MDR) Staphylococcus aureus biofilm 2-4-fold compared with the free curcumin. The encapsulated curcumin also demonstrated no significant cytotoxicity on the human foreskin fibroblasts. To understand the interaction between curcumin and S. aureus biofilm, several biofilm-related genes were analyzed for their expression. N-acetylglucosaminyl transferase (IcaD), a protein involved in the production of polysaccharide intercellular adhesion and known to play a function in biofilm development, was found to be downregulated by niosomal curcumin and showed high binding affinity (-8.3 kcal/mol) with curcumin based on molecular docking analysis. Our study suggests that the niosome-encapsulated curcumin is a promising approach for the treatment of MDR S. aureus biofilm and can be extended to biofilms caused by other pathogens.

Fabrication and optimization of phospholipids-based phase separation in-situ gel loaded with BMP-2 nanosized emulsion for bone defect

Introduction: The health, development, and/or survival of a newborn can be impacted by congenital abnormalities such as cleft lip (CLP) and palate, one of alveolar bone defects that emerge thru pregnancy. Therefore, the primary purpose of this study is to use phospholipids-based phase separation in-situ gel (PPSG) in combination with bone morphogenetic protein-2 nanoemulsion (BMP-2-NE) to aid repairing alveolar bone defects. Methods: To investigate how formulation parameters, such as the concentrations of BMP-2 aqueous solution, LauroglycolTM FCC, and Labrafac PG oil, affect NE qualities including droplet size and stability index, an l-optimal co-ordinate exchange statistical design was opted. Injectable PPSG with the best NE formulation was tested for viscosity characteristics, gel strength, water absorption, and in-vitro BMP-2 release. In rabbits, the percentage of BMP-2 that was still in the maxilla after 14 days was assessed. Results: Collected results revealed that the droplet size and stability index of optimal NE were discovered to be 68 2.0 nm and 96 1.3%, respectively. When mixed with water, optimal BMP-2 NE loaded PPSG became viscous and reached a gel strength of 41 s, which is adequate for injectable in-situ gels. In comparison to BMP-2 solution loaded in-situ gel, the in-vivo studies indicated that the newly created BMP-2 NE loaded PPSG produced a sustained and controlled release of BMP-2 that continued for 336 h (14 days). Further, 8% of the BMP-2 was still entrapped and not completely dissolved after 14 days, thus, created formulation allowed a higher percentage of BMP-2 to remain in rabbits' maxilla for longer time. Conclusion: PPSG that has been loaded with BMP-2 NE may therefore be a promising, fruitful, and less painful paradigm for the noninvasive therapy of CLP with significant effect and extended release.

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.

Ocular Drug Delivery: a Comprehensive Review

The human eye is a sophisticated organ with distinctive anatomy and physiology that hinders the passage of drugs into targeted ophthalmic sites. Effective topical administration is an interest of scientists for many decades. Their difficult mission is to prolong drug residence time and guarantee an appropriate ocular permeation. Several ocular obstacles oppose effective drug delivery such as precorneal, corneal, and blood-corneal barriers. Routes for ocular delivery include topical, intravitreal, intraocular, juxtascleral, subconjunctival, intracameral, and retrobulbar. More than 95% of marketed products exists in liquid state. However, other products could be in semi-solid (ointments and gels), solid state (powder, insert and lens), or mixed (in situ gel). Nowadays, attractiveness to nanotechnology-based carries is resulted from their capabilities to entrap both hydrophilic and lipophilic drugs, enhance ocular permeability, sustain residence time, improve drug stability, and augment bioavailability. Different in vitro, ex vivo, and in vivo characterization approaches help to predict the outcomes of the constructed nanocarriers. This review aims to clarify anatomy of the eye, various ocular diseases, and obstacles to ocular delivery. Moreover, it studies the advantages and drawbacks of different ocular routes of administration and dosage forms. This review also discusses different nanostructured platforms and their characterization approaches. Strategies to enhance ocular bioavailability are also explained. Finally, recent advances in ocular delivery are described.

