Nanoemulsions as vehicles for transdermal delivery of aceclofenac

Pseudo-ternary phase diagram based PEGylated nano-dispersion of linezolid to promote wound regeneration: an in vitro and in vivo evaluation

Open wounds are prone to bacterial infiltration mostly resistant strains like methicillin-resistant Staphylococcus aureus (MRSA), which affects healing of open wounds. Topical linezolid nano-dispersion using essential oils as nanoemulgel can increase solubility of drug and bypass side-effects like GI-irritation of oral administration. Pseudo-ternary phase diagram was built to optimise nanoemulsion. Surfactant/co-surfactant mixture (3:1), deionised water and Oilmix (4:1) with drug were vortexed and then ultrasonicated. 1% carbopol gel of optimised nanoemulsion was prepared and characterised, exposed to antimicrobial study, cytocompatibility study using HEK293 cell-line, and in vivo wound healing study using rat excision model. Histological study was performed to confirm growth of stratum corneum. Optimised formulation has particle size (244.6 ± 178.66 nm), polydispersity index (25%), entrapment efficiency (92.3 ± 3.38%) and in vitro drug release (87.58 ± 4.16%) best fitted in Korsmeyer-Peppas kinetics model. Nanoemulgel F6 (0.2%w/w) was found with viscosity of 5345 ± 6 cP constituting a very excellent antimicrobial effect against MRSA. HEK293 cells had shown good cytocompatibility with formulation. The wound contraction rate was 99.66 ± 0.57% at day 15 on daily application of nanoemulgel and stratum corneum was almost fully regenerated. The developed nanoemulgel has potential antimicrobial efficacy and can promote wound healing.

Exploring the potential of antifungal-loaded proniosomes to consolidate corneal permeation in fungal keratitis: A comprehensive investigation from laboratory characterization to microbiological evaluation

This work aimed to prepare Terconazole loaded proniosomes (TCZ-PNS) utilizing modified coacervation technique for the management of fungal keratitis. Terconazole (TCZ) is a potent antifungal with poor aqueous solubility posing intricacies in its incorporation in ocular formulations. A 23 factorial design was adopted to probe independent formulation variables including A: Lecithin: cholesterol ratio, B: Surfactant: cholesterol ratio and C: Span® 80 contribution (% of total SAA). The formulae, generated by the design, were prepared and scrutinized regarding entrapment efficiency (%EE), particle size (PS), polydispersity index (PDI) and zeta potential (ZP). Numerical desirability algorithms selected an optimum TCZ-PNS which boasted plausible %EE (89.51 % ± 0.94 %), nanoscale vesicles consistent with TEM measurements (247.9 ± 0.42 nm), a sufficiently high ZP (-43.42 ± 0.85 mV), and an in-vitro biphasic release profile that remained stable even after Gamma irradiation and short-term storage. The transcorneal ex-vivo permeation of TCZ-PNS was higher than that of TCZ suspension (≈ 2-fold). The formulation was further evaluated for pH, corneal hydration threshold, and histopathological safety, confirming its suitability for ocular application. Confocal laser microscopy revealed substantial corneal uptake (approximately twice as deep as of TCZ suspension). Additionally, microbiological assessments of the optimal TCZ-PNS compared to TCZ suspension demonstrated an inhibition zone nearly 50 % larger, a significantly lower MIC and MFC (64-fold reduction), and enhanced biofilm inhibition activity across most tested concentrations. These findings suggest that TCZ-PNS could be a propitious treatment choice to deeply deliver antifungal therapy for the eradication of deeply rooted and inaccessible fungal keratitis.

Terconazole loaded edge-activated hybrid elastosome for revamped corneal permeation in ocular mycosis: In-vitro characterization, statistical optimization, microbiological assessment, and in-vivo evaluation

Herein, we investigated the preparation and characterization of Terconazole loaded edge-activated hybrid elastosome (TCN-EHE) adopting thin film hydration technique for the treatment of ocular mycosis. Terconazole (TCN) is a broad spectrum antimycotic agent suffering from sparse aqueous solubility impeding its use in ophthalmic preparations. The scrutinized formulation variables namely X1: Surfactant: Edge activator ratio (SAA: EA), X2: Pluronic® L121 contribution (% of total SAA) and X3: EA concentration (%w/v) were optimized adopting D-optimal design. Ten runs were prepared and characterized regarding their entrapment efficiency, particle size, polydispersity index and zeta potential. An optimized formula was generated, with high desirability, exhibited satisfactory entrapment efficiency, nanoscaled particle size aligning with TEM, plausible zeta potential and bi-phasic release pattern which were not altered after short-term storage. The optimized TCN-EHE displayed 1.94-fold enhanced ex-vivo corneal permeation flux. Safety was ratified through measured corneal hydration level, pH and histopathological evaluation. In-vivo corneal uptake visualized by confocal laser microscopy demonstrated 2.7-fold deeper penetration. Moreover, Superior antifungal activity has been demonstrated displaying 37 % bigger zone of inhibition, 8-fold lower minimum inhibitory and minimum fungal concentration alongside significantly higher biofilm inhibition activity at all tested concentrations for the optimized TCN-EHE compared to TCN suspension. Conclusively, we could prospect that TCN-EHE might be a revamped therapeutic alternative for the delivery of poorly soluble antimycotic agents for the combat of ocular mycosis.

Formulation and evaluation of nanoemulsions from Jasminum officinale essential oil for controlling postharvest browning and maintaining quality in jasmine (Jasminum sambac) flowers

The jasmine (Jasminum sambac (L.) Aiton) flower has delicate petals, resulting in rapid browning after harvest. The aim of this study was to search for an innovative postharvest treatment for delaying browning of jasmine petals using plant essential oils. J. officinale L. f. var. grandiflorum (L.) essential oil was found to reduce peroxidase activity in jasmine flower by 44.21% in the in vitro condition. The antioxidant activities and chemical composition of J. officinale essential oil were subsequently characterized. The essential oil exhibited the ability to scavenge 2,2-diphenyl-1-picrylhydrazil (DPPH) radicals with a 50% inhibition (EC50) value of 6.72 ± 0.89 mg/mL, a chelating effect with EC50 value of 7.42 ± 1.59 mg/mL, and reducing power with EC0.5 value of 14.89 ± 0.73 mg/mL. GC-MS analysis detected 29 compounds in the oil, with benzyl alcohol (20.68%) and benzyl acetate (19.87%) predominating. As plant essential oils have restricted water solubility, an oil-in-water emulsion was formulated using a spontaneous emulsification method. The resulting J. officinale essential oil naonoemulsion (JEN) had an oil droplet size of 70.2 ± 0.39 nm and a narrow polydispersity index. In vivo testing confirmed the inhibitory effects of JEN on jasmine flower browning and relevant enzyme activities. Jasmine flowers were soaked in various concentrations of JEN for 5 min, packed in polyethylene plastic bags, and stored in a refrigerator at 10 ± 3°C with relative humidity 66 ± 5%. Flowers treated with 1 and 2 mg/mL JEN showed effective delay of petal browning and maintained good quality with minimum flower opening index, high freshness score, and high color retention index. JEN treatment also reduced phenylalanine ammonia lyase (PAL), polyphenol oxidase (PPO), and peroxidase (POD) activities, indicating postponement of the browning process. In addition, scanning electron microscopy micrographs of treated flower epidermis cells revealed delayed cell wall collapse, indicating retention of intact cells. Taken together, these results support JEN as a potential preventative of enzymatic browning and hence petal browning in jasmine flower.

