Microemulsion-based media as novel drug delivery systems

Date seed extract-loaded oil-in-water nanoemulsion: Development, characterization, and antioxidant activity as a delivery model for rheumatoid arthritis

Rheumatoid arthritis is an inflammatory disorder, affecting around 1% of the world population. Antioxidant activity plays important role to overcome the inflammation associated with arthritis. Phoenix dactylifera (date) seeds, generally considered as a waste product or utilized as food for domestic farm animals, have been used as a source of antioxidants at different disease conditions. The aim of the present study was to enhance the release of date seed extract in order to achieve high antioxidant activity. Nanoemulsion of methanolic extract of date seed was prepared by aqueous titration method. The selected formulations were exposed to thermodynamic stability and dispersibility tests. The optimized nanoemulsions were evaluated on the basis of droplet size (23.14 ± 0.055nm), polydispersity index (0.166 ± 0.124), percent transmittance (99.12 ± 0.0163), refractive index (1.36 ± 0.046), viscosity (cP) (12.30 ± 0.75), conductivity (µS/cm) (347.46 ± 1.10), and drug content (%) (99.67 ± 0.11). The in vitro release studies revealed that final optimized formulation has cumulative release of drug (57.51% ± 2.65%), which was more significantly greater as compared to drug suspension (26.44% ± 1.15%). Further in vitro antioxidant activity studies revealed that the developed methanolic extract of date seed-loaded nanoemulsion has more antioxidant potential when compared with methanolic extract.

Enhanced Lymphatic Delivery of Methotrexate Using W/O/W Nanoemulsion: In Vitro Characterization and Pharmacokinetic Study

Methotrexate, which is widely used in the treatment of cancer and immune-related diseases, has limitations in use because of its low bioavailability, short half-life, and tissue toxicity. Thus, in this study, a nano-sized water-in-oil-in-water (W/O/W) double emulsion containing methotrexate was prepared to enhance its lymphatic delivery and bioavailability. Based on the results from solubility testing and a pseudo-ternary diagram study, olive oil as the oil, Labrasol as a surfactant, and ethanol as a co-surfactant, were selected as the optimal components for the nanoemulsion. The prepared nanoemulsion was evaluated for size, zeta potential, encapsulation efficiency, pH, morphology, and in vitro release profiles. Furthermore, pharmacokinetics and lymphatic targeting efficiency were assessed after oral and intravenous administration of methotrexate-loaded nanoemulsion to rats. Mean droplet size, zeta potential, encapsulation efficiency, and pH of formulated nanoemulsion were 173.77 ± 5.76 nm, -35.63 ± 0.78 mV, 90.37 ± 0.96%, and 4.07 ± 0.03, respectively. In vitro release profile of the formulation indicated a higher dissolution and faster rate of methotrexate than that of free drug. The prepared nanoemulsion showed significant increases in maximum plasma concentration, area under the plasma concentration-time curve, half-life, oral bioavailability, and lymphatic targeting efficiency in both oral and intravenous administration. Therefore, our research proposes a methotrexate-loaded nanoemulsion as a good candidate for enhancing targeted lymphatic delivery of methotrexate.

Preparation and Characterization of Microemulsions Based on Antarctic Krill Oil

Antarctic krill oil is high in nutritional value and has biological functions like anti-inflammation and hypolipidemic effects. But it has and unpleasant smell, and unsaturated fatty acids are prone to oxidative deterioration. Its high viscosity and low solubility in water make it difficult for processing. Microemulsion can be a new promising route for development of krill oil product. We determined a formula of krill oil-in-water microemulsion with krill oil: isopropyl myristate = 1:3 as oil phase, Tween 80:Span 80 = 8:2 as surfactant, ethanol as co-surfactant and the mass ratio of surfactant to co-surfactant of 3:1. After screening the formula, we researched several characteristics of the prepared oil-in-water microemulsion, including electrical conductivity, microstructure by transmission electron microscope and cryogenic transmission electron microscope, droplet size analysis, rheological properties, thermal behavior by differential scanning calorimeter and stability against pH, salinity, and storage time.

Isotretinoin and α-tocopherol acetate-loaded solid lipid nanoparticle topical gel for the treatment of acne

AIMS

This study was aimed to develop Isotretinoin (ITN) and α-tocopherol acetate (α-TA) loaded solid lipid nanoparticle topical gel for better skin sensitivity and potentiation of efficacy.

METHODS

ITN and α-TA-loaded solid lipid nanoparticles (AE-SLN) were prepared by microemulsion method with glyceryl mono-stearate as lipid and tween 80: butanol as surfactant_mix and characterised. AE-SLN gel was evaluated for physicochemical characteristics, drug release, skin irritation and anti-acne activity in rats.

RESULTS

AE-SLNs had mean particle size of 193.4 nm (zeta-potential -29 mV) and entrapment efficiency of 84%w/w for ITN and 77.4%w/w for α-TA. AE-SLN gel showed sustained drug release for 24 h with a final cumulative release of 95.8% w/w and 89.1%w/w for ITN and α-TA. AE-SLN gel showed no erythema or edoema in rabbits and potent efficacy in rat model of acne.

CONCLUSION

In conclusion, AE-SLN gel has the potential to use as a non-irritant topical formulation for the treatment of acne.