Formulation and Evaluation of Moxifloxacin Loaded Bilosomes In-Situ Gel: Optimization to Antibacterial Evaluation

In this study, moxifloxacin (MX)-loaded bilosome (BS) in situ gel was prepared to improve ocular residence time. MX-BSs were prepared using the thin-film hydration method. They were optimized using a Box−Behnken design (BBD) with bile salt (A, sodium deoxycholate), an edge activator (B, Cremophor EL), and a surfactant (C, Span 60) as process variables. Their effects were assessed based on hydrodynamic diameter (Y1), entrapment efficacy (Y2), and polydispersity index (Y3). The optimized formulation (MX-BSop) depicted a low hydrodynamic diameter (192 ± 4 nm) and high entrapment efficiency (76 ± 1%). Further, MX-BSop was successfully transformed into an in situ gel using chitosan and sodium alginate as carriers. The optimized MX-BSop in situ gel (MX-BSop-Ig4) was further evaluated for gelling capacity, clarity, pH, viscosity, in vitro release, bio-adhesiveness, ex vivo permeation, toxicity, and antimicrobial properties. MX-BSop-Ig4 exhibited an optimum viscosity of 65.4 ± 5.3 cps in sol and 287.5 ± 10.5 cps in gel states. The sustained release profile (82 ± 4% in 24 h) was achieved with a Korsmeyer−Peppas kinetic release model (R2 = 0.9466). Significant bio-adhesion (967.9 dyne/cm2) was achieved in tear film. It also exhibited 1.2-fold and 2.8-fold higher permeation than MX-Ig and a pure MX solution, respectively. It did not show any toxicity to the tested tissue, confirmed by corneal hydration (77.3%), cornea histopathology (no internal changes), and a HET-CAM test (zero score). MX-BSop-Ig4 exhibited a significantly (p < 0.05) higher antimicrobial effect than pure MX against Staphylococcus aureus and Escherichia coli. The findings suggest that bilosome in situ gel is a good alternative to increase corneal residence time, as well as to improve therapeutic activity.

Development and Optimization of Hyaluronic Acid-Poloxamer In-Situ Gel Loaded with Voriconazole Cubosomes for Enhancement of Activity against Ocular Fungal Infection

Fungal eye infections are largely disseminated, especially in developing countries where they may leave over half a million people blind per year. The current study aims to boost the voriconazole antifungal efficiency via loading it as cubosomes (VZ-Cub) into hyaluronic acid and poloxamer-based ocular in situ gel. VZ-Cub were fabricated applying Box-Behnken design and employing phytantriol, poloxamer F127, and VZ amounts as independent variables. The produced nano vesicles were evaluated for the dependent variables of particle size (PS), entrapment efficiency (EE%), and transcorneal steady-state flux (Jss) of the VZ, and, the obtained optimal VZ-Cub was loaded into an in situ gel base to enhance its ocular residence time. The in situ gel formulation was tested for its gelation temperature, drug release behavior, transcorneal permeation effects, and antifungal activity. The optimized VZ-Cub consisted of 100 mg of phytantriol, 60 mg of poloxamer F127, and 21 mg of VZ. This formulation led to a minimum PS of 71 nm, an EE% of 66%, Jss value of 6.5 µg/(cm²·min), and stability index of 94 ± 2%. The optimized VZ-Cub-loaded in situ gel released 84% VZ after 12 h and yielded a 4.5-fold increase in drug permeation compared with the VZ aqueous dispersion. The antifungal activity, which was obtained by measuring the fungal growth inhibition zones, revealed that the VZ-Cub-loaded in situ gel formulation had a 3.89-fold increase in antifungal activity compared with the VZ dispersion. In summary, an ocular in situ gel loaded with VZ-Cub could be an effective novel nano-paradigm with enhanced transcorneal permeation and antifungal properties.

Repurposing Lovastatin Cytotoxicity against the Tongue Carcinoma HSC3 Cell Line Using a Eucalyptus Oil-Based Nanoemulgel Carrier