Dynamic Behavior of the Glassy and Supercooled Liquid States of Aceclofenac Assessed by Dielectric and Calorimetric Techniques

Aceclofenac (ACF), a non-steroidal anti-inflammatory drug, was obtained in its amorphous state by cooling from melt. The glass transition was investigated using dielectric and calorimetric techniques, namely, dielectric relaxation spectroscopy (DRS), thermally stimulated depolarization currents (TSDC), and conventional and temperature-modulated differential scanning calorimetry (DSC and TM-DSC). The dynamic behavior in both the glassy and supercooled liquid states revealed multiple relaxation processes. Well below the glass transition, DRS was able to resolve two secondary relaxations, γ and β, the latter of which was also detectable by TSDC. The kinetic parameters indicated that both processes are associated with localized motions within the molecule. The main (α) relaxation was clearly observed by DRS and TSDC, and results from both techniques confirmed a non-Arrhenian temperature dependence of the relaxation times. However, the glass transition temperature (Tg) extrapolated from DRS data significantly differed from that obtained via TSDC, which in turn showed reasonable agreement with the calorimetric Tg (Tg-DSC = 9.2 °C). The values of the fragility index calculated by the three experimental techniques converged in attributing the character of a moderately fragile glass former to ACF. Above the α relaxation, TSDC showed a well-defined peak. In DRS, after "removing" the high-conductivity contribution using ε' derivative analysis, a peak with shape parameters αHN = βHN = 1 was also detected. The origin of these peaks, found in the full supercooled liquid state, has been discussed in the context of structural and dynamic heterogeneity. This is supported by significant differences observed between the FTIR spectra of the amorphous and crystalline samples, which are likely related to aggregation differences resulting from variations in the hydrogen bonds between the two phases. Additionally, the pronounced decoupling between translational and relaxational motions, as deduced from the low value of the fractional exponent x = 0.72, derived from the fractional Debye-Stokes-Einstein (FDSE) relationship, further supports this interpretation.

Understanding Microemulsions and Nanoemulsions in (Trans)Dermal Delivery

Continuously explored in pharmaceuticals, microemulsions and nanoemulsions offer drug delivery opportunities that are too significant to ignore, namely safe delivery of clinically relevant drug doses across biological membranes. Their effectiveness as drug vehicles in mucosal and (trans)dermal delivery is evident from the volume of published literature. Commonly, their ability to enhance skin permeation is attributed to dispersion size, a characteristic closely related to solubilization capacity. However, the literature falls short on distinctions between microemulsions and nanoemulsions for definitions, behavior, or specific differences in their mechanisms of action in (trans)dermal delivery. The focus is typically on surfactant/cosurfactant ratio and droplet size but the role of mesostructures or the effect of cosolvent (Csol), oil (O) or water (W) on permeation profile remain poorly explained. Towards a deeper understanding of these vehicles in (trans)dermal drug delivery, this review begins with their conceptual and practical distinctions before delving into the published works for less obvious but potentially important underlying mechanisms; notably composition and the competitive positioning of system constituents in the resulting microstructures and subsequent effect(s) these may have on skin structures and drug permeability. For practical purposes, this review focuses on formulation systems based on ternary diagrams with commonly accepted non-ionic surfactants, cosurfactants, cosolvents, and oils used in pharmaceutical applications.

Gelatin emulsion gels loaded with host defence peptides for the treatment of antibiotic-resistant infections

The surge in multidrug-resistant bacteria against conventional antibiotics is a rapidly developing global health crisis necessitating novel infection management strategies. Host defence peptides (HDPs), also known as antimicrobial peptides (AMPs), offer a promising alternative to traditional antibiotics, but their practical translation is limited by their susceptibility to proteases and potential off-site cytotoxicity. In this paper, we investigate the feasibility of using gelatin emulsion gels (GELs), prepared using a water-in-oil (W/O) method, for the delivery of HDPs DJK-5 and IDR-1018 to improve their clinical utility. DJK-5-loaded GELs exhibited complete eradication of planktonic Methicillin-resistant Staphylococcus aureus (MRSA) at 4 - and 24-h intervals. Similarly, IDR-1018-loaded GELs demonstrated almost complete killing of MRSA and Escherichia coli (E. coli) after 4 h. Importantly, none of the GEL formulations investigated exhibited in vitro cytotoxicity. Overall, these HDP loaded GELs are a promising solution for the treatment of antibiotic-resistant infections.

Solubility and thermodynamic analysis of aceclofenac in different {Carbitol + water} mixtures at various temperatures

The solubility and thermodynamic properties of the anti-inflammatory drug aceclofenace (ACF) have been assessed in a range of {2-(2-ethoxyethoxy)ethanol (Carbitol) + water} combinations at temperatures ranging from 298.2 K to 318.2 K and atmospheric pressure of 101.1 kPa. The shake flask method was employed to determine the solubility of ACF, and various models including "van't Hoff, Apelblat, Buchowski-Ksiazczak λh, Yalkowsky-Roseman, Jouyban-Acree, and Jouyban-Acree-van't Hoff models" were used to validate the results. The computational models demonstrated a strong correlation with the experimental ACF solubility data, as indicated by the error values of < 3.0%. In the compositions of {Carbitol + water}, the ACF mole fraction solubility was enhanced by temperature and Carbitol mass fraction. The solubility of ACF in mole fraction was found to be lowest in pure water (1.07 × 10- 6 at 298.2 K), and highest in pure Carbitol (1.04 × 10- 1 at 318.2 K). Based on the positive values of the calculated thermodynamic parameters, the dissolution of ACF was determined to be "endothermic and entropy-driven" in all of the {Carbitol + water} solutions that were studied. It was also observed that enthalpy controls the solvation of ACF in solutions containing {Carbitol + water}. ACF-Carbitol had the strongest molecular interactions in contrast to ACF-water. Based on the results of this study, Carbitol holds significant potential for enhancing the solubility of ACF in water.

Skin Penetration and Permeation Properties of Transcutol® in Complex Formulations

Percutaneous delivery is explored as alternative pathway for addressing the drawbacks associated with the oral administration of otherwise efficacious drugs. Short of breaching the skin by physical means, the preference goes to formulation strategies that augment passive diffusion across the skin. One such strategy lies in the use of skin penetration and permeation enhancers notably of hydroxylated solvents like propylene glycol (PG), ethanol (EtOH), and diethylene glycol monoethyl ether (Transcutol®, TRC). In a previous publication, we focused on the role of Transcutol® as enhancer in neat or diluted systems. Herein, we explore its' role in complex formulation systems, including patches, emulsions, vesicles, solid lipid nanoparticles, and micro or nanoemulsions. This review discusses enhancement mechanisms associated with hydroalcoholic solvents in general and TRC in particular, as manifested in multi-component formulation settings alongside other solvents and enhancers. The principles that govern skin penetration and permeation, notably the importance of drug diffusion due to solubilization and thermodynamic activity in the vehicle (formulation), drug solubilization and partitioning in the stratum corneum (SC), and/or solvent drag across the skin into deeper tissue for systemic absorption are discussed. Emphasized also are the interplay between the drug properties, the skin barrier function and the formulation parameters that are key to successful (trans)dermal delivery.

Enhancing the efficacy of fluconazole against Leishmania major: Formulation and evaluation of FLZ-nanoemulsions for topical delivery

BACKGROUND

Cutaneous Leishmaniasis (CL) remains a significant public health concern, particularly in the tropical and subtropical regions. Present treatment options for CL such as Fluconazole (FLZ) face limitations, including low solubility and bioavailability. This study aimed to address these challenges by investigating the use of nano-emulsions (NEs) to enhance the efficacy of FLZ against Leishmania major(L.major).