Novel nanoemulsion gel containing triple natural bio-actives combination of curcumin, thymoquinone, and resveratrol improves psoriasis therapy: in vitro and in vivo studies

Curcumin, resveratrol, and thymoquinone are the potential natural bio-actives reported with good anti-psoriatic activity. However, poor aqueous solubility and limited skin permeation of these natural bio-actives hinder their effective delivery and potential therapeutic outcome. In this regard, current research work focuses on the design and optimization of nanoemulsion (NE) gel formulation for the concurrent delivery of these three drugs. The NE system is consisting of oleic acid as oil phase, Tween 20 as surfactant, and PEG 200 as co-surfactant. The optimized formulation exhibited the droplet size 76.20 ± 1.67 nm, PDI of 0.12 ± 0.05, RI of 1.403 ± 0.007, and viscosity of 137.9 ± 4.07 mp. Carbopol 940 (0.5% w/v) was used as the gelling agent to prepare the NE gel which exhibited a good texture profile. The optimized formulation exhibited a higher % of growth inhibition on A-431 cells and demonstrated good anti-angiogenic activity in the HET-CAM test. Finally, in vivo studies in Balb/c mice model showed improved anti-psoriatic conditions which indicated that the triple natural bio-actives combination in nanoemulgel formulation is effective in the management of psoriasis.

Alginate-based drug oral targeting using bio-micro/nano encapsulation technologies

INTRODUCTION

Oral delivery is the most common administrated drug delivery path. However, oral administration of lipophilic drugs has some limitations: they have poor dose-response due to low and varied dissolution kinetics and oral bioavailability with sub-optimal dissolution within the aqueous gastrointestinal microenvironment. Therefore, there is a need for robust formulating methods that protect the drug until it reaches to its optimum absorption site, allowing its optimum pharmacological effects via increasing its intestinal permeation and bioavailability.

AREA COVERED

Herein, we provide insights on orally administered lipophilic drug delivery systems. The detailed description of the obstacles associated with the oral bioavailability of lipophilic drugs are also discussed. Following this, techniques to overcome these obstacles with much emphasis on optimal safety and efficacy are addressed. Newly designed ionic vibrational jet flow encapsulation technology has enormous growth in lipophilic drug delivery systems, which is discussed thereafter.

EXPERT OPINION

Researchers have shown interest in drug's encapsulation. A combination of drug-bile acid and microencapsulation methods can be one promising strategy to improve the oral delivery of lipophilic drugs. However, the most critical aspect of this approach is the selection of bile acids, polymer, and encapsulation technology.

Topical Ocular Delivery of Nanocarriers: A Feasible Choice for Glaucoma Management

Topical ocular delivery is an acceptable and familiar approach for the treatment of common ocular diseases. Novel strategies for the treatment of inherited eye diseases include new pharmacologic agents, gene therapy and genome editing, which lead to the expansion of new management options for eye disorders. The topical ocular delivery of nanocarriers is a technique, which has the potential to facilitate novel treatments. Nanocarrier- based strategies have proven effective for site-targeted delivery. This review summarizes recent development in the area of topical delivery of different nanocarriers (Polymer, Vesicular and dispersed systems) for the management of glaucoma, a group of ocular disorders characterized by progressive and accelerated degeneration of the axons of retinal ganglion cells, which make up the optic nerve. Unique cellular targets for glaucoma treatment, primarily the trabecular meshwork of the anterior segment of the eye, make glaucoma facilitated by the use of nanocarriers an ideal disorder for novel molecular therapies.

Development and Evaluation of Cucurbitacin B Microemulsion: the Effect of Oil Phase and Aqueous Phase on Drug Percutaneous Absorption Based on ATR-FTIR Spectroscopy and Molecular Modeling

The present study aimed to develop a cucurbitacin B microemulsion (CuB-ME) and investigate the mechanism of the enhanced drug skin absorption at the molecular level. Firstly, the pseudo-ternary phase diagrams were developed to evaluate the effect of composition on microemulsion properties systematically. The formulation composition types and ratios of oil phase, surfactant, co-surfactant, and aqueous phase were optimized by an in vitro skin permeation experiment, and the optimized formula was confirmed with the pharmacodynamics study. Furthermore, the molecular mechanism of enhanced skin permeation was investigated using ATR-FTIR and molecular modeling. As a result, the optimized CuB-ME formulation was composed of Azone:Tween 80:ethanol:water = 2.5:16.9:5.6:75.0 (w/w/w/w). The oil phase improved skin permeation by disordering the stratum corneum intercellular liquid, while the aqueous phase impacted the particle size of the microemulsion and permeability coefficient of the drug. Besides, the hydration state of skin lipid also enhanced drug permeation by the interaction of water and the polar head of ceramide. The in vitro skin permeation amount was 45.47 ± 10.39 μg/cm², and no significant skin irritation was observed. The pharmacodynamics study demonstrated that CuB-ME had a significant therapeutic effect on the animal tumor model. In conclusion, the CuB-ME was developed successfully and the effect of the oil phase and aqueous phase on drug skin permeation was clarified at the molecular level.