Tongue cancer is one of the most common carcinomas of the head and neck region. The antitumor activities of statins, including lovastatin (LV), and the essential oil of eucalyptus (Eu oil), have been adequately reported. The aim of this study was to develop a nanoemulgel containing LV combined with Eu oil that could then be made into a nanoemulsion and assessed to determine its cytotoxicity against the cell line human chondrosarcoma-3 (HSC3) of carcinoma of the tongue. An I-optimal coordinate-exchange quadratic mixture design was adopted to optimize the investigated nanoemulsions. The droplet size and stability index of the developed formulations were measured to show characteristics of the nanoemulsions. The optimized LV loaded self-nanoemulsifying drug delivery system (LV-Eu-SNEDDS) was loaded into the gelling agent Carbopol 934 to develop the nanoemulgel and evaluated for its rheological properties. The cytotoxic efficiency of the optimized LV-Eu-SNEDDS loaded nanoemulgel was tested for cell viability, and the caspase-3 enzyme test was used against the HSC3 cell line of squamous carcinoma of the tongue. The optimized nanoemulsion had a droplet size of 85 nm and a stability index of 93%. The manufactured nanoemulgel loaded with the optimum LV-Eu-SNEDDS exhibited pseudoplastic flow with thixotropic behavior. The developed optimum LV-Eu-SNEDDS-loaded nanoemulgel had the best half-maximal inhibitory concentration (IC₅₀) and caspase-3 enzyme values of the formulations developed for this study, and these features improved the ability of the nanoemulsion-loaded gel to deliver the drug to the investigated target cells. In addition, the in vitro cell viability studies revealed the synergistic effect between LV and Eu oil in the treatment of tongue cancer. These findings illustrated that the LV-Eu-SNEDDS-loaded gel formulation could be beneficial in the local treatment of tongue cancer.

Evaluation of the hepatoprotective effect of curcumin-loaded solid lipid nanoparticles against paracetamol overdose toxicity: Role of inducible nitric oxide synthase

Curcumin (Cur) is a natural compound that exhibited therapeutic effects against various liver injuries however Cur showed poor water solubility and bioavailability. This study aimed to design Cur-loaded solid lipid nanoparticles (SLNs) and to evaluate the hepatoprotective and antioxidant effects in a model of acute hepatotoxicity induced by paracetamol (PCM) overdose compared to the raw Cur and N-acetylcysteine (NAC). SLNs were prepared by emulsion/solvent evaporation method and 3² factorial design was employed. Wistar rats were divided into Control, PCM, PCM + NAC, PCM + raw Cur, and PCM + Cur-SLNs groups and treated orally for 14 days before receiving a single PCM dose. The Cur-loaded SLNs showed high entrapment efficiency % ranging between 69.1 and 92.1%, particle size (PS) between 217 and 506 nm, and zeta potential values between -17.9 and -25.5 mV. The in vivo results revealed that the PCM group exhibited deterioration of liver functions, pathological lesions on the liver tissues, severe oxidative stress, and increases in both the serum and hepatic iNOS levels. Remarkably, the PCM + Cur-SLNs group showed significantly better liver functions and tissue integrity compared to the PCM group. Furthermore, higher reduced glutathione and catalase but lower malondialdehyde and iNOS levels were observed. In conclusion, Cur-loaded SLNs effectively prevented the liver damage induced by PCM overdose through alleviating the oxidative stress and inhibiting the serum and hepatic iNOS expression in an effect comparable to NAC and better than raw Cur.

Preparation and Optimization of Garlic Oil/Apple Cider Vinegar Nanoemulsion Loaded with Minoxidil to Treat Alopecia

Alopecia areata is a scarless, localized hair loss disorder that is typically treated with topical formulations that ultimately only further irritate the condition. Hence, the goal of this study was to develop a nanoemulsion with a base of garlic oil (GO) and apple cider vinegar (APCV) and loaded with minoxidil (MX) in order to enhance drug solubilization and permeation through skin. A distance coordinate exchange quadratic mixture design was used to optimize the proposed nanoemulsion. Span 20 and Tween 20 mixtures were used as the surfactant, and Transcutol was used as the co-surfactant. The developed formulations were characterized for their droplet size, minoxidil steady-state flux (MX Jss) and minimum inhibitory concentration (MIC) against Propionibacterium acnes. The optimized MX-GO-APCV nanoemulsion had a droplet size of 110 nm, MX Jss of 3 μg/cm² h, and MIC of 0.275 μg/mL. The optimized formulation acquired the highest ex vivo skin permeation parameters compared to MX aqueous dispersion, and varying formulations lacked one or more components of the proposed nanoemulsion. GO and APCV in the optimized formulation had a synergistic, enhancing activity on the MX permeation across the skin membrane, and the percent permeated increased from 12.7% to 41.6%. Finally, the MX-GO-APCV nanoemulsion followed the Korsmeyer–Peppas model of diffusion, and the value of the release exponent (n) obtained for the formulations was found to be 1.0124, implying that the MX permeation followed Super case II transport. These results demonstrate that the MX-GO-APCV nanoemulsion formulation could be useful in promoting MX activity in treating alopecia areata.