MATERIALS AND METHODS

FLZ-NEs were formulated with oleic acid, Tween-20, and ethanol using low-energy emulsification at various surfactant/co-surfactant ratios. Subsequently, a comprehensive analysis was conducted to assess the physicochemical characteristics of the samples. This analysis encompassed stability, zeta potential, pH, viscosity, refractive index, and droplet size. We then studied the anti-parasitic properties of these optimized FLZ-NEs both in vitro and in vivo.

RESULTS

The selected nano-emulsion (NE) formulation (2 % oleic acid, 20 % Tween 20, 10 % ethyl alcohol) showcased desirable properties like small droplet size (10.51 ± 0.24 nm), low dispersity (0.19 ± 0.03), and zeta potential value (- 0.41 ± 0.17 mV), key for stability and targeted drug delivery. This optimal formulation translated into remarkable efficacy. In vitro, FLZ-NEs demonstrated a threefold increase in their ability to combat promastigotes and a remarkable thirtyfold increase in their ability to combat amastigotes. Additionally, they demonstrated a ninefold advantage in their ability to specifically target parasites within infected macrophages, thereby attacking the infection site. These promising in vitro results translated into improved outcomes in vivo. Compared to other chemicals studied, FLZ-NE-treated mice showed decreased disease severity, weight growth, and quicker ulcer healing. It was further supported by histopathological research, which showed reduced tissue damage linked to Leishmania infection.

CONCLUSION

These findings show the potential of nanotechnology-based drug delivery in improving anti-leishmanial treatment.

Myco-fabricated silver nanoparticle by novel soil fungi from Saudi Arabian desert and antimicrobial mechanism

Biological agents are getting a noticeable concern as efficient eco-friendly method for nanoparticle fabrication, from which fungi considered promising agents in this field. In the current study, two fungal species (Embellisia spp. and Gymnoascus spp.) were isolated from the desert soil in Saudi Arabia and identified using 18S rRNA gene sequencing then used as bio-mediator for the fabrication of silver nanoparticles (AgNPs). Myco-synthesized AgNPs were characterized using UV-visible spectrometry, transmission electron microscopy, Fourier transform infrared spectroscopy and dynamic light scattering techniques. Their antibacterial activity against Escherichia coli, Pseudomonas aeruginosa, Staphylococcus aureus, and Klebsiella pneumoniae were investigated. In atrial to detect their possible antibacterial mechanism, Sodium dodecyl sulfate (SDS-PAGE) and TEM analysis were performed for Klebsiella pneumoniae treated by the myco-synthesized AgNPs. Detected properties of the fabricated materials indicated the ability of both tested fungal strains in successful fabrication of AgNPs having same range of mean size diameters and varied PDI. The efficiency of Embellisia spp. in providing AgNPs with higher antibacterial activity compared to Gymnoascus spp. was reported however, both indicated antibacterial efficacy. Variations in the protein profile of K. pneumoniae after treatments and ultrastructural changes were observed. Current outcomes suggested applying of fungi as direct, simple and sustainable approach in providing efficient AgNPs.

In vitro and Ex vivo study targeting the development of a Lavandula stoechas L. (Ustukhuddūs) loaded Unani Transdermal patch: Implication of Unani Medicine in the treatment of Nisyan (Dementia)

Ustukhuddūs (Lavandula stoechas L.) has been extensively used orally and topically in treating various neurological disorders, including dementia. The optimum potential of traditional dosage forms of Ustukhuddūs is limited for various reasons. Transdermal drug delivery system (TDDS) is a novel means of drug delivery and is known to overcome the drawbacks associated with traditional dosage forms. The current study aimed at fabricating and evaluating Ustukhuddūs hydro-alcoholic extract (UHAE) and essential oil (UEO) loaded matrix-type transdermal patches having a combination of hydrophilic - hydroxyl propyl methyl cellulose (HPMC) and hydrophobic - ethyl cellulose (EC) polymers. ATR-FTIR, DSC, XRD, and SEM analysis were carried out to study drug-polymer interactions, confirming the formation of developed patches and drug compatibility with excipients. We assessed the fabricated patches to evaluate their physicochemical properties, in vitro drug release, and permeation characteristics via ex vivo experiments. The physicochemical characteristics of patches showcased the development of good and stable films with clarity, smoothness, homogeneity, optimum flexibility and free from causing skin irritancy or sensitization. In vitro drug release and ex vivo permeation profile of developed patches were evaluated employing Franz diffusion cells. UHAE and UEO patches exhibited a cumulative drug release of 81.61 and 85.24 %, respectively, in a sustained-release manner and followed non-Fickian release mechanisms. The ex vivo permeation data revealed 66.82 % and 76.41 % of drug permeated from UHAE and UEO patches, respectively. The current research suggests that the formulated patches are more suitable for TDDS and hold potential significance in the treatment of dementia, contributing to enhanced patient compliance, thereby highlighting the implication of Unani Medicine in Nisyan (Dementia) treatment.

Hypothesizing the Oleic Acid-Mediated Enhanced and Sustained Transdermal Codelivery of Pregabalin and Diclofenac Adhesive Nanogel: A Proof of Concept

Pregabalin (PG) and diclofenac diethylamine (DEE) are anti-inflammatory molecules that are effective in relieving inflammation and pain associated with musculoskeletal disorders, arthritis, and post-traumatic pain, among others. Intravenous and oral delivery of these two molecules has their limitations. However, the transdermal route is believed to be an alternate viable option for the delivery of therapeutic molecules with desired physicochemical properties. To this end, it is vital to understand the physicochemical properties of these drugs, dosage, and strategies to enhance permeation, thereby surmounting the associated constraints and concurrently attaining a sustained release of these therapeutic molecules when administered in combination. The present work hypothesizes the enhanced permeation and sustained release of pregabalin and diclofenac diethylamine across the skin, entrapped in the adhesive nano-organogel formulation, including permeation enhancers. The solubility studies of pregabalin and diclofenac diethylamine in combination were performed in different permeation enhancers. Oleic acid was optimized as the best permeation enhancer based on in vitro studies. Pluronic organogel containing pregabalin and diclofenac diethylamine with oleic acid was fabricated. Duro-Tak® (87-2196) was added to the organogel formulation as a pressure-sensitive adhesive to sustain the release profile of these two therapeutic molecules. The adhesive organogel was characterized for particle size, scanning electron microscopy, and contact angle measurement. The HPLC method developed for the quantification of the dual drug showed a retention time of 3.84 minutes and 9.69 minutes for pregabalin and diclofenac, respectively. The fabricated nanogel adhesive formulation showed the desired results with particle size and contact angle of 282 ± 57 nm and ≥120⁰, respectively. In vitro studies showed the percentage cumulative release of 24.90 ± 4.65% and 33.29 ± 4.81% for pregabalin and diclofenac, respectively. In order to accomplish transdermal permeation, the suggested hypothesis of fabricating PG and DEE nano-organogel in combination with permeation enhancers will be a viable drug delivery method. In comparison to a traditional gel formulation, oleic acid as a permeation enhancer increased the penetration of both PG and DEE from the organogel formulation. Notably, the studies showed that the use of pressure-sensitive adhesives enabled the sustained release of both PG and DEE.Therefore, the results anticipated the hypothesis that the transdermal delivery of adhesive PG and DEEbased nanogel across the human skin can be achieved to inhibit inflammation and pain.