Microemulsion systems to enhance the transdermal permeation of ivermectin in dogs: A preliminary in vitro study

This study aims to evaluate the influence of the phase behavior of microemulsions in the transdermal administration ("spot-on") of ivermectin, an antiparasitic drug widely used in the treatment of endoparasites and ectoparasites in dogs. In this regard, pseudoternary phase diagrams composed of water (aqueous phase), isopropyl myristate (oil phase), tween 80 (surfactant) and labrasol (cosurfactant) were obtained in a different surfactant: cosurfactant (S:CS) ratios. S:CS in 1:3 ratio presented a larger region of microemulsion formation and three microemulsions were selected from it and characterized. Subsequently, in vitro permeation and retention studies were conducted using canine skin as membrane. SAXS, rheology and conductivity data were employed to confirm the phase behavior of the microemulsions (w/o, bicontinuous or o/w). The cutaneous permeation and retention tests showed that the w/o microemulsion, followed by bicontinuous microemulsion, resulted in a higher amount of drug permeated through canine skin, suggesting better transdermal permeation. On the other hand, o/w microemulsion resulted in a higher amount of drug accumulated into the skin, suggesting better topical activity. Thus, it can be concluded that phase behavior of microemulsions influenced the drug permeation in the canine skin differently from other animal models. Microemulsions, especially w/o and bicontinuous, can be promising vehicles regarding the transdermal delivery of ivermectin.

Improved hepatoprotective activity of Beta vulgaris L. leaf extract loaded self-nanoemulsifying drug delivery system (SNEDDS): in vitro and in vivo evaluation

OBJECTIVE

Beta vulgaris L. (beetroot) is a vegetable plant rich in phytochemical compounds such as phenolic acids, carotenoids and flavonoids. The objective of the current study is the development and optimization of self-nanoemulsifying drug delivery systems (SNEDDSs) to enhance the hepatoprotective activity of beet leaf (BL) extract.

METHODS

Total flavonoids content was estimated in the BL extract and its solubility was evaluated in various vehicles to select proper component combinations. Pseudo-ternary phase diagrams were constructed employing olive, linseed, castor and sesame oils (oil phase), Tween^® 20 (Tw20) and Tween^® 80 (Tw80) (surfactants (SAs)) as well as dimethyl sulfoxide (DMSO) and propylene glycol (PG) (co-surfactants (Co-SAs)). Optimization of formulations from the phase diagrams took place through testing their thermodynamic stability, dispersibility and robustness to dilution.

RESULTS

Four optimized BL-SNEDDS formulations, comprising linseed oil or olive oil, Tw80 and DMSO at two SA/Co-SA ratios (2:1 or 3:1) were chosen. They exhibited high cloud point and percentage transmittance values with spherical morphology of mean droplet sizes ranging from 14.67 to 16.06 nm and monodisperse distribution with negatively charged zeta potential < -9.51 mV. The in vitro release profiles of the optimized formulations in pH 1.2 and 6.8 were nearly similar, with a non-Fickian release mechanism. In vivo evaluation of BL-SNEDDSs hepatoprotective activity in a thioacetamide-induced hepatotoxicity rat model depicted promoted liver functions, inflammatory markers and histopathological findings, most prominently in the group treated by F7.

CONCLUSION

The results indicate that SNEDDS, as a nanocarrier system, has potential to improve the hepatoprotective activity of the BL extract.

Microemulsion Microstructure(s): A Tutorial Review

Microemulsions are thermodynamically stable, transparent, isotropic single-phase mixtures of two immiscible liquids stabilized by surfactants (and possibly other compounds). The assortment of very different microstructures behind such a univocal macroscopic definition is presented together with the experimental approaches to their determination. This tutorial review includes a necessary overview of the microemulsion phase behavior including the effect of temperature and salinity and of the features of living polymerlike micelles and living networks. Once these key learning points have been acquired, the different theoretical models proposed to rationalize the microemulsion microstructures are reviewed. The focus is on the use of these models as a rationale for the formulation of microemulsions with suitable features. Finally, current achievements and challenges of the use of microemulsions are reviewed.

Design, Optimization, Manufacture and Characterization of Efavirenz-Loaded Flaxseed Oil Nanoemulsions

The formation, manufacture and characterization of low energy water-in-oil (w/o) nanoemulsions prepared using cold pressed flaxseed oil containing efavirenz was investigated. Pseudo-ternary phase diagrams were constructed to identify the nanoemulsion region(s). Other potential lipid-based drug delivery phases containing flaxseed oil with 1:1 m/m surfactant mixture of Tween® 80, Span® 20 and different amounts of ethanol were tested to characterize the impact of surfactant mixture on emulsion formation. Flaxseed oil was used as the oil phase as efavirenz exhibited high solubility in the vehicle when compared to other vegetable oils tested. Optimization of surfactant mixtures was undertaken using design of experiments, specifically a D-optimal design with the flaxseed oil content set at 10% m/m. Two solutions from the desired optimization function were produced based on desirability and five nanoemulsion formulations were produced and characterized in terms of in vitro release of efavirenz, physical and chemical stability. Metastable nanoemulsions containing 10% m/m flaxseed oil were successfully manufactured and significant isotropic gel (semisolid) and o/w emulsions were observed during phase behavior studies. Droplet sizes ranged between 156 and 225 nm, zeta potential between -24 and -41 mV and all formulations were found to be monodisperse with polydispersity indices ≤ 0.487.