The relevance of nanotechnology, hepato-protective agents in reducing the toxicity and augmenting the bioavailability of isotretinoin

Acne Vulgaris is one of the most common chronic inflammatory skin disorders that affect majority of teen-agers worldwide. Isotretinoin (ITT) is the drug of choice in the management of acne, but, it suffers from serious side-effects including hepatotoxicity, and some psychological disturbances following its oral intake. The objective of this study was to develop and optimize ITT loaded nanoemulsions (ITT-SNEDDS) and to incorporate resveratrol (RSV)in optimum formulation to decrease ITT side effects The ITT solubility was first tested in various essential oils, surfactants, and co-surfactants to select the essential nanoemulsion ingredients. Mixture design was applied to study the effect of independent variables and their interactions on the selected dependent responses. The developed ITT-SNEDDS were characterized for their globule size and ex vivo permeation. The optimized batch was further loaded with RSV and evaluated for in vitro and ex vivo permeation and for in vivo hepatotoxicity. The developed ITT-SNEDDS exhibited globule size below 300 nm, up to 272.27 ± 7.12 mcg/cm².h and 61.27 ± 2.83% of steady-state flux (J_SS) and permeability % respectively. Optimum formulation consisted of 0.15 g oil mixture, 0.6 g of surfactant (Labrasol), and 0.250 g co-surfactant (Transcutol). Permeability studies confirmed the enhanced permeation percentage of ITT (40.77 ± 1.18%), and RSV (29.94 ± 2.02%) from optimized formulation, with enhanced steady-state flux (J_SS). In vivo studies demonstrated the superior hepatoprotective activity of optimized formulation compared to a different drug formulations and marketed product. Therefore, RVS loaded ITT-SNEDDS might be a successful strategy for acne management with improved action, and minimum side effects.

Colloidal nanosystems with mucoadhesive properties designed for ocular topical delivery

Over the last years, the scientific interest about topical ocular delivery targeting the posterior segment of the eye has been increasing. This is probably due to the fact that this is a non-invasive administration route, well tolerated by patients and with fewer local and systemic side effects. However, it is a challenging task due to the external ocular barriers, tear film clearance, blood flow in the conjunctiva and choriocapillaris and due to the blood-retinal barriers, amongst other features. An enhanced intraocular bioavailability of drugs can be achieved by either improving corneal permeability or by improving precorneal retention time. Regarding this last option, increasing residence time in the precorneal area can be achieved using mucoadhesive polymers such as xyloglucan, poly(acrylate), hyaluronic acid, chitosan, and carbomers. On the other hand, colloidal particles can interact with the ocular mucosa and enhance corneal and conjunctival permeability. These nanosystems are able to deliver a wide range of drugs, including macromolecules, providing stability and improving ocular bioavailability. New pharmaceutical approaches based on nanotechnology associated to bioadhesive compounds have emerged as strategies for a more efficient treatment of ocular diseases. Bearing this in mind, this review provides an overview of the current mucoadhesive colloidal nanosystems developed for ocular topical administration, focusing on their advantages and limitations.

Tailoring of Retinyl Palmitate-Based Ethosomal Hydrogel as a Novel Nanoplatform for Acne Vulgaris Management: Fabrication, Optimization, and Clinical Evaluation Employing a Split-Face Comparative Study

AIM

Retinyl palmitate (RP), the most stable vitamin A derivative, is used to treat photoaging and other skin disorders. The need to minimize the adverse effects of topical drug administration has led to an enhanced interest in loading RP on ethosomes for topical drug delivery. The aim of the current study was to prepare and compare the performance of RP decorated ethosomal hydrogel with tretinoin cream in the treatment of acne vulgaris as an approach to improve drug efficacy and decrease its side effects.

METHODS

RP-loaded ethosomes were prepared using the injection sonication technique. A Box-Behnken design using Design Expert® software was used for the optimization of formulation variables. Particle size, zeta potential (ZP), entrapment efficiency percent (EE%), % drug release, and permeation over 24 h of different formulations were determined. The optimal formulation was incorporated into a hydrogel. Finally, the efficacy and tolerability of the optimized RP ethosomal hydrogel were clinically evaluated for acne treatment using a split-face comparative clinical study.