Tween 80-Based Self-Assembled Mixed Micelles Boost Valsartan Transdermal Delivery

Valsartan (Val) is an important antihypertensive medication with poor absorption and low oral bioavailability. These constraints are due to its poor solubility and dissolution rate. The purpose of this study was to optimize a mixed micelle system for the transdermal delivery of Val in order to improve its therapeutic performance by providing prolonged uniform drug levels while minimizing drug side effects. Thin-film hydration and micro-phase separation were used to produce Val-loaded mixed micelle systems. A variety of factors, including the surfactant type and drug-to-surfactant ratio, were optimized to produce micelles with a low size and high Val entrapment efficiency (EE). The size, polydispersity index (PDI), zeta potential, and drug EE of the prepared micelles were all measured. The in vitro drug release profiles were assessed using dialysis bags, and the permeation through abdominal rat skin was assessed using a Franz diffusion cell. All formulations had high EE levels exceeding 90% and low particle charges. The micellar sizes ranged from 107.6 to 191.7 nm, with average PDI values of 0.3. The in vitro release demonstrated a uniform slow rate that lasted one week with varying extents. F7 demonstrated a significant (p < 0.01) transdermal efflux of 68.84 ± 3.96 µg/cm2/h through rat skin when compared to the control. As a result, the enhancement factor was 16.57. In summary, Val-loaded mixed micelles were successfully prepared using two simple methods with high reproducibility, and extensive transdermal delivery was demonstrated in the absence of any aggressive skin-modifying enhancers.

Fabrication of solid lipid nanoparticles-based patches of paroxetine and their ex-vivo permeation behaviour

Paroxetine is not suitable for oral administration due to its extensive first-pass metabolism, thus resulting in less bioavailability. This study aimed to prepare novel paroxetine-loaded solid lipid nanoparticles (SLNs) based sustained-release transdermal patches to overcome these problems by enhancing drug absorption and bioavailability. Nine formulations of paroxetine SLNs were prepared by the hot melt-homogenization method using different concentrations of glycerol monostearate (Kolliwax) and Tween 80. Then these prepared SLNs were incorporated in a matrix type transdermal patch having a matrix of ethyl cellulose and polyvinyl pyrrolidone in 3:2 with polyvinyl alcohol. The SLNs showed a particle size range of 113-230 nm and an entrapment efficiency of 85.14%. The SLNs showed sustained paroxetine release (77.86-95.63% release) up to 48 h. FTIR studies showed no interaction between drug and formulation components. Paroxetine is evenly distributed in an amorphous form in SLNs, as demonstrated by DSC as well as PXRD analysis. SLNs formulated patches showed higher drug permeation through the skin than drug-based transdermal patches., Draize patch test revealed no sign of erythema after applying paroxetine-loaded SLN patches (score 0) as observed with the marketed product. The developed SLNs based transdermal patches showed increased permeability and sustained release behaviour.

Nanoemulsion: An Emerging Novel Technology for Improving the Bioavailability of Drugs

The pharmaceutical sector has made considerable strides recently, emphasizing improving drug delivery methods to increase the bioavailability of various drugs. When used as a medication delivery method, nanoemulsions have multiple benefits. Their small droplet size, which is generally between 20 and 200 nanometers, creates a significant interfacial area for drug dissolution, improving the solubility and bioavailability of drugs that are weakly water-soluble. Additionally, nanoemulsions are a flexible platform for drug administration across various therapeutic areas since they can encapsulate hydrophilic and hydrophobic medicines. Nanoemulsion can be formulated in multiple dosage forms, for example, gels, creams, foams, aerosols, and sprays by using low-cost standard operative processes and also be taken orally, topically, topically, intravenously, intrapulmonary, intranasally, and intraocularly. The article explores nanoemulsion formulation and production methods, emphasizing the role of surfactants and cosurfactants in creating stable formulations. In order to customize nanoemulsions to particular medication delivery requirements, the choice of components and production techniques is crucial in assuring the stability and efficacy of the finished product. Nanoemulsions are a cutting-edge technology with a lot of potential for improving medication bioavailability in a variety of therapeutic contexts. They are a useful tool in the creation of innovative pharmaceutical formulations due to their capacity to enhance drug solubility, stability, and delivery. Nanoemulsions are positioned to play a crucial role in boosting medication delivery and enhancing patient outcomes as this field of study continues to advance.

β-Caryophyllene-Loaded Microemulsion-Based Topical Hydrogel: A Promising Carrier to Enhance the Analgesic and Anti-Inflammatory Outcomes

Musculoskeletal pain and inflammation can vary from localised pain like pain in the shoulders and neck to widespread pain like fibromyalgia, and as per estimates, around 90% of humans have experienced such pain. Oral non-steroidal anti-inflammatory drugs (NSAIDs) are frequently prescribed for such conditions but are associated with concerns like gastric irritation and bleeding. In the present study, a microemulsion-based gel comprising β-caryophyllene, isopropyl myristate, Tween 80, and normal saline was prepared as a topical option for managing topical pain and inflammation. The globules of the microemulsion were below 100 nm with a zetapotential of around -10 mV. The drug entrapment was >87% with a drug loading of >23%. The permeation studies established better skin permeation (20.11 ± 0.96 μg cm-2 h-1) and retention of the drug (4.96 ± 0.02%) from the developed system vis-à-vis the conventional product (9.73 ± 0.35 μg cm-2 h-1; 1.03 ± 0.01%). The dermatokinetic studies established the better pharmacokinetic profile of the bioactive in the epidermis and dermis layers of the skin. The anti-inflammatory potential in carrageenan-induced rat paw oedema was more pronounced than the conventional product (~91% vis-à-vis ~77%), indicating a better pharmacodynamic outcome from the developed system. The nanotechnology-based natural bioactive product with improved efficacy and drug loading can provide a better alternative for the management of musculoskeletal pain.

Exploring Nanocarriers as Treatment Modalities for Skin Cancer

Cancer is a progressive disease of multi-factorial origin that has risen worldwide, probably due to changes in lifestyle, food intake, and environmental changes as some of the reasons. Skin cancer can be classified into melanomas from melanocytes and nonmelanoma skin cancer (NMSC) from the epidermally-derived cell. Together it constitutes about 95% of skin cancer. Basal cell carcinoma (BCC) and cutaneous squamous cell carcinoma (CSCC) are creditworthy of 99% of NMSC due to the limited accessibility of conventional formulations in skin cancer cells of having multiple obstacles in treatment reply to this therapeutic regime. Despite this, it often encounters erratic bioavailability and absorption to the target. Nanoparticles developed through nanotechnology platforms could be the better topical skin cancer therapy option. To improve the topical delivery, the nano-sized delivery system is appropriate as it fuses with the cutaneous layer and fluidized membrane; thus, the deeper penetration of therapeutics could be possible to reach the target spot. This review briefly outlooks the various nanoparticle preparations, i.e., liposomes, niosomes, ethosomes, transferosomes, transethosomes, nanoemulsions, and nanoparticles technologies tested into skin cancer and impede their progress tend to concentrate in the skin layers. Nanocarriers have proved that they can considerably boost medication bioavailability, lowering the frequency of dosage and reducing the toxicity associated with high doses of the medication.

Strategies for Improving Transdermal Administration: New Approaches to Controlled Drug Release

In this work, we aim to address several strategies to improve transdermal drug delivery, such as iontophoresis, sonophoresis, electroporation and micron. We also propose a review of some transdermal patches and their applications in medicine. TDDs (transdermal patches with delayed active substances) are multilayered pharmaceutical preparations that may contain one or more active substances, of which, systemic absorption is achieved through intact skin. The paper also presents new approaches to the controlled release of drugs: niosomes, microemulsions, transfersomes, ethosomes, but also hybrid approaches nanoemulsions and microns. The novelty of this review lies in the presentation of strategies to improve the transdermal administration of drugs, combined with their applications in medicine, in light of pharmaceutical technological developments.

