Microemulsion containing triamcinolone acetonide for buccal administration

Permeability of triamcinolone acetonide, released from mucoadhesive films, through a buccal mucosa-mimetic barrier: Permeapad™

OBJECTIVES

The permeability of triamcinolone acetonide (TA), from bilayer mucoadhesive buccal films, through a biomimetic membrane, Permeapad™, was investigated employing Franz diffusion cell. The delivery systems composition and ethyl cellulose (EC) backing layer, on drug permeability, were assessed.

METHODS

Three TA-loaded films were tested; hydroxypropyl methylcellulose (HPMC K4M; bilayer [F1] and monolayer), HPMC K4M/Polyvinylpyrrolidone (PVP): 90/10 [F2], and HPMC K15M film [F3]. All films contained propylene glycol (PG-plasticiser). TA solution alone was used as a control. TA permeability via a Permeapad™ barrier, simulating buccal mucosa, was assessed over 8 h using a Franz diffusion cell. TA permeated into the receptor compartment, released in the donor compartment, and located on/within the Permeapad™ barrier were analysed using UV-spectrophotometer.

RESULTS

45.7 % drug retention within the Permeapad™ barrier was delivered from F1 (highest). F1, F2, and F3 significantly improved the TA's permeability through Permeapad™, compared to TA solution alone (e.g., 8.5 % TA-solution, 21.5 %-F1), attributed to the synergy effect of HPMC and propylene glycol acting as penetration enhancers. F1 displayed a significant increase in drug permeability (receptor compartment; 21.5 %) compared to F3 (17.0 %). PVP significantly enhanced drug permeability (27.5 %). Impermeable EC backing layer controlled unidirectional drug release and reduced drug loss into the donor compartment (e.g., ∼28 % for monolayer film to ∼10 % for bilayer film, F1).

SIGNIFICANCE

The mucoadhesive films demonstrated improved TA permeability via Permeapad™. The findings suggest that these bilayer mucoadhesive films, particularly F1, hold promise for the effective topical treatment of oral mucosa disorders, such as recurrent aphthous stomatitis and oral lichen planus.

Emerging polymeric materials for treatment of oral diseases: design strategy towards a unique oral environment

Oral diseases are prevalent but challenging diseases owing to the highly movable and wet, microbial and inflammatory environment. Polymeric materials are regarded as one of the most promising biomaterials due to their good compatibility, facile preparation, and flexible design to obtain multifunctionality. Therefore, a variety of strategies have been employed to develop materials with improved therapeutic efficacy by overcoming physicobiological barriers in oral diseases. In this review, we summarize the design strategies of polymeric biomaterials for the treatment of oral diseases. First, we present the unique oral environment including highly movable and wet, microbial and inflammatory environment, which hinders the effective treatment of oral diseases. Second, a series of strategies for designing polymeric materials towards such a unique oral environment are highlighted. For example, multifunctional polymeric materials are armed with wet-adhesive, antimicrobial, and anti-inflammatory functions through advanced chemistry and nanotechnology to effectively treat oral diseases. These are achieved by designing wet-adhesive polymers modified with hydroxy, amine, quinone, and aldehyde groups to provide strong wet-adhesion through hydrogen and covalent bonding, and electrostatic and hydrophobic interactions, by developing antimicrobial polymers including cationic polymers, antimicrobial peptides, and antibiotic-conjugated polymers, and by synthesizing anti-inflammatory polymers with phenolic hydroxy and cysteine groups that function as immunomodulators and electron donors to reactive oxygen species to reduce inflammation. Third, various delivery systems with strong wet-adhesion and enhanced mucosa and biofilm penetration capabilities, such as nanoparticles, hydrogels, patches, and microneedles, are constructed for delivery of antibiotics, immunomodulators, and antioxidants to achieve therapeutic efficacy. Finally, we provide insights into challenges and future development of polymeric materials for oral diseases with promise for clinical translation.