RESULTS

The optimized ethosomal RP showed particle size of 195.8±5.45 nm, ZP of -62.1±2.85 mV, EE% of 92.63±4.33%, drug release % of 96.63±6.81%, and drug permeation % of 85.98 ±4.79%. Both the optimized RP ethosomal hydrogel and tretinoin effectively reduced all types of acne lesions (inflammatory, non-inflammatory, and total lesions). However, RP resulted in significantly lower non-inflammatory and total acne lesion count than the marketed tretinoin formulation. Besides, RP-loaded ethosomes showed significantly improved tolerability compared to marketed tretinoin with no or minimal skin irritation symptoms.

CONCLUSION

RP ethosomal hydrogel is considerably effective in controlling acne vulgaris with excellent skin tolerability. Therefore, it represents an interesting alternative to conventional marketed tretinoin formulation for topical acne treatment.

Novel Chitosan-Coated Niosomal Formulation for Improved Management of Bacterial Conjunctivitis: A Highly Permeable and Efficient Ocular Nanocarrier for Azithromycin

In the present study, we aimed to formulate, optimize, and characterize azithromycin chitosan coated niosomes (AZM-CTS-NSM) as a novel colloidal system that increases precorneal residence period, eye permeation, and bioavailability. AZM-NSM was formulated via a modified thin-film hydration strategy and then coated with CTS. We assessed the influence of the cholesterol: surfactant molar ratio, CTS concentration, and surfactant type on particle diameter, entrapment, zeta potential, and NSM adhesion force to the corneal mucosal membrane and employed a central composite design (CCD). The resulting optimized AZM-CTS-NSM has a mean diameter of 376 nm, entrapment of 74.2%, surface charge of 32.1 mV, and mucoadhesion force of 3114 dyne/cm². The optimized AZM-CTS-NSM demonstrated a prolonged in vitro release behavior. When compared with commercial eye drops, the optimized AZM-CTS-NSM produced a 2.61-fold increase in the apparent permeability coefficient, significantly improving corneal permeability. Additionally, ocular irritation was assessed, with no major irritant effects found to be induced by the formulated NSM. Compared with AZM commercial drops, the optimized AZM-CTS-NSM revealed ˃ 3-fold increase in AZM concentration in the rabbit eyes. Collectively, these findings indicate that CTS-NSM is a potentially valuable ocular nanocarrier that could augment the efficacy of AZM.

Development of omega-3 loxoprofen-loaded nanoemulsion to limit the side effect associated with NSAIDs in treatment of tooth pain

The majority of newly developed drugs need to be incorporated with delivery systems to maximize their effect and minimize side effects. Nanoemulsions (NEs) are one type of delivery system that helps to improve the solubility and dissolution of drugs, attempting to enhance their bioavailability and onset of action. The objective of this investigation was to develop an omega-3 oil-based NE loaded with loxoprofen (LXP) to enhance its dissolution, in vitro release, and mucosal penetration and decrease its mucosal ulcerative effects when applied in an oral treatment. LXP-loaded NEs were formulated with varying levels of omega-3 oil (10–30%), surfactant polyoxyethylene-C21-ethers (laureth-21) (40–60%), and co-surfactant polyethylene glycol-40 hydrogenated castor oil (HCO-40) (30–50%) using an extreme vertices mixture design. The developed NEs were characterized for globule size and drug loading capacity. The optimal formulation was tested for in vitro drug release, ex vivo permeation, and ulcer index value. The developed NE acquired a globule size ranging 71–195 nm and drug loading capacity of 43–87%. Considering the results of the in vitro release study, the optimized NE formulation achieved 2.45-fold and 2-fold increases in drug permeation across tested mucosa compared to a marketed tablet and drug aqueous dispersion, respectively. Moreover, the optimum NE exhibited the best ulcer index in comparison to drug aqueous suspension and different formulations when tested in rats. Overall, this research highlights the capacity of NEs to deliver LXP with enhanced solubility, drug release, and permeation while effectively protecting the application site from side effects of the model drug.

Development, optimization and characterization of nanoemulsion loaded with clove oil-naftifine antifungal for the management of tinea