In Silico studies of novel Sildenafil self-emulsifying drug delivery system absorption improvement for pulmonary arterial hypertension

Sildenafil is a potent selective inhibitor of phosphosdiesterase-5 previously used in erectile dysfunction and subsequently approved in 2005 for pulmonary arterial hypertension treatment. Since oral administration of sildenafil shows pharmacokinetic problems with mean absolute bioavailability of 41%, the goal of this work was to develop a novel sildenafil self-emulsifying drug delivery system (SEDDS) for oral absorption improvement and management of dosage. One pharmaceutical solution and four SEDDS containing sildenafil were successfully obtained and SEDDS formed O/W nanoemulsion with droplet size less than 300 nm. The stability studies evidenced that the SEDDS containing 3.3% w/w of sildenafil yielded the best results. The safety of 2-pyrrolidone/isobutanol in oral formulations was assessed in mice and no lethality was achieved in the placebo groups with LD50 of 490 mg/Kg for SEDDS II-3.3, suggesting it as a safe excipient for humans. Therewithal, in silico studies using PBPK models provided the pharmacokinetic profile of sildenafil SEDDS. Subsequently, in silico evaluation indicated that the sildenafil SEDDS droplet size influenced its bioavailability, enhancing absorption, assuring a good pharmacokinetic profile. These findings suggest that the formulations developed here presented the potential to enhance drug oral absorption with the possibility to control drug dosage as they are liquid pharmaceutical formulations.

Enhancement in brain uptake of vitamin D3 nanoemulsion for treatment of cerebral ischemia: formulation, gamma scintigraphy and efficacy study in transient middle cerebral artery occlusion rat models

AIM

For the treatment of cerebral ischaemia, vitamin-D₃ loaded nanoemulsions were developed.

METHOD

Tween 20 and polyethylene glycol were chosen as surfactant/co-surfactant, while oleic acid as the oil phase. The formulation was characterised for various in-vitro parameters. Targeting efficiency was investigated through radiometry, gamma scintigraphy and efficacy was studied in transient middle cerebral artery occlusion (MCAo) rat model.

RESULT

Vitamin D₃-nanoemulsion showed a mean size range of 49.29 ± 10.28 nm with polydispersity index 0.17 ± 0.04 and zeta potential 13.77 mV. The formulation was found stable during thermodynamic stability study and permeated within 180 min through sheep nasal mucosa (permeation coefficient 7.873 ± 0.884 cm/h). Gamma scintigraphy and radiometry assay confirmed better percentage deposition (2.53 ± 0.17%) of ^99mTc-vitamin D₃-nanoemulsion through nasal route compared to IV administered ^99mTc-vitamin D₃ solution (0.79 ± 0.03%). Magnetic Resonance Imaging (MRI) of the ischaemic model confirmed better efficacy of vitamin D₃-nanoemulsion.

CONCLUSION

This work demonstrated better permeation, deposition, and efficacy of vitaminD₃-nanoemulsion through the intranasal route.

Cosolvents in Self-Emulsifying Drug Delivery Systems (SEDDS): Do They Really Solve Our Solubility Problems?

The aim of this study was to investigate the fate and the impact of cosolvents in self-emulsifying drug delivery systems (SEDDS). Three different SEDDS comprising the cosolvents DMSO (F_D), ethanol (F_E), and benzyl alcohol (F_BA) as well as the corresponding formulations without these cosolvents (F_D0, F_E0, and F_BA0) were developed. Mean droplet size, polydispersity index (PDI), ζ potential, stability, and emulsification time were determined. Cosolvent release studies were performed via the dialysis membrane method and Taylor dispersion analysis (TDA). Furthermore, the impact of cosolvent utilization on payloads in SEDDS was examined using quinine as a model drug. SEDDS with and without a cosolvent showed no significant differences in droplet size, PDI, and ζ potential. The emulsification time was 3-fold (F_D0), 80-fold (F_E0), and 7-fold (F_BA0) longer due to the absence of the cosolvents. Release studies in demineralized water provided evidence for an immediate and complete release of DMSO, ethanol, and benzyl alcohol. TDA confirmed this result. Moreover, a 1.4-fold (F_D), 2.91-fold (F_E), and 2.17-fold (F_BA) improved payload of the model drug quinine in the selected SEDDS preconcentrates was observed that dropped after emulsification within 1–5 h due to drug precipitation. In parallel, the quinine concentrations decreased until reaching the same levels of the corresponding SEDDS without cosolvents. Due to the addition of hydrophilic cosolvents, the emulsifying properties of SEDDS are strongly improved. As hydrophilic cosolvents are immediately released from SEDDS during the emulsification process, however, their drug solubilizing properties in the resulting oily droplets are very limited.

Multiple Association-Dissociation Equilibria in Solutions of Amphiphilic Molecules

Amphiphilic molecules form micelles and complexes with proteins in solutions to provide unique functions, utilized in various fields of chemistry and biology, and multiple association-dissociation equilibria, governing the micellization and complexation, are key issues in these fields. The present feature article first presents an overview of theoretical backgrounds of the multiple association-dissociation equilibria in solutions of amphiphiles and then applies the theoretical results to the following four solution systems of amphiphilic molecules to understand their micellization and complexation behavior: the reverse micelle of the polymer living anion, the hydrophobe-uptake spherical micelle, the cylindrical micelle of surfactants, and the protein-surfactant complex.