Fabrication, characterization, antimicrobial, toxicity and potential drug-delivery studies of PEGylated Sesamum indicum oil based nanoemulsion system

Background

The actively mutating properties of disease-causing pathogens and GI intolerance associated with certain antibiotics among other challenges necessitated the adoption of colloidal system for drug delivery. Nanoemulsions (Ciprofloxacin (Cp) -loaded and non-drug loaded) were prepared by spontaneous emulsification method, characterized using Cryo-TEM, FTIR and Zetasizer. Antimicrobial activities were carried out using agar well diffusion method on Klebsiella pneumoniae and Bacillus subtilis. The in-vitro and dermal toxicological assessment were carried out using adult Wistar rats.

Results

The Cryo-TEM micrographs showed spherical morphology while zetasizer results showed polydispersity index (PDI), mean droplet size and zeta potential (ZP) of 0.553, 124.3 ± 0.29 nm and − 15.3 mV respectively for non-drug loaded sesame oil-based emulsion (SOAB). While 0.295, 244.8 ± 0.33 nm and − 5.54 mV were recorded for Cp-loaded sesame oil-based emulsion (SOAB + Cp). The effective voltage charge of the emulsions was 147.4 V. FTIR results of Cp recorded O–H adsorption value of 3429 cm−1, while SOAB and SOAB + Cp showed superimposition at 3427.76 cm−1 showing no drug-excipient interactions. No skin irritation was observed after 14 days of skin corrosion assessment. No significant difference (p > 0.05) in body weight gain of both test and control animals, the treatment did not cause any observable alterations in blood-chemistry parameters and hematological indices. Photomicrographs of liver and heart shows an uncompromised histological architecture.

Conclusion

The finding of the study shows a skin friendly, nanosized, spherical negatively charged emulsion with no cardiotoxic, hematotoxic and hepatotoxic effects on Wistar rats, and as such appears promising as a safe vehicle for drug delivery.

Graphical Abstract

Delivery of Active Peptides by Self-Healing, Biocompatible and Supramolecular Hydrogels

Supramolecular and biocompatible hydrogels with a tunable pH ranging from 5.5 to 7.6 lead to a wide variety of formulations useful for many different topical applications compatible with the skin pH. An in vitro viability/cytotoxicity test of the gel components demonstrated that they are non-toxic, as the cells continue to proliferate after 48 h. An analysis of the mechanical properties demonstrates that the hydrogels have moderate strength and an excellent linear viscoelastic range with the absence of a proper breaking point, confirmed with thixotropy experiments. Two cosmetic active peptides (Trifluoroacetyl tripeptide-2 and Palmitoyl tripeptide-5) were successfully added to the hydrogels and their transdermal permeation was analysed with Franz diffusion cells. The liquid chromatography-mass spectrometry (HPLC-MS) analyses of the withdrawn samples from the receiving solutions showed that Trifluoroacetyl tripeptide-2 permeated in a considerable amount while almost no transdermal permeation of Palmitoyl tripeptide-5 was observed.

Comparative study on the topical and transdermal delivery of diclofenac incorporated in nano-emulsions, nano-emulgels, and a colloidal suspension

Transdermal delivery of active pharmaceutical ingredients (APIs) can be challenging, since the skin possesses a rate-limiting barrier, which may be overcome when APIs possess certain ideal physicochemical properties. The lack thereof would require that APIs be included in drug delivery vehicles to enhance skin permeation. Hence, diclofenac was incorporated into various drug delivery vehicles (i.e., nano-emulsions, nano-emulgels, and a colloidal suspension containing drug-loaded nanoparticles) to investigate the transdermal delivery thereof, while nano-emulsions and nano-emulgels had varying concentrations of evening primrose oil (EPO). The aim of the study was to compare the topical and transdermal diclofenac delivery from the different types of vehicles and to investigate the influence the different EPO concentrations had on diclofenac delivery. After characterization, membrane release studies were performed (to determine whether the API was successfully released from the vehicle) followed by in vitro skin diffusion studies and tape stripping (to establish whether the vehicles assisted the API in reaching the target site (transdermal delivery)). Lastly, cytotoxicity studies were conducted via methyl thiazolyl tetrazolium (MTT) and neutral red (NR) assays on human keratinocyte (HaCaT) cells. Results showed minimal cytotoxic effects at concentrations equivalent to that which had permeated through the skin, while the membrane release and in vitro skin diffusion studies indicated that the nano-emulsions and the 10% EPO vehicles increased API release and diffusion when compared to the other vehicles. However, the colloidal suspension had the highest concentrations of API within the skin. Hence, all the vehicles were non-toxic and effectively delivered diclofenac through the transdermal route.

Preparation and Characterization of Lidocaine-Loaded, Microemulsion-Based Topical Gels

Microemulsion-based gels (MBGs) were prepared for transdermal delivery of lidocaine and evaluated for their potential for local anesthesia. Lidocaine solubility was measured in various oils, and phase diagrams were constructed to map the concentration range of oil, surfactant, cosurfactant, and water for oil-in-water (o/w) microemulsion (ME) domains, employing the water titration method at different surfactant/cosurfactant weight ratios. Refractive index, electrical conductivity, droplet size, zeta potential, pH, viscosity, and stability of fluid o/w MEs were evaluated. Carbomer^® 940 was incorporated into the fluid drug-loaded MEs as a gelling agent. Microemulsion-based gels were characterized for spreadability, pH, viscosity, and in-vitro drug release measurements, and based on the results obtained, the best MBGs were selected and subsequently subjected to ex-vivo rat skin permeation anesthetic effect and irritation studies. Data indicated the formation of nano-sized droplets of MEs ranging from 20 - 52 nm with a polydispersity of less than 0.5. In-vitro release and ex-vivo permeation studies on MBGs showed significantly higher drug release and permeation in comparison to the marketed topical gel. Developed MBG formulations demonstrated greater potential for transdermal delivery of lidocaine and advantage over the commercially available gel product, and therefore, they may be considered as potential vehicles for the topical delivery of lidocaine.

Development of nanoemulsion of antiviral drug for brain targeting in the treatment of neuro-AIDS

Background

Delivery of drugs via the nasal route directly to the brain utilizing the olfactory pathway is purportedly known to be a more efficient method to deliver neuro-therapeutics to the brain by circumventing the BBB, thereby increasing the bioavailability of these drugs in the brain. The main objective of the project work is to improve the bioavailability of the antiretroviral drug and to minimize the side effects of this therapy which are observed at the higher side in the chronic HIV treatment. The advantage of nasal drug delivery is its noninvasiveness and self-administration. Nanoformulation provides fast onset of action and helps to achieve site-specific delivery. In the current work, nanoemulsion formulation was developed with a ternary phase system. In vitro characterization of nanoemulsion was performed.

Result

Optimized batch B2 had a zeta potential of − 18.7 mV showing a stable emulsion system and a particle size of 156.2 nmin desirable size range. Batch B2 has the least variation in globule size with PDI 0.463. Results from ex vivo studies revealed that developed nanoemulsion (B2) possessed a higher rate of drug release compared to other formulations.

Conclusion

Phase diagrams indicated more width of the nanoemulsion region with an increase in surfactant ratio. Stable nanoemulsion was prepared with a combination of surfactant and co-surfactants. Nanoemulsions could prove one of the best alternatives for brain delivery of potent medications.