Tinea is a common superficial infection caused by keratinophylic fungi called dermatophytes. The objective of the current investigation was to develop and optimize a self-nanoemulsion drug delivery system (SENDDs) using clove oil loaded with naftifine (NF). Clove oil possesses good anti-inflammatory and antifungal properties that can support naftifine action. Box–Behnken designs were used to prepare plain and naftifine loaded SENDDs. The plain SENDDs were evaluated for their globule size. The medicated formulations (NF-CO-SENDDs) were characterized by measuring their globular size, ex vivo % NF permeated, level of interleukin-31 in rats, and antifungal activity. The optimum clove oil level was found to be 10–17%, while NF-CO-SENDDs formulations displayed globular sizes ranging from 119 to 310 nm. The statistical design confirmed the synergistic effect of clove oil and NF in the treatment of fungal infections, confirming that the anti-inflammatory effect of clove oil can counteract the side effects of NF. The optimized formulation composed of 14% clove oil, 12.5 mg Naftifine, and prepared with an Smix ratio equaling 3:1, exhibited good antifungal and anti-inflammatory activity, achieving up to 2-, 3-, 5.75-, and 2.74-fold increases in the amount of permeated NF, steady-state flux, permeability, and diffusion coefficients, respectively, compared with a commercial product. Moreover, the optimum formulation revealed an adequate zeta potential value of 28.31 ± 1.37 mV and showed reasonable stability with no or mild signs of skin sensitivity. Therefore, the designed nanoemulsions containing a combination of clove oil and naftifine could be considered promising delivery systems for the treatment of tinea.

Fabrication and Appraisal of Simvastatin via Tailored Niosomal Nanovesicles for Transdermal Delivery Enhancement: In Vitro and In Vivo Assessment

Simvastatin (SIM) is a HMG-CoA reductase inhibitor employed in the management of hyperlipidemia. However, its low bioavailability limits its clinical efficacy. The objective of this study was to overcome the poor bioavailability of SIM via the transdermal application of a SIM-loaded niosomal gel. Niosomes loaded with SIM were fabricated by means of the thin-film hydration method and optimized through a 3³-factorial design utilizing Design Expert^® software. The prepared niosomes were evaluated for entrapment efficiency (EE%), zeta potential, vesicle size, and cumulative percentage of drug release. The optimum niosomal formulation was loaded on the gel and evaluated for physical properties such as color, clarity, and homogeneity. It was also evaluated for spreadability, and the cumulative % drug release. The best niosomal gel formula was appraised for ex vivo permeation as well as pharmacokinetic study. The SIM-loaded niosomes showed EE% between 66.7–91.4%, vesicle size between 191.1–521.6 nm, and zeta potential ranged between −0.81–+35.6 mv. The cumulative percentage of drug released was ranged from 55% to 94% over 12 h. SIM-loaded niosomal gels were clear, homogenous, spreadable, and the pH values were within the range of physiological skin pH. Furthermore, about 73.5% of SIM was released within 24 h, whereas 409.5 µg/cm² of SIM passed through the skin over 24 h in the ex vivo permeation study. The pharmacokinetic study revealed higher AUC_0–∞ and Cmax with topical application of SIM-loaded niosomal gel compared to topical SIM gel or oral SIM suspension. The topical application of SIM-loaded niosomal gel ascertained the potential percutaneous delivery of SIM.

Niosomal Drug Delivery Systems for Ocular Disease-Recent Advances and Future Prospects

The eye is a complex organ consisting of several protective barriers and particular defense mechanisms. Since this organ is exposed to various infections, genetic disorders, and visual impairments it is essential to provide necessary drugs through the appropriate delivery routes and vehicles. The topical route of administration, as the most commonly used approach, maybe inefficient due to low drug bioavailability. New generation safe, effective, and targeted drug delivery systems based on nanocarriers have the capability to circumvent limitations associated with the complex anatomy of the eye. Nanotechnology, through various nanoparticles like niosomes, liposomes, micelles, dendrimers, and different polymeric vesicles play an active role in ophthalmology and ocular drug delivery systems. Niosomes, which are nano-vesicles composed of non-ionic surfactants, are emerging nanocarriers in drug delivery applications due to their solution/storage stability and cost-effectiveness. Additionally, they are biocompatible, biodegradable, flexible in structure, and suitable for loading both hydrophobic and hydrophilic drugs. These characteristics make niosomes promising nanocarriers in the treatment of ocular diseases. Hereby, we review niosome based drug delivery approaches in ophthalmology starting with different preparation methods of niosomes, drug loading/release mechanisms, characterization techniques of niosome nanocarriers and eventually successful applications in the treatment of ocular disorders.