Possibilities of the microemulsion use as indomethacin solubilizer and its effect on in vitro and ex vivo drug permeation from dermal gels in comparison with transcutol®

OBJECTIVE

Transcutol^® is a perfect solubilizer and an effective permeation enhancer of many active substances commonly used in cosmetics. Microemulsions due to the content of surfactant and co-surfactant could be also considered as chemical permeation enhancers that may support transdermal delivery of poorly water- soluble drugs. The purpose of this study was to investigate the effect of Transcutol^® and potential microemulsions on diffusion of poorly soluble indomethacin through an artificial membrane and excised rat skin.

METHODS

After drug solubilization in different enhancers, drug was dispersed in sodium alginate or carbopol gel used as dermal basis. For characterization of the microemulsions, the basic physico-chemical properties were determined. In vitro as well as ex vivo drug release was determined by vertical Franz cells.

RESULTS

Enhancing effect of the examined microemulsions was observed only in carbopol gel. There was an increase in cumulative drug amount released through synthetic membrane by 37.7-39.8% from the microemulsion formulation and 90.6% from Transcutol^® formulation within 6 h compared to the control samples. The differences between the permeation curves with or without the content of the enhancers were statistically significant (p < .05). Pearson correlation coefficients indicate a very high degree of dependence (r > 0.9) between in vitro and ex vivo drug release from all dermal vehicles used.

CONCLUSION

It can be stated that Transcutol^® is the best solubilizer and also penetration enhancer from the examined, and therefore it seems to be effective excipient/solubilizer in topical IND formulation.

Formulation of a Phenol-Rich Extract from Unripe Olives (Olea europaea L.) in Microemulsion to Improve Its Solubility and Intestinal Permeability

The beneficial properties of phenolic compounds from Olea europaea L. are well-known. An olive extract (OE) was prepared from unripe olives (Moraiolo cultivar). The study aimed to formulate OE into a microemulsion (ME) in oral dosage form. OE was extracted from olives with EtOH:H₂O (80:20) and characterized by HPLC-DAD. ME composition was stated by a solubility and pseudo-ternary diagram. The ME was chemically and physically characterized, and its stability at 4 °C was analyzed for three months. The ability of the formulation to ameliorate the solubility and the intestinal permeability of OE was evaluated by a Parallel Artificial Membrane Permeability Assay (PAMPA) assay and Caco-2 cells. The total phenolic content of the extract was 39% w/w. The main constituent was oleuropein (31.0%), together with ligstroside (3.1%) and verbascoside (2.4%). The ME was prepared using Capryol 90 as the oily phase, and Cremophor EL and Transcutol (2:1) as surfactant and co-surfactant, respectively. ME droplet size was 14.03 ± 1.36 nm, PdI 0.20 ± 0.08, ζ-potential −1.16 ± 0.48. Stability of ME was confirmed for at least three months. The formulation was loaded with 35 mg/mL of OE, increasing the solubility of the extract by about four times. The enhanced permeability of OE was evaluated by PAMPA, as demonstrated by the Pe value (1.44 ± 0.83 × 10⁻⁶ cm/s for OE hydroalcoholic solution, 3.74 ± 0.34 × 10⁻⁶ cm/s for OE-ME). Caco-2 cell transport studies confirmed the same results: P_app was 16.14 ± 0.05 × 10⁻⁶ cm/s for OE solution and 26.99 ± 0.45 × 10⁻⁶ cm/s for OE-ME. ME proved to be a suitable formulation for oral delivery.

The Role of Nano-ophthalmology in Treating Dry Eye Disease

Dry eye disease (DED) is a common multifactorial disease linked to the tears/ocular surface leading to eye discomfort, ocular surface damage, and visual disturbance. Antiinflammatory agents (steroids and cyclosporine A), hormonal therapy, antibiotics, nerve growth factors, essential fatty acids are used as treatment options of DED. Current therapies attempt to reduce the ocular discomfort by producing lubrication and stimulating gland/nerve(s) associated with tear production, without providing a permanent cure for dry eye. Nanocarrier systems show a great promise to revolutionize drug delivery in DED, offering many advantages such as site specific and sustained delivery of therapeutic agents. This review presents an overview, pathophysiology, prevalence and etiology of DED, with an emphasis on preclinical and clinical studies involving the use of nanocarrier systems in treating DED. Lay Summary: Dry eye disease (DED) is a multifactorial disease associated with tear deficiency or excessive tear evaporation. There are several review articles that summarize DED, disease symptoms, causes and treatment approaches. Nanocarrier systems show a great promise to revolutionize drug delivery in DED, offering many advantages such as site specific and sustained delivery of therapeutic agents. Very few review articles summarize the findings on the use of nanotherapeutics in DED. In this review, we have exclusively discussed the preclinical and clinical studies of nanotherapeutics in DED therapy. This information will be attractive to both academic and pharmaceutical industry researchers working in DED therapeutics.

Nanoemulsion as Oral Drug Delivery - A Review

BACKGROUND

Objective: The stability and delivery of drugs remain one of the key hurdles in the present situation. The present study depends on the design of a novel nanoemulsion drugdelivery system that would encapsulate a drug and to improve drug stability. The charisma of nanotechnology is majorly due to the smallest particle size at the nanoscale.