Graphical Abstract

Nanolipogel Loaded with Tea Tree Oil for the Management of Burn: GC-MS Analysis, In Vitro and In Vivo Evaluation

The GC-MS analysis of tea tree oil (TTO) revealed 38 volatile components with sesquiterpene hydrocarbons (43.56%) and alcohols (41.03%) as major detected classes. TTO efficacy is masked by its hydrophobicity; nanoencapsulation can address this drawback. The results showed that TTO-loaded solid lipid nanoparticles (SLN1), composed of glyceryl monostearate (2% w/w) and Poloxamer188 (5% w/w), was spherical in shape with a core-shell microstructure. TTO-SLN1 showed a high entrapment efficiency (96.26 ± 2.3%), small particle size (235.0 ± 20.4 nm), low polydispersity index (0.31 ± 0.01), and high negative Zeta potential (−32 mV). Moreover, it exhibited a faster active agent release (almost complete within 4 h) compared to other formulated TTO-SLNs as well as the plain oil. TTO-SLN1 was then incorporated into cellulose nanofibers gel, isolated from sugarcane bagasse, to form the ‘TTO-loaded nanolipogel’ which had a shear-thinning behavior. Second-degree thermal injuries were induced in Wistar rats, then the burned skin areas were treated daily for 7 days with the TTO-loaded nanolipogel compared to the unmedicated nanolipogel, the TTO-loaded conventional gel, and the normal saline (control). The measurement of burn contraction proved that TTO-loaded nanolipogel exhibited a significantly accelerated skin healing, this was confirmed by histopathological examination as well as quantitative assessment of inflammatory infiltrate. This study highlighted the success of the proposed nanotechnology approach in improving the efficacy of TTO used for the repair of skin damage induced by burns.

Fabrication, In Vitro, and In Vivo Assessment of Eucalyptol-Loaded Nanoemulgel as a Novel Paradigm for Wound Healing

Wounds are the most common causes of mortality all over the world. Topical drug delivery systems are more efficient in treating wounds as compared to oral delivery systems because they bypass the disadvantages of the oral route. The aim of the present study was to formulate and evaluate in vitro in vivo nanoemulgels loaded with eucalyptol for wound healing. Nanoemulsions were prepared using the solvent emulsification diffusion method by mixing an aqueous phase and an oil phase, and a nanoemulgel was then fabricated by mixing nanoemulsions with a gelling agent (Carbopol 940) in a 1:1 ratio. The nanoemulgels were evaluated regarding stability, homogeneity, pH, viscosity, Fourier-transform infrared spectroscopy (FTIR), droplet size, zeta potential, polydispersity index (PDI), spreadability, drug content, in vitro drug release, and in vivo study. The optimized formulation, F5, exhibited pH values between 5 and 6, with no significant variations at different temperatures, and acceptable homogeneity and spreadability. F5 had a droplet size of 139 ± 5.8 nm, with a low polydispersity index. FTIR studies showed the compatibility of the drug with the excipients. The drug content of F5 was 94.81%. The percentage of wound contraction of the experimental, standard, and control groups were 100% ± 0.015, 98.170% ± 0.749, and 70.846% ± 0.830, respectively. Statistically, the experimental group showed a significant difference (p < 0.03) from the other two groups. The results suggest that the formulated optimized dosage showed optimum stability, and it can be considered an effective wound healing alternative.

Investigation of Factors Influencing Formation of Nanoemulsion by Spontaneous Emulsification: Impact on Droplet Size, Polydispersity Index, and Stability

Interest in nanoemulsion technology has increased steadily in recent years for its widespread applications in the delivery of pharmaceuticals, nutraceuticals, and cosmeceuticals. Rational selection of the composition and the preparation method is crucial for developing a stable nanoemulsion system with desired physicochemical characteristics. In the present study, we investigate the influence of intricate factors including composition and preparation conditions that affect characteristic parameters and the stability of the nanoemulsion formation prepared by the spontaneous emulsification method. Octanoic acid, capryol 90, and ethyl oleate were selected to represent oil phases of different carbon–chain lengths. We explored the impact of the addition mode of the oil–S_mix phase and aqueous phase, vortexing time, K_m (surfactant/cosurfactant) ratio, and the replacement of water by buffers of different pH as an aqueous system. The phase behavior study showed that the S_mix phase had a significant impact on the nanoemulsifying ability of the nanoemulsions composed of oil phases of varying carbon-chain lengths. The mode of mixing of the oil–S_mix phase to the aqueous phase markedly influenced the mean droplet size and size distribution of the nanoemulsions composed of oil phases as capryol 90. Vortexing time also impacted the mean droplet size and the stability of the generated nanoemulsion system depending on the varying carbon-chain length of the oil phase. The replacement of the water phase by aqueous buffers of pH 1.2, 5.5, 6.8, and 7.4 has altered the mean droplet size and size distribution of the nanoemulsion system. Further, the K_m ratio also had a significant influence on the formation of the nanoemulsion system. The findings of this investigation are useful in understanding how the formulation composition and process parameters of the spontaneous emulsification technique are responsible for affecting the physicochemical characteristics and stability of the nanoemulsion system composed of oil of varying carbon-chain (C₈-C₁₈) length.

Development and Characterization of Azithromycin-Loaded Microemulsions: A Promising Tool for the Treatment of Bacterial Skin Infections

In recent years, the treatment of bacterial skin infections has been considered a major healthcare issue due to the growing emergence of antibiotic-resistant strains of Staphylococcus aureus. The incorporation of antibiotics in appropriate nanosystems could represent a promising strategy, able to overcome several drawbacks of the topical treatment of infections, including poor drug retention within the skin. The present work aims to develop microemulsions containing azithromycin (AZT), a broad-spectrum macrolide antibiotic. Firstly, AZT solubility in various oils, surfactants and co-surfactants was assessed to select the main components. Subsequently, microemulsions composed of vitamin E acetate, Labrasol^® and Transcutol^® P were prepared and characterized for their pH, viscosity, droplet size, zeta potential and ability to release the drug and to promote its retention inside porcine skin. Antimicrobial activity against S. aureus methicillin-resistant strains (MRSA) and the biocompatibility of microemulsions were evaluated. Microemulsions showed an acceptable pH and were characterized by different droplet sizes and viscosities depending on their composition. Interestingly, they provided a prolonged release of AZT and promoted its accumulation inside the skin. Finally, microemulsions retained AZT efficacy on MRSA and were not cytotoxic. Hence, the developed AZT-loaded microemulsions could be considered as useful nanocarriers for the treatment of antibiotic-resistant infections of the skin.

Beneath the Skin: A Review of Current Trends and Future Prospects of Transdermal Drug Delivery Systems

The ideal drug delivery system has a bioavailability comparable to parenteral dosage forms but is as convenient and easy to use for the patient as oral solid dosage forms. In recent years, there has been increased interest in transdermal drug delivery (TDD) as a non-invasive delivery approach that is generally regarded as being easy to administer to more vulnerable age groups, such as paediatric and geriatric patients, while avoiding certain bioavailability concerns that arise from oral drug delivery due to poor absorbability and metabolism concerns. However, despite its many merits, TDD remains restricted to a select few drugs. The physiology of the skin poses a barrier against the feasible delivery of many drugs, limiting its applicability to only those drugs that possess physicochemical properties allowing them to be successfully delivered transdermally. Several techniques have been developed to enhance the transdermal permeability of drugs. Both chemical (e.g., thermal and mechanical) and passive (vesicle, nanoparticle, nanoemulsion, solid dispersion, and nanocrystal) techniques have been investigated to enhance the permeability of drug substances across the skin. Furthermore, hybrid approaches combining chemical penetration enhancement technologies with physical technologies are being intensively researched to improve the skin permeation of drug substances. This review aims to summarize recent trends in TDD approaches and discuss the merits and drawbacks of the various chemical, physical, and hybrid approaches currently being investigated for improving drug permeability across the skin.

Nanoemulsion-based dosage forms for the transdermal drug delivery applications: A review of recent advances

INTRODUCTION

Nanoemulsion-based drug delivery approaches have witnessed massive acceptance over the years and acquired a significant foothold owing to their tremendous benefits over the others. It has widely been used for transdermal delivery of hydrophobic and hydrophilic drugs with solubility, lipophilicity, and bioavailability issues.

AREAS COVERED

The review highlights the recent advancements and applications of transdermal nanoemulsions. Their utilities and characteristics, clinical pertinence showcasing intellectual properties and advancements, potential in treating disorders accompanying liquid, semisolid, and solid dosage forms, the ability to modulate a drug's physicochemical properties, and regulatory status are thoroughly summarized.

EXPERT OPINION

Despite tremendous therapeutic utilities and extensive investigations, this field of transdermal nanoemulsion-based technologies yet tackles several challenges such as optimum use of surfactant mixtures, economic burden due to high energy consumption during production, lack of concrete regulatory requirement, etc. Provided with the concrete guidelines on the safe use of surfactants, stability, use of scalable and economical methods, and the use of NE as a transdermal system would solve the purpose best as nanoemulsion shows remarkable improvement in drug release profiles and bioavailability of many drugs. Nevertheless, a better understanding of nanoemulsion technology holds a promising outlook and would land more opportunities and better delivery outcomes.

Anti-rheumatic activity of topical nanoemulsion containing bee venom in rats

PURPOSE

Bee Venom (BV) has been used to treat rheumatoid arthritis (RA) for many centuries. However, its clinical use is limited by pain and fear of bee stings/injection. Nanoemulsions (NEs) are nanocarriers that are able to help their content(s) penetrate through the skin. They also act as drug reservoirs on the skin to provide an efficient, sustained-release vehicle.

METHODS

In this paper, we present the development of a stable water-in-oil NE to help passing BV through the animal skin when used topically.

RESULTS

Particle size of NE was 12.7 to 29.8 nm for NEs containing 0 to 150 µg/ml BV. Also, its anti-inflammatory effects were evaluated in rat models of type II collagen-induced arthritis. Topical administration of NEs containing 18.75 or 9.37 μg/ml BV were able to significantly (p<0.05) reduce inflammation in the rat paws compared to the blank and control groups.

CONCLUSION

Our findings demonstrated the efficacy of NEs containing BV to reduce inflammation caused by RA animal model.

Overcoming hydrolytic degradation challenges in topical delivery: non-aqueous nano-emulsions

INTRODUCTION

Non-aqueous nano-emulsions (NANEs) are colloidal lipid-based dispersions with nano-sized droplets formed by mixing two immiscible phases, none of which happens to be an aqueous phase. Their ability to incorporate water and oxygen sensitive drugs without any susceptibility to degradation makes them the optimum dosage form for such candidates. In NANEs, polar liquids or polyols replace the aqueous phase while surfactants remain same as used in conventional emulsions. They are a part of the nano-emulsion family albeit with substantial difference in composition and application.

AREAS COVERED

The present review provides a brief insight into the strategies of loading water-sensitive drugs into NANEs. Further advancement in these anhydrous systems with the use of solid particulate surfactants in the form of Pickering emulsions is also discussed.

EXPERT OPINION

NANEs offer a unique platform for delivering water-sensitive drugs by loading them in anhydrous formulation. The biggest advantage of NANEs vis-à-vis the other nano-cargos is that they can also be prepared without using equipment-intensive techniques. However, the use of NANEs in drug delivery is quite limited. Looking at the small number of studies available in this direction, a need for further research in this field is required to explore this delivery system further.

Nanoemulsions as Ophthalmic Drug Delivery Systems

Nanoemulsions are liquid-in-liquid dispersion with a droplet size of about 100 nm. They have a transparent appearance, high rate of bioavailability, and increased shelf life. Nanoemulsions mainly consist of oil, water, surfactant, and cosurfactant and can be prepared by high- and low-energy methods. Diluted nanoemulsions are utilized for the delivery of ophthalmic drugs due to their capability to penetrate the deep layers of the ocular structure, provide a sustained release effect, and reduce the frequency of administration and side effects. These nanoemulsions are subjected to certain tests, such as safety, stability, pH profile, rheological studies, and so on. Cationic nanoemulsions are prepared for topical ophthalmic delivery of active ingredients from cationic agents to increase the drug residence time on the ocular surface, reducing their clearance from the ocular surface and improving drug bioavailability. This review article summarizes the main characteristics of nanoemulsions, ophthalmic nanoemulsions, and cationic nanoemulsions and their components, methods of preparation, and the evaluation parameters for ophthalmic nanoemulsions.

Glimepiride-Loaded Nanoemulgel; Development, In Vitro Characterization, Ex Vivo Permeation and In Vivo Antidiabetic Evaluation

Glimepiride (GMP), an oral hypoglycemic agent is extensively employed in the treatment of type 2 diabetes. Transdermal delivery of GMP has been widely investigated as a promising alternative to an oral approach but the delivery of GMP is hindered owing to its low solubility and permeation. The present study was designed to formulate topical nanoemulgel GMP system and previously reported solubility enhanced glimepiride (GMP/βCD/GEL-44/16) in combination with anti-diabetic oil to enhance the hypoglycemic effect. Nanoemulsions were developed using clove oil, Tween-80, and PEG-400 and were gelled using xanthan gum (3%, w/w) to achieve the final nanoemulgel formulations. All of the formulations were evaluated in terms of particle size, zeta potential, pH, conductivity, viscosity, and in vitro skin permeation studies. In vivo hypoglycemic activity of the optimized nanoemulgel formulations was evaluated using a streptozocin-induced diabetes model. It was found that a synergistic combination of GMP with clove oil improved the overall drug permeation across the skin membrane and the hypoglycemic activity of GMP. The results showed that GMP/βCD/GEL-44/16-loaded nanoemulgel enhanced the in vitro skin permeation and improved the hypoglycemic activity in comparison with pure and marketed GMP. It is suggested that topical nano emulsion-based GMP gel and GMP/βCD/GEL-44/16 could be an effective alternative for oral therapy in the treatment of diabetes.

Azacarbazole n-3 and n-6 polyunsaturated fatty acids ethyl esters nanoemulsion with enhanced efficacy against Plasmodium falciparum

Alternative therapies are necessary for the treatment of malaria due to emerging drug resistance. However, many promising antimalarial compounds have poor water solubility and suffer from the lack of suitable delivery systems, which seriously limits their activity. To address this problem, we synthesized a series of azacarbazoles that were evaluated for antimalarial activity against D10 (chloroquine-sensitive) and W2 (chloroquine-resistant) strains of P. falciparum. The most active compound, 9H-3-azacarbazole (3), was encapsulated in a novel o/w nanoemulsion consisting of ethyl esters of polyunsaturated fatty acids n-3 and n-6 obtained from flax oil as the oil phase, Smix (Tween 80 and Transcutol HP) and water. This formulation was further analyzed using transmission electron microscopy, dynamic light scattering and in vitro and in vivo studies. It was shown that droplets of the 3-loaded nanosystem were spherical, with satisfactory stability, without cytotoxicity towards fibroblasts and intestinal cell lines at concentrations corresponding to twice the IC50 for P. falciparum. Moreover, the nanoemulsion with this type of oil phase was internalized by Caco-2 cells. Additionally, pharmacokinetics demonstrated rapid absorption of compound 3 (tmax = 5.0 min) after intragastric administration of 3-encapsulated nanoemulsion at a dose of 0.02 mg/kg in mice, with penetration of compound 3 to deep compartments. The 3-encapsulated nanoemulsion was found to be 2.8 and 4.2 times more effective in inhibiting the D10 and W2 strains of the parasite, respectively, compared to non-encapsulated 3. Our findings support a role for novel o/w nanoemulsions as delivery vehicles for antimalarial drugs.

Cubosomes as a Potential Oral Drug Delivery System for Enhancing the Hepatoprotective Effect of Coenzyme Q10

Coenzyme Q10 (CoQ10) acts as an antioxidant that protects the cells by preventing lipid peroxidation. Owing to its low solubility, CoQ10 has shown poor delivery properties and poor bioavailability. The aim of this study is to develop CoQ10 loaded cubosomes in order to enhance its oral delivery and hepatoprotective activity. Cubosomes are cubic nanostructured systems resulting from the colloidal dispersion of cubic liquid crystalline structure in water. CoQ10 loaded cubosomes were prepared using poloxamer 407 and glyceryl monooleate at three weight ratios (1:2.5, 1:5 and 1:7.5) and were further characterized. They were investigated for their hepatoprotective effect in thioacetamide (TAA) induced hepatotoxicity in Wistar rats. The developed CoQ10 cubosomes exhibited moderate to high entrapment efficiency percentages (44.69-75.96%), nanometric dimensions (132.4-223.2 nm), and negatively charged zeta potential values (<-21.3). In-vitro release profiles showed a sustained release of CoQ10 from the developed cubosomes up to 48 h. In-vivo study revealed an improved hepatoprotective effect of CoQ10 cubosomes via reducing liver enzymes, nitric oxide and malondialdehyde as well as elevating phosphoinositide 3-kinase, catalase and glutathione peroxidase, compared to plain drug. These results were in good agreement with histopathological investigations. Consequently, the developed cubosomes showed a potential effect in enhancing the hepatoprotective activity of CoQ10.

Physical Enhancement? Nanocarrier? Current Progress in Transdermal Drug Delivery

A transdermal drug delivery system (TDDS) is a method that provides drug adsorption via the skin. TDDS could replace conventional oral administration and blood administration because it is easily accessible. However, it is still difficult to design efficient TDDS due to the high barrier property of skin covered with stratum corneum, which inhibits the permeation of drug molecules. Thus far, TDDS methods by applying physical stimuli such as microneedles and chemical stimuli such as surfactants have been actively developed. However, it has been hard to avoid inflammation at the administration site because these methods partially destroy the skin tissue. On the other hand, TDDS with nanocarriers minimizing damage to the skin tissues has emerged together with the development of nanotechnology in recent years. This review focuses on current trends in TDDS.

Nanoemulsion: A Novel Drug Delivery Approach for Enhancement of Bioavailability

BACKGROUND

Poor bioavailability and solubility of drugs in aqueous phase are the most important problems of newly developed chemical entities that can be improved by nanoemulsion.

OBJECTIVES

BCS class II and IV which are poorly soluble in water demonstrate various problems in conventional dosage forms. For the improvement of solubility, bioavailability and getting the best therapeutic effect of poorly soluble drugs nanoemulsion is the best solution.

METHODS

Nanoemulsion are thermodynamically unstable isotropic system with droplet size 1-100 nm in which two immiscible fluids are combined together to form one phase by using an emulsifying agent. Nanoemulsion can be designed to promote the bioavailability of API by trapping them inside.

RESULTS

Nanoemulsion can be developed in many dosage forms such as oral, parenteral, topical, ophthalmic dosage form in large scale using common operation at a very low cost. Large range of lipophilic drugs can be easily incorporated in nanoemulsion.

CONCLUSION

In this review, attention is focused on the type of nanoemulsions, their advantages over other dosage form, method for their preparation, characterization, applications and patents in various fields.

Formulation design and evaluation of aceclofenac nanogel for topical application

Aim: The current study aimed to explore the feasibility of the nanoemulgel for the topical delivery of aceclofenac. Materials & methods: Solubility of drugs in the formulation systems was determined and aceclofenac nanoemulsion (NE) was prepared by high-pressure homogenization technique. Carbopol 940 was added as a gelling agent. Results & conclusion: The composition of optimized NE consist of labrafil along with triacetin as oil, tween 80 and cremophor EL in combination as a surfactant and transcutol HP along with PEG 400 and ethanol as cosurfactant. The droplet size of the NE was 141.1 ± 3.65 nm, with low polydispersity index and negative zeta potential. The aceclofenac-nanoemulgel was developed using carbopol 940 and exhibited excellent permeation in comparison to the marketed sample.

Therapeutic Nanoemulsion: Concept to Delivery

Nanoemulsions (NEs) or nanometric-scaled emulsions are transparent or translucent, optically isotropic and kinetically stable heterogeneous system of two different immiscible liquids namely, water and oil stabilized with an amphiphilic surfactant having droplet size ranges up to 100 nm. They offer a variety of potential interests for certain applications: improved deep-rooted stability; excellent optical clarity; and, enhanced bioavailability due to its nanoscale of particles. Though there is still comparatively narrow insight apropos design, development, and optimization of NEs, which mainly stems from the fact that conventional characteristics of emulsion development and stabilization only partly apply to NEs. The contemporary article focuses on the nanoemulsion dosage form journey from concept to key application in drug delivery. In addition, industrial scalability of the nanoemulsion, as well as its presence in commercial and clinical practice, are also addressed.

Oleic Acid Vesicles as a new Approach for Transdermal Delivery of Econazole Nitrate: Development, Characterization, and In-vivo Evaluation in Wistar rats

BACKGROUND

Cutaneous candidiasis is a deep-seated skin fungal infection that is most commonly observed in immunocompromised patients. This fungal infection is conventionally treated with various formulations like gels and creams which are having different side effects and least therapeutic efficacy. Hence, it becomes necessary to develop a novel carrier system for the treatment of this deep-seated skin fungal infection. Econazole nitrate is the most widely used antifungal for the treatment of cutaneous candidiasis, therefore, in present research work we developed and evaluated econazole nitrate loaded oleic acid vesicles for treatment of cutaneous candidiasis through transdermal route.

METHODS

Econazole nitrate loaded oleic acid vesicles were prepared by thin-film hydration and characterized for drug entrapment, vesicle size, zeta potential, polydispersity index (PDI), Fourier Transform-infrared spectroscopy (FT-IR), differential scanning calorimetry (DSC), X-ray diffraction (XRD) analysis. Furthermore, the oleic acid vesicular gel was evaluated for ex-vivo skin permeation/retention and in-vitro and in-vivo antifungal activity in Wistar rats.

RESULTS

Econazole nitrate loaded oleic acid vesicles showed high encapsulation of drug (74.76 ± 3.0%), acceptable size (373.4 ± 2.9 nm), and colloidal characteristics (PDI = 0.231 ± 0.078, zeta potential = -13.27 ± 0.80 mV). The oleic acid vesicular gel showed high skin permeation (Transdermal flux = 61.98 ± 2.45 μg/cm2/h), skin retention (35.90 ± 2.06%), in-vitro, and in-vivo antifungal activity compared to marketed cream (EcodermR) of econazole nitrate for a prolonged period of time (4 days).

CONCLUSION

Developed econazole nitrate loaded oleic acid vesicles could be used effectively in the treatment of cutaneous candidiasis with minimization of side effects of econazole nitrate with increased therapeutic efficacy.