Proniosomal Microcarriers: Impact of Constituents on the Physicochemical Properties of Proniosomes as a New Approach to Enhance Inhalation Efficiency of Dry Powder Inhalers

Proniosomes are free-flowing systems with coating carriers, which developed as a method for improving the drug flow and pulmonary delivery. Extensive research on proniosomes was done to enhance the dry powder inhalers (DPI)'s inhalation performance. This research aimed at studying the impact of lactose-mannitol mixture additives on the proniosome's physicochemical properties as a method for improving the inhalation efficiency of DPI. Vismodegib has been employed as a compound model. Box-Behnken design has been employed to prepare different proniosomes formulae by incorporating various (A) span 60 concentrations, (B) lactose concentrations and (C) mannitol: total carrier mixture. The measured responses were vesicle size (R₁), %release (R₂), Carr's index (R₃) and %recovery (R₄). The results displayed that R₁ and R₄ were significantly antagonistic to C and significantly synergistic to both A and B while R₂ and R₃ were significantly synergistic to C and significantly antagonistic to both A and B. The optimal formula was selected for its aerodynamic behaviour, cytotoxic activity and bioavailability assessment. The optimal formula resulted in better Vismodegib lung deposition, cytotoxic activity and relative bioavailability. This novel formula could be a promising carrier for sustained delivery of drugs via the pulmonary route.

Latanoprost niosomes as a sustained release ocular delivery system for the management of glaucoma

Objective: Glaucoma is a leading cause of irreversible blindness worldwide. Whereas latanoprost is one of the most effective drugs in glaucoma treatment, its eye drops need frequent application leading to lack of patient adherence. This study aimed to develop a patient-friendly niosome-in-gel system for the sustained ocular delivery of latanoprost.Methods: Niosomes were prepared by the reverse-phase evaporation technique and optimized for different formulation parameters, such as cholesterol/surfactant and drug/surfactant ratios. Selected niosomal formulations were incorporated into different gels and their viscosity and drug release kinetics were evaluated. Optimal niosomal gel was evaluated in vivo in rabbits' eyes for irritation potential and ability to reduce intraocular pressure.Results: FT-IR studies showed that there were nonspecific interactions between latanoprost and different niosomal components leading to drug encapsulation efficiency ≥88%. Latanoprost encapsulation efficiency increased with the drug/surfactant ratio and encapsulation efficiency ∼98% was obtained at a ratio of 50%. Pluronic^® F127 had the best ability to sustain drug release from the niosomes. In rabbits' eyes, this gel was free of toxic and irritant effects and reduced intraocular pressure over a period of three days, which was significantly longer than that of commercial latanoprost eye drops.Conclusion: Latanoprost niosomal Pluronic^® F127 gel may find applications in glaucoma management.

Nanosized nasal emulgel of resveratrol: preparation, optimization, in vitro evaluation and in vivo pharmacokinetic study

Nano-emulgel has become one of the most significant controlled release systems, which has the advantages of both gels and nano-emulsions. This work aims at the formulation of nasal nano-emulgel for resveratrol, employing carbopol 934 and poloxamer 407 as the gelling agents. The optimum nano-emulsion was determined through further characterization of the selected system. The nasal nano-emulgel was prepared and tested for the in vitro release, the release kinetics, FTIR, ex vivo permeation, nasal mucosa toxicity, and in vivo pharmacokinetic study. The optimum nano-emulsion consisted of Tween 20, Capryol 90, and Transcutol at a ratio of (54.26: 23.81: 21.93%v/v), and it exhibited transmittance of 100%, resveratrol solubility of 159.9 ± 6.4 mg/mL, globule size of 30.65 nm. The in vitro resveratrol released from nano-emulsion and nasal nano-emulgel was 96.17 ± 4.43% and 78.53 ± 4.7%, respectively. Ex vivo permeation was sustained during 12 h up to 63.95 ± 4.7%. The histopathological study demonstrated that the formula is safe and tolerable to the nasal mucosa. C_max and AUC _(0-∞) of resveratrol obtained after nasal administration of nasal nano-emulgel was 2.23 and 8.05 times, respectively. Similarly, T_max was increased up to 3.67 ± 0.82 h. The optimized nasal nano-emulgel established intranasal safety and bioavailability enhancement so it is considered as a well-designed system to target the brain.

Vancomycin-loaded niosomes integrated within pH-sensitive in-situ forming gel for treatment of ocular infections while minimizing drug irritation

Objectives

The aim of the current study was to minimize ocular irritation and prolong the pharmacological action of vancomycin via formulation into nanosized spherical niosomes loaded into pH-sensitive in-situ forming gel.

Methods

Stability and rheological behaviour of the various gelling systems were evaluated. The ability of the selected system to eradicate methicillin-resistant Staphylococcus aureus (MRSA) infections was examined in vitro and in vivo. Draize technique was also used to assess ocular irritation in rabbits.