METHODS

Nanoemulsions attention is focused on emphasizing formulation aspect, method of preparation characterization techniques, evaluation parameters and various application of the nanoemulsions, several techniques to be used for the preparation of nanoemulsions like microfluidization, high-pressure homogenization, low energy emulsification and solvent evaporation method and their parameters to be characterized.

RESULTS

The design of effective formulations for drugs is being applied to enhance the solubility and bioavailability of water-insoluble drugs. The nanosized droplets have led to considerable attraction for this formulation, for the delivery of hydrophilic as well as hydrophobic drugs as drug carriers because of their improved drug solubilization capacity, long shelf life, ease of preparation and improvement of bioavailability of drugs.

CONCLUSION

The application of these nanoformulation preparations, limitations, their advantages and disadvantages as nanoemulsions will solve the various problems that current therapeutic agents face and has opened a new scenario to formulate nanoemulsions with various therapeutic agents with heightened competence along with oral drug delivery to treat diseases in the near future.

Investigating the Potential of Transmucosal Delivery of Febuxostat from Oral Lyophilized Tablets Loaded with a Self-Nanoemulsifying Delivery System

Gout is the most familiar inflammatory arthritis condition caused by the elevation of uric acid in the bloodstream. Febuxostat (FBX) is the latest drug approved by the United States Food and Drug Administration (US FDA) for the treatment of gout and hyperuricemia. FBX is characterized by low solubility resulting in poor gastrointestinal bioavailability. This study aimed at improving the oral bioavailability of FBX by its incorporation into self-nanoemulsifying delivery systems (SNEDS) with minimum globule size and maximum stability index. The SNEDS-incorporated FBX was loaded into a carrier substrate with a large surface area and lyophilized with other excipients to produce a fluffy, porous-like structure tablet for the transmucosal delivery of FBX. The solubility of FBX was studied in various oils, surfactants, and cosurfactants. Extreme vertices design was utilized to optimize FBX-SNEDS, and subsequently loaded into lyophilized tablets along with suitable excipients. The percentages of the main tablet excipients were optimized using a Box–Behnken design to develop self-nanoemulsifying lyophilized tablets (SNELTs) with minimum disintegration time and maximum drug release. The pharmacokinetics parameters of the optimized FBX-SNELTs were tested in healthy human volunteers in comparison with the marketed FBX tablets. The results revealed that the optimized FBX-SNELTs increased the maximum plasma concentration (C_max) and decreased the time to reach C_max (T_max) with a large area under the curve (AUC) as a result of the enhanced relative oral bioavailability of 146.4%. The significant enhancement of FBX bioavailability is expected to lead to reduced side effects and frequency of administration during the treatment of gout.

Marine-Derived Surface Active Agents: Health-Promoting Properties and Blue Biotechnology-Based Applications

Surface active agents are characterized for their capacity to adsorb to fluid and solid-water interfaces. They can be classified as surfactants and emulsifiers based on their molecular weight (MW) and properties. Over the years, the chemical surfactant industry has been rapidly increasing to meet consumer demands. Consequently, such a boost has led to the search for more sustainable and biodegradable alternatives, as chemical surfactants are non-biodegradable, thus causing an adverse effect on the environment. To these ends, many microbial and/or marine-derived molecules have been shown to possess various biological properties that could allow manufacturers to make additional health-promoting claims for their products. Our aim, in this review article, is to provide up to date information of critical health-promoting properties of these molecules and their use in blue-based biotechnology (i.e., biotechnology using aquatic organisms) with a focus on food, cosmetic and pharmaceutical/biomedical applications.

Preparation, characterization, and optimization of asenapine maleate mucoadhesive nanoemulsion using Box-Behnken design: In vitro and in vivo studies for brain targeting

The tight junctions between capillary endothelial cells of the blood-brain barrier (BBB) restricts the entry of therapeutics into the brain. Potential of the intranasal delivery tool has been explored in administering the therapeutics directly to the brain, thus bypassing BBB. The objective of this study was to develop and optimize an intranasal mucoadhesive nanoemulsion (MNE) of asenapine maleate (ASP) in order to enhance the nasomucosal adhesion and direct brain targetability for improved efficacy and safety. Box-Behnken statistical design was used to recognize the crucial formulation variables influencing droplet size, size distribution and surface charge of ASP-NE. ASP-MNE was obtained by incorporating GRAS mucoadhesive polymer, Carbopol 971 in the optimized NE. Optimized ASP-MNE displayed spherical morphology with a droplet size of 21.2 ± 0.15 nm and 0.355 polydispersity index. Improved ex-vivo permeation was observed in ASP-NE and ASP-MNE, compared to the ASP-solution. Finally, the optimized formulation was found to be safe in ex-vivo ciliotoxicity study on sheep nasal mucosa. The single-dose pharmacokinetic study in male Wistar rats revealed a significant increase in concentration of ASP in the brain upon intranasal administration of ASP-MNE, with a maximum of 284.33 ± 5.5 ng/mL. The time required to reach maximum brain concentration (1 h) was reduced compared to intravenous administration of ASP-NE (3 h). Furthermore, it has been established during the course of present study, that the brain targeting capability of ASP via intranasal administration had enhanced drug-targeting efficiency and drug-targeting potential. In the animal behavioral studies, no extrapyramidal symptoms were observed after intranasal administration of ASP-MNE, while good locomotor activity and hind-limb retraction test established its antipsychotic activity in treated animals. Thus, it can be concluded that the developed intranasal ASP-MNE could be used as an effective and safe tool for brain targeting of ASP in the treatment of psychotic disorders.

Oral Administration of Artemisone for the Treatment of Schistosomiasis: Formulation Challenges and In Vivo Efficacy

Artemisone is an innovative artemisinin derivative with applications in the treatment of malaria, schistosomiasis and other diseases. However, its low aqueous solubility and tendency to degrade after solubilisation limits the translation of this drug into clinical practice. We developed a self-microemulsifying drug delivery system (SMEDDS), which is easy to produce (simple mixing) with a high drug load. In addition to known pharmaceutical excipients (Capmul MCM, Kolliphor HS15, propylene glycol), we identified Polysorb ID 46 as a beneficial new additional excipient. The physicochemical properties were characterized by dynamic light scattering, conductivity measurements, rheology and electron microscopy. High storage stability, even at 30 °C, was achieved. The orally administrated artemisone SMEDDS formulation was highly active in vivo in S. mansoni infected mice. Thorough elimination of the adult worms, their eggs and prevention of the deleterious granuloma formation in the livers of infected mice was observed even at a relatively low dose of the drug. The new formulation has a high potential to accelerate the clinical use of artemisone in schistosomiasis and malaria.

Microemulsion composed of combination of skin beneficial oils as vehicle: Development of resveratrol-loaded microemulsion based formulations for skin care applications

Microemulsion can be a potential delivery vehicle to deliver skin care actives to deep skin layer for chronic skin care benefits. On top of skin care active, microemulsion vehicle composed of multiple skin beneficial oils can deliver additional skin care efficacies. In this study, microemulsions were developed using combinations of two skin beneficial oils, tea tree oil and medium chain triglyceride instead of single oil. For that, pseudo ternary phase diagrams were constructed on these oil combinations at different ratios of surfactant/co-surfactants. Ratio of oils and surfactant/co-surfactant combinations exhibited significant impact on the microemulsion region. A few compositions were selected from the single phase microemulsion regions of these phase diagrams for the preparation of resveratrol-loaded microemulsion and microemulsion gel formulations. The particle size of the resveratrol-loaded microemulsions were <50 nm. Cryogenic scanning electron microscope image clearly showed nano-droplets dispersed in continuous phase. Both physical and chemical stability of the formulations varied depending on their compositions, such as surfactant/co-surfactant combination and % total oil. The presence of chelating agent and anti-oxidant was also crucial to stabilize the formulations. The selected formulations demonstrated good physicochemical stability at 5 °C, 25 °C, and 40 °C/75 % RH (relative humidity) stability conditions. The results further showed that the % total oil and surfactant phase composition had huge influence on resveratrol release and skin permeation patterns from the microemulsion gels. In vitro skin permeation result indicated that the microemulsion gels can help resveratrol penetration into deep skin layer. Therefore, the developed resveratrol-loaded microemulsion gels can be utilized as skin care product with multiple skin care benefits.

Salvianolic Acid B in Microemulsion Formulation Provided Sufficient Hydration for Dry Skin and Ameliorated the Severity of Imiquimod-Induced Psoriasis-Like Dermatitis in Mice

Psoriasis is a chronic inflammatory skin disorder with a pathogenesis involving the interleukin-23/interleukin-17 axis. Salvianolic acid B exerts several pharmacological effects, such as antioxidation, anti-inflammation, and antitumor effects. The anti-psoriatic effects of salvianolic acid B have not been reported. In this study, we aimed to determine the optimum vehicle for salvianolic acid B, investigate its therapeutic effect on psoriatic-like skin conditions, and explore its underlying mechanisms of action. BALB/c mice were administered topical imiquimod to induce psoriasis-like skin and were then randomly assigned to control, vehicle control, salvianolic acid B in vehicles, and 0.25% desoximetasone ointment treatment groups. Barrier function, cytokine expression, histology assessment, and disease severity were evaluated. The results showed that salvianolic acid B-containing microemulsion alleviated disease severity, reduced acanthosis, and inhibited interleukin-23/interleukin-17 (IL-23/IL-17) cytokines, epidermal proliferation, and increased skin hydration. Our study suggests that salvianolic acid B represents a possible new therapeutic drug for the treatment of psoriasis. In addition, such formulation could obtain high therapeutic efficacy in addition to providing sufficient hydration for dry skin.

Digital Proxy of a Bio-Reactor (DIYBOT) combines sensor data and data analytics to improve greywater treatment and wastewater management systems

Technologies to treat wastewater in decentralized systems are critical for sustainable development. Bioreactors are suitable for low-energy removal of inorganic and organic compounds, particularly for non-potable applications where a small footprint is required. One of the main problems associated with bioreactor use is sporadic spikes of chemical toxins, including nanoparticles. Here, we describe the development of DIYBOT (Digital Proxy of a Bio-Reactor), which enables remote monitoring of bioreactors and uses the data to inform decisions related to systems management. To test DIYBOT, a household-scale membrane aerated bioreactor with real-time water quality sensors was used to treat household greywater simulant. After reaching steady-state, silver nanoparticles (AgNP) representative of the mixture found in laundry wastewater were injected into the system to represent a chemical contamination. Measurements of carbon metabolism, effluent water quality, biofilm sloughing rate, and microbial diversity were characterized after nanoparticle exposure. Real-time sensor data were analyzed to reconstruct phase-space dynamics and extrapolate a phenomenological digital proxy to evaluate system performance. The management implication of the stable-focus dynamics, reconstructed from observed data, is that the bioreactor self-corrects in response to contamination spikes at AgNP levels below 2.0 mg/L. DIYBOT may help reduce the frequency of human-in-the-loop corrective management actions for wastewater processing.

Magnetic Nanoparticles as MRI Contrast Agents

Iron oxide nanoparticles (IONPs) have emerged as a promising alternative to conventional contrast agents (CAs) for magnetic resonance imaging (MRI). They have been extensively investigated as CAs due to their high biocompatibility and excellent magnetic properties. Furthermore, the ease of functionalization of their surfaces with different types of ligands (antibodies, peptides, sugars, etc.) opens up the possibility of carrying out molecular MRI. Thus, IONPs functionalized with epithelial growth factor receptor antibodies, short peptides, like RGD, or aptamers, among others, have been proposed for the diagnosis of various types of cancer, including breast, stomach, colon, kidney, liver or brain cancer. In addition to cancer diagnosis, different types of IONPs have been developed for other applications, such as the detection of brain inflammation or the early diagnosis of thrombosis. This review addresses key aspects in the development of IONPs for MRI applications, namely, synthesis of the inorganic core, functionalization processes to make IONPs biocompatible and also to target them to specific tissues or cells, and finally in vivo studies in animal models, with special emphasis on tumor models.

Preparation and in vitro and in vivo Study of Asiaticoside-Loaded Nanoemulsions and Nanoemulsions-Based Gels for Transdermal Delivery

Purpose

Asiaticoside (ASI), a compound of triterpene pentacyclic saponins, has apparently therapeutic efficacy on human hypertrophic scar. However, the characteristics of large molecular weight, low water solubility and poor lipophilicity do not favor the diffusion through the stratum corneum (SC). Therefore, it is expected that the development of a transdermally delivered formulation may enhance the permeability ratio (Qn) of ASI for its clinical application. In this study, we designed asiaticoside-loaded nanoemulsions (ASI-NEs) and nanoemulsions-based gels (ASI-NBGs) and studied their mechanism for transdermal delivery.

Methods

The preparation of ASI-NEs was optimized by simplex lattice design (SLD). The ex vivo transdermal penetration and the in vivo pharmacokinetics studies were studied, respectively. The skin irritation of ASI-NEs and ASI-NBGs was measured on normal and damaged skin in rabbits, and the transcutaneous mechanisms of ASI-NEs and ASI-NBGs were determined by HE stained and confocal laser scanning microscopy (CLSM).

Results

The mean particle size of ASI-NEs was 132±5.84nm. The ex vivo skin permeation study verified that the Qn of the optimized ASI-NEs and ASI-NBGs was about 13.65 times and 5.05 times higher than that of the ordinary ASI-G group. In vivo, the pharmacokinetics studies showed that ASI-NEs and ASI-NBGs reached the peak value in the skin quickly and maintained stable release for a long time with high bioavailability. ASI-NEs and ASI-NBGs were proved to be safe when applied for topical skin usage, and they could play a therapeutic role through the skin mainly by acting on the microstructure of the SC and by means of the skin adnexal pathways.

Conclusion

ASI-NEs and ASI-NBGs were effectively developed to overcome the barrier properties of the skin and show high drug penetration through the transdermal route. In addition, we found that ASI-NEs and ASI-NBGs are safe when applied through transdermal delivery system.

Design and development of a commercially viable in situ nanoemulgel for the treatment of postmenopausal osteoporosis

Aim: To investigate the potential of a thermosensitive intranasal formulation of raloxifene hydrochloride (RH) for systemic delivery with the possibility of enhanced bioavailability and anti-osteoporotic efficacy. Methods: In this work, a commercially scalable nanoemulsion in thermosensitive gel, aligned with better clinical acceptability, has been developed and evaluated. Results: A significant 7.4-fold improvement in bioavailability of RH was recorded when compared with marketed tablets. Likewise, in vivo pharmacodynamics studies suggested 162% enhanced bone density and significantly improved biochemical markers compared with per-oral marketed tablet. Conclusion: The formulation, being safe and patient compliant, successfully tuned anti-osteoporotic effects with improved therapeutic performance. Further, the work provided an exceptional lead to carry out the study in clinical settings.

Stretchable Polydimethylsiloxane Composites with Emulsified Ionic Materials and Thermochromic Applications

In this study, a new preparation method is developed to include thermochromic complex ions in polydimethylsiloxane (PDMS) as a stretchable composite. Ethylene glycol (EG) droplets down to the nanometer scale were dispersed using a reverse micelle method to form a stable suspension in PDMS precursor solution. After curing, the EG nanodroplets were well encapsulated in the cured PDMS elastomer. The