Formulation and evaluation of itraconazole-loaded nanoemulgel for efficient topical delivery to treat fungal infections

Aim: The clinical application of conventional oral dosage form of itraconazole is limited due to its poor bioavailability. The aim of the study was to develop nanoemulgel of Itraconazole for topical delivery. Method: Nanoemulsions were prepared, optimized and further incorporated into a gel and evaluated for homogeneity, pH, viscosity, spreadability, in vitro drug release and skin irritation studies. Results: Cumulative drug release from nanoemulsions was within the range of 37.24 to 47.63% at 10 h. Drug release % for all the nanoemulgel formulations at10 h was 32.39, 39.75 and 45.9% respectively. Nanoemulgel was non-irritant as demonstrated by skin irritation studies in animals. Conclusion: Itraconazole nanoemulgels were proved to be potential for effective topical delivery of drug with enhanced bioavailability.

Development and Characterization of New Miconazole-Based Microemulsions for Buccal Delivery by Implementing a Full Factorial Design Modeling

This research aimed to develop miconazole-based microemulsions using oleic acid as a natural lipophilic phase and a stabilizer mixture comprising Tween 20 and PEG 400 to solubilize miconazole as an antifungal agent known for its activity in oral candidiasis and to improve its bioavailability. The formulation and preparation process was combined with a mathematical approach using a 23-full factorial plan. Fluid and gel-like microemulsions were obtained and analyzed considering pH, conductivity, and refractive index, followed by extensive analyses focused on droplet size, zeta potential, rheological behavior, and goniometry. In vitro release tests were performed to assess their biopharmaceutical characteristics. Independent variables coded X1-Oleic acid (%, w/w), X2-Tween 20 (%, w/w), and X3-PEG 400 (%, w/w) were analyzed in relationship with three main outputs like mean droplet size, work of adhesion, and diffusion coefficient by combining statistical tools with response surface methodology. The microemulsion containing miconazole base-2%, oleic acid-5%, Tween 20-40%, PEG 400-20%, and water-33% exhibited a mean droplet size of 119.6 nm, a work of adhesion of 71.98 mN/m, a diffusion coefficient of 2.11·10-5 cm2/s, and together with remarked attributes of two gel-like systems formulated with higher oil concentrations, modeled the final optimization step of microemulsions as potential systems for buccal delivery.

Combination therapy using multifunctional dissolvable hyaluronic acid microneedles for oral ulcers

Oral ulcers are common in the oral mucosa. Frequent occurrences of oral ulcers commonly afflict patients, seriously impacting their daily life. Treatments with good anti-inflammatory and antibacterial properties are important for promoting the healing of oral ulcers. In this study, a multifunctional, soluble hyaluronic acid (HA) microneedle (MN) patch was prepared to promote oral ulcer healing. The tip layer of the MN patch was loaded with triamcinolone acetonide (TA) and epidermal growth factor (EGF) to inhibit inflammation and promote angiogenesis. Zeolitic imidazolate framework-8 (ZIF-8) was loaded onto the base layer of the MN patch, which effectively released Zn2+ to mediate antibacterial effects. In addition, HA exerts a protective effect on the mucous membrane. Owing to these properties, the multifunctional MN patches were found to have good anti-inflammatory, antibacterial, and tissue-healing abilities, indicating that the multifunctional MN patch design successfully promoted the healing of oral ulcers.

Microneedle patches containing mesoporous polydopamine nanoparticles loaded with triamcinolone acetonide for the treatment of oral mucositis

Oral mucositis (OM) is the most common disease of the oral mucosa, which affects people's daily production and life. Triamcinolone ointment is the common clinical drug for OM treatment. However, the hydrophobic properties of triamcinolone acetonide (TA) and the complex microenvironment of the oral cavity led to its low bioavailability and unstable therapeutic effects on ulcer wounds. Herein, dissolving microneedle patches (MNs) composed of mesoporous polydopamine nanoparticles (MPDA) loaded with TA (TA@MPDA), sodium hyaluronic acid (HA), and Bletilla striata polysaccharide (BSP) are prepared as the transmucosal delivery system. The prepared TA@MPDA-HA/BSP MNs exhibit well-arranged microarrays, high mechanical strength and fast solubility (<3 min) properties. In addition, the hybrid structure improves the biocompatibility of TA@MPDA and expedites oral ulcer healing in the SD rat model through the synergistic anti-inflammatory and pro-healing effects of microneedle ingredients (hormones, MPDA and Chinese herbs extracts), with 90% less amount of TA compared with Ning Zhi Zhu^®. TA@MPDA-HA/BSP MNs are shown to be their great potential as novel ulcer dressings for OM management.

Role of mucoadhesive agent in ocular delivery of ganciclovir microemulsion: cytotoxicity evaluation in vitro and ex vivo

PURPOSE

The aim of the present study was to investigate increase in delivery of drug upon formulation as mucoadhesive microemulsion system and further to investigate possibility of any cytotoxic effects using such formulation.

MATERIAL AND METHODS

Considering hydrophilic and small molecular nature of the drug, it was attempted to be formulated as microemulsion, by using pseudo ternary phase diagram method. Thus, three types of microemulsions were prepared; oil in water, water in oil type and chitosan-coated microemulsion. These microemulsions were characterized for several physicochemical properties like size, zeta potential, Polydispersity index, and compared for in vitro cell viability and ex vivo corneal irritation study.

RESULTS

All three microemulsions were quite stable, transparent and homogenous systems. They showed similar drug release pattern, but highest ex vivo goat corneal permeation was observed with Chitosan coated microemulsion when compared with ganciclovir solution.

CONCLUSION

All microemulsions were found to be non-irritant in in vitro cell viability assay and ex vivo corneal irritation study, indicating the potential of using such systems for delivery of drug to eye.

Development and Characterization of Nanoemulsions for Ophthalmic Applications: Role of Cationic Surfactants

The eye is a very complex organ comprising several physiological and physical barriers that compromise drug absorption into deeper layers. Nanoemulsions are promising delivery systems to be used in ocular drug delivery due to their innumerous advantages, such as high retention time onto the site of application and the modified release profile of loaded drugs, thereby contributing to increasing the bioavailability of drugs for the treatment of eye diseases, in particular those affecting the posterior segment. In this review, we address the main factors that govern the development of a suitable nanoemulsion formulation for eye administration to increase the patient’s compliance to the treatment. Appropriate lipid composition and type of surfactants (with a special emphasis on cationic compounds) are discussed, together with manufacturing techniques and characterization methods that are instrumental for the development of appropriate ophthalmic nanoemulsions.

Formulation, optimization, qualitative and quantitative analysis of new dosage form of corticosteroid

Background

The objective of the present research work is to develop the entirely new drug product formulation (Ophthalmic Suspension) which belongs to the therapeutic class of steroids drugs (Corticosteroid). There are different dosage forms of Triamcinolone acetonide to treat different systemic as well as topical diseases as per patient symptomatic conditions. Due to non-availability of this active drug (Triamcinolone acetonide) ophthalmic dosage form in the national and international market research work is carried out to enter in this dosage form.

Results

In the formulation design and development, different inactive like polysorbate 30 mg/mL, PEG-12 glyceryl dimyristate 70 mg/mL, ethyl alcohol 10 µL/mL, citric acid 1 mg/mL, sodium citrate 3.5–4.0 mg/mL, BKC 0.15 mg/mL and water for injection have been used at different stages in different proportions during the manufacturing procedure. Gradient HPLC, C18 column, 5 µm, 100 A, 3.9 mm × 300 mm, detector UV/Vis @ 254 nm, column oven, auto-sampler, degasser, is used and this analytical testing method is validated to obtain the accurate results. The excipients play different roles including solvent, antioxidant, solubilizer, emulsifier, antibacterial, preservative, anticoagulant, antimicrobial agent, surfactant and buffers in the stability of active drug for its excellent therapeutic output results. Correlation coefficient factor is greater than 0.999 which indicates that the method has good linearity at proposed concentration against triamcinolone acetonide.

Conclusions

Excellent physical and chemical properties like physical appearance, pH, specific gravity, viscosity, re-suspendability, sedimentation volume is accomplished to meet the requirements of the eye treatment products. On the basis of experimental results achieved during validation process, it can be assumed that the current analysis method is more accurate, precise, specific, linear and consistency indicating in the range of 70 to 130% of the analyte concentration. From the physical, chemical behaviors and chemical assay of the newly developed drug formulation of corticosteroid (triamcinolone acetonide) it is concluded that it can be probably put for further clinical trial in different phases for human use.

Development of Triamcinolone Acetonide-Loaded Microemulsion as a Prospective Ophthalmic Delivery System for Treatment of Uveitis: In Vitro and In Vivo Evaluation

Treatment of uveitis (i.e., inflammation of the uvea) is challenging due to lack of convenient ophthalmic dosage forms. This work is aimed to determine the efficiency of triamcinolone acetonide (TA)-loaded microemulsion as an ophthalmic delivery system for the treatment of uveitis. Water titration method was used to construct different pseudo-ternary phase diagrams. Twelve microemulsion formulations were prepared using oleic acid, Cremophor EL, and propylene glycol. Among all tested formulations, Formulation F3, composed of oil: surfactant-co-surfactant (1:1): water (15:35:50% w/w, respectively), was found to be stable and showed acceptable pH, viscosity, conductivity, droplet size (211 ± 1.4 nm), and zeta potential (−25 ± 1.7 mV) and almost complete in vitro drug release within 24 h. The in vivo performance of the optimized formulation was evaluated in experimentally uveitis-induced rabbit model and compared with a commercial TA suspension (i.e., Kenacort^®-A) either topically or by subconjunctival injection. Ocular inflammation was evaluated by clinical examination, white blood cell count, protein content measurement, and histopathological examination. The developed TA-loaded microemulsion showed superior therapeutic efficiency in the treatment of uveitis with high patient compliance compared to commercial suspension. Hence, it could be considered as a potential ocular treatment option in controlling of uveitis.

Biological testing of chitosan-collagen-based porous scaffolds loaded with PLGA/Triamcinolone microspheres for ameliorating endoscopic dissection-related stenosis in oesophagus

Objectives

Endoscopic submucosal dissection (ESD), a preferential approach for early oesophageal neoplasms, inevitably results in oesophageal strictures in patients. Clinical use of glucocorticoids through submucosal injection is beneficial for inhibiting oesophageal stricture following injury; however, it also has limitations, such as dose loss and perforation. Hence, alternatives to glucocorticoid therapy should be developed.

Methods

A novel porous composite scaffold, ChCo‐TAMS, composed of chitosan, collagen‐I and triamcinolone acetonide (TA) loaded into poly (lactic‐co‐glycolic) acid (PLGA) microspheres (TAMS), was successfully constructed and subjected to biological testing to ameliorate oesophageal ESD‐related stenosis.

Results

The synthesized biomaterials displayed unique properties in inhibiting the activation of macrophages, chemokine‐mediated cell recruitment and fibrogenesis of fibroblasts. Further application of the scaffolds in the rat dermal defect and porcine oesophageal ESD model showed that these novel scaffolds played a robust role in inhibiting wound contracture and oesophageal ESD strictures.

Conclusions

The developed composite scaffolds provide a promising clinical medical device for the prevention of post‐operative oesophageal stricture.

Nanosystems against candidiasis: a review of studies performed over the last two decades

The crescent number of cases of candidiasis and the increase in the number of infections developed by non-albicans species and by multi-resistant strains has taken the attention of the scientific community, which has been searching for new therapeutic alternatives. Among the alternatives found the use of nanosystems for delivery of drugs already commercialized and new biomolecules have grown, in order to increase stability, solubility, optimize efficiency and reduce adverse effects. In view of the growing number of studies involving technological alternatives for the treatment of candidiasis, the present review came with the intention of gathering studies from the last two decades that used nanotechnology for the treatment of candidiasis, as well as analysing them critically and pointing out the future perspectives for their application with this purpose. Different studies were considered for the development of this review, addressing nanosystems such as metallic nanoparticles, mesoporous silica nanoparticles, polymeric nanoparticles, liposomes, nanoemulsion, microemulsion, solid lipid nanoparticle, nanostructured lipid carrier, lipidic nanocapsules and liquid crystals; and different clinical presentations of candidiasis. As a general overview, nanotechnology has proven to be an important ally for the treatment against the diversity of candidiasis found in the clinic, whether in increasing the effectiveness of commercialized drugs and reducing their adverse effects, as well as allowing exploring more effectively properties therapeutics of new biomolecules.

Topical Triamcinolone Acetonide-Loaded Liposomes as Primary Therapy for Macular Edema Secondary to Branch Retinal Vein Occlusion: A Pilot Study

Purpose: To explore safety and therapeutic efficacy of a topical ophthalmic triamcinolone acetonide-loaded liposome formulation (TA-LF) as primary therapy in patients with macular edema (ME) secondary to branch retinal vein occlusion (BRVO). Methods: Twelve eyes of 12 patients with ME secondary to BRVO were exposed to a topical instillation of 1 drop of TA-LF (TA 0.2%) 6 times a day for 12 weeks to evaluate safety and efficacy. Best corrected visual acuity (BCVA) intraocular pressure (IOP), slit lamp examination, and central foveal thickness (CFT) were analyzed at every visit. In addition, the morphology of TA-LF was analyzed using scanning electron microscopy (SEM) and transmission electron microscopy (TEM). Results: Patients presented a significant improvement of BCVA and CFT without significant IOP modification (P = 0.94). Treated eyes showed BCVA improvement from 40 ± 12.05 to 64.83 ± 15.97 letters and CFT reduction from 682.91 ± 278.60 to 271.58 ± 57.66 μm after 12 weeks of TA-LF therapy (P < 0.001). No adverse events, including IOP rising, were registered. SEM analysis of liposomal formulations showed that liposome (LP) size depends on its concentration. As the concentration of TA increased, the average size of LPs and the number of larger particles increased as well. TEM study displayed that LP formulation efficiently solubilizes TA crystals in nanoparticles and encapsulates them. Conclusion: LPs can function as nanocarriers of TA and they could be used as topical ophthalmic primary therapy instead of intravitreal drugs in patients with ME secondary to BRVO.

PEGylated microemulsion for dexamethasone delivery to posterior segment of eye

Dexamethasone (Dex) is one of the most commonly used anti-vascular endothelial growth factor (anti-VEGF) drugs being used in ocular diseases whether it is associated with anterior segment or posterior segment. For diseases of posterior segment of eye, Dex is delivered as intravitreal implant but the route used for the same is very invasive and poses several hazards on long term use. Thus, topical formulation with ability to outreach retina from ocular surface was intended. Thus, polyethylene glycolylated (PEGylated) microemulsion (ME) was attempted as it can cross the membranous barrier of eye (cornea, conjunctiva, and sclera) and remain afloat in fluidic barrier (aqueous humor, choroid, etc.) as well. Present investigation involved development of Dex-loaded PEGylated ME which was stable, non-toxic to ocular surface, capable to cross cornea and enhanced residence as well as availability of loaded drug in retina. The developed PEGylated ME had physicochemical properties like size (15.98 ± 3.05 nm), polydispersity index (0.25 ± 0.04), zeta potential (-0.04 ± 0.47 mV), percentage transmittance (99.84 ± 1.17%), and drug content (99.32 ± 3.21%). It showed sustained Dex release in in vitro conditions. It also displayed efficiency in enhancing retention of drugs in retina in in vivo pharmacokinetic study on Sprague-Dawley rats. PEGylated ME can retain the drug in retina of rats longer than simple eye drop solution via topical ocular route.

Investigation of a Microemulsion Containing Clotrimazole and Itraconazole for Transdermal Delivery for the Treatment of Sporotrichosis

The aim of this study was to develop a microemulsion (ME) formulation containing an association of itraconazole (ITC) and clotrimazole (CLT) as a transdermal delivery system for the treatment of sporotrichosis. Pseudoternary phase diagrams were constructed to optimize the ME formulation. The ME formulation selected contained 1% (w/w) ITC and 1% (w/w) CLT and was composed of 23.07% Tween® 60 (surfactant), 23.07% propylene glycol (cosurfactant/cosolvent), 30.77% benzyl alcohol (oil), and 21.09% water. The ITC/CLT-loaded ME (ITC/CLT-ME) had a droplet size value of 217 ± 0.9 nm, with a polydispersity index of 0.5 ± 0.1. Permeation experiments on pig ear skin were conducted for ITC/CLT-ME, and the results indicated that the drug permeation performance was influenced by CLT, indicating that CLT acts as a promoter enhancer. In the in vitro antifungal activity assay using Sporothrix brasiliensis yeast, the inhibition halo produced by ITC/CLT-ME exhibited a mean diameter of 43.67 ± 2.31 mm. The ITC/CLT-ME formulation did not cause skin irritation in mice. The results suggest that ITC/CLT-ME is a promising tool for the transdermal treatment of sporotrichosis.

Triamcinolone acetonide-loaded PLA/PEG-PDL microparticles for effective intra-articular delivery: synthesis, optimization, in vitro and in vivo evaluation

Nowadays the use of sustainable polymers as poly-lactic acid (PLA) and poly-δ-decalactone (PDL) in drug delivery is advantageous compared to polymers derived from fossil fuels. The present work aimed to produce microparticles (MPs) derived from novel sustainable polymers, loaded with triamcinolone acetonide (TA) for treatment of rheumatoid arthritis via intra-articular (IA) delivery. PDL was synthesized from green δ-decalactone monomers and co-polymerized with methoxy-polyethylene glycol (mPEG) forming PEG-PDL with different molecular weights. The Hansen's solubility parameters were applied to select the most compatible polymer with the drug. An o/w emulsion/solvent evaporation technique was used for MPs fabrication, using 3 [3] full factorial design. Selection of the optimized MPs was performed using Expert Design® software's desirability function. The optimized formulations were characterized using scanning electron microscope, powder X-ray diffraction, differential scanning calorimetry, infrared spectroscopy and in vitro release studies. The inhibition percents of inflammation and histopathological studies were assessed in complete Freund's adjuvant-induced rats' knee joints evaluating the effect of IA injections of selected MPs compared to the free drug suspension. Solubility studies revealed high compatibility and miscibility between TA and PEG-PDL₁₇₀₀, which was blended with PLA for convenient MPs formation. The in vitro characterization studies confirmed the formation of drug-copolymer co-crystals. The in vivo studies ensured the superiority of the newly designed composite MPs in inflammation suppression, compared to the free drug suspension and PLA MPs as well. The present study proved the advantage of using sustainable polymers in a novel combination for effective drug delivery and suggesting its usefulness in designing versatile platforms for therapeutic applications.

Development of a Method for the Quantification of Clotrimazole and Itraconazole and Study of Their Stability in a New Microemulsion for the Treatment of Sporotrichosis

Sporotrichosis occurs worldwide and is caused by the fungus Sporothrix brasiliensis. This agent has a high zoonotic potential and is transmitted mainly by bites and scratches from infected felines. A new association between the drugs clotrimazole and itraconazole is shown to be effective against S. brasiliensis yeasts. This association was formulated as a microemulsion containing benzyl alcohol as oil, Tween^® 60 and propylene glycol as surfactant and cosurfactant, respectively, and water. Initially, the compatibility between clotrimazole and itraconazole was studied using differential scanning calorimetry (DSC), thermogravimetric analysis (TG), Fourier transform infrared spectroscopy (FTIR), and X-ray powder diffraction (PXRD). Additionally, a simple and efficient analytical HPLC method was developed to simultaneously determine the concentration of clotrimazole and itraconazole in the novel microemulsion. The developed method proved to be efficient, robust, and reproducible for both components of the microemulsion. We also performed an accelerated stability study of this formulation, and the developed analytical method was applied to monitor the content of active ingredients. Interestingly, these investigations led to the detection of a known clotrimazole degradation product whose structure was confirmed using NMR and HRMS, as well as a possible interaction between itraconazole and benzyl alcohol.

Design and Development of Lidocaine Microemulsions for Transdermal Delivery

Topical administration is a preferable choice for local anesthetic delivery. Microemulsions have shown great effectiveness for transdermal transport of lidocaine. However, fabrication of microemulsions containing highly concentrated lidocaine (10%) to provide an extended local anesthetic effect is still a challenge. This study investigated the feasibility of using microemulsions for transdermal delivery of a high dosage of lidocaine (10%). At first, eutectic mixtures by kneading lidocaine with thymol were tailored to form a lipophilic solution, then the mixtures were readily incorporated into the oil phase of microemulsions after addition of proper surfactants and cosurfactants. The physicochemical properties, the skin permeation, local anesthetic efficacy, and the irritation experiment of the developed microemulsions were evaluated. The optimum composition was as follows: 12% of ethyl oleate as oil phase, 28% of the mixed surfactant, and cosurfactant (polyoxyl 15 hydroxystearate and ethanol) and 60% of the aqueous phase. The average particle size was about 13 nm. The transmission electron microscope (TEM) studies revealed almost homogeneous spherical globules without aggregation. The Fourier-transform infrared spectroscopy (FTIR) results highlighted the drugs homogeneously dispersed in the microemulsions. In vitro skin permeation and in vivo anesthesia effect evaluation indicated that microemulsions can enhance and extend the anesthetic effect of lidocaine. The irritable results indicated that the microemulsions had the better biocompatibility and the negligible influence on the dermal. Therefore, incorporating the eutectic mixtures into microemulsions could be proposed as an attractive choice and a promising transdermal delivery strategy for the future topical anesthetic therapy.