Key findings

Nanosized spherical niosomes loaded with vancomycin at high entrapment efficiency were prepared and integrated into polymeric solution that forms gel in situ upon instillation into the eye, to allow for a further increase in the ocular residence time. In MRSA-infected rabbits, there were 180- and 2.5-fold increases in the antibacterial efficacy after treatment with the vancomycin niosomal gels in comparison with the untreated animals and the animals treated with the vancomycin free drug solution, respectively.

Conclusions

The developed formulations demonstrated promising in-vivo biocompatibility and antibacterial efficacy, signifying their potential application as ophthalmic preparation to overcome ocular infections induced by resistant bacterial strains while minimizing drug irritation and improving patient compliance.

Development, Optimization, and In Vitro/In Vivo Characterization of Enhanced Lipid Nanoparticles for Ocular Delivery of Ofloxacin: the Influence of Pegylation and Chitosan Coating

This study aims to investigate whether modification of solid lipid nanoparticles (SLNs) with chitosan (CTS) and polyethylene glycol (PEG) coatings enhances corneal retention time and transcorneal bioavailability. Ofloxacin (OFLOX) was selected as the model drug because of its potential benefits for the treatment of local eye infections. The OFLOX-CTS-PEG-SLN was prepared by a modified emulsion/solvent evaporation technique. A central composite design was implemented to investigate the influence of total lipid/drug ratio, surfactant concentration, PEG stearate concentration in the lipid mixture, and CTS concentration on size, entrapment, transcorneal permeation, and adhesion to the corneal mucosal membrane. The optimized OFLOX-CTS-PEG-SLN was characterized for OFLOX cumulative percentage released in simulated tear fluid and permeated across the excised bovine corneal membrane. Moreover, nanoparticle morphology, eye irritation via histopathological analysis, and OFLOX concentration in the ocular fluids and tissues were determined. A total lipid/drug ratio of 19:1, Tween 80 of 2%, PEG stearate concentration in the lipid mixture (% w/w) of 2.6%, and CTS concentration (% w/v) of 0.23% produced 132.9 nm particles entrapping 74.8% of the total drug added. The particles detached from the corneal membrane at a force of 3700 dyne/cm². The %OFLOX released from the optimized nanoparticles was 63.3, and 66% of the drug permeated after 24 h. Compared to Oflox® drops, the optimized OFLOX-CTS-PEG-SLN exhibited similar tolerability but two- to threefold higher concentrations in the eyes of rabbits. Coating of SLN with chitosan and PEG augments the ocular bioavailability of OFLOX by increasing transcorneal permeation and enhancing mucoadhesion strength.

Intranasal niosomes of nefopam with improved bioavailability: preparation, optimization, and in-vivo evaluation

OBJECTIVE

One of the greatest challenges drug formulation is facing is poor bioavailability via oral route. In this regard, nasal drug delivery has been commonly used as an alternative route to improve drug bioavailability. Nefopam hydrochloride (NF) is an analgesic drug that suffers from poor bioavailability due to extensive metabolism in liver. Accordingly, the goal of the present study was to improve NF bioavailability via niosomal-based formulation designed for intranasal delivery.

MATERIALS AND METHODS

Vesicles were developed by mixing surfactants (Span 20, Span 40, Span 80, and Span 85) at four molar ratios of 1:1, 1:2, 1:3, and 1:4 of cholesterol to surfactant. Entrapment efficiency, particle size, zeta potential, release percentage, ex-vivo permeation parameters, and niosomes' stability were determined. Also, the pharmacokinetic parameters of the optimized formula in in-situ gel base were measured in rats.

RESULTS

Niosomes showed entrapment efficiency .80%, particle size ,550 nm, and zeta potential ranging from -16.8±0.13 to -29.7±0.15. The produced vesicles showed significantly higher amounts of drug permeated across nasal mucosa (2.5 folds) and prolonged NF release compared with NF solution. Stability studies of optimum formula showed nonsignificant changes in niosomes parameters over a storage period of 6 months. The in-vivo studies showed a 4.77-fold increase in bioavailability of optimized nasal niosomes compared with oral solution of drug.

CONCLUSION

The obtained results revealed the great ability of the produced NF-loaded nio-somes to enhance drug penetration through nasal mucosa and improve its relative bioavailability compared with NF oral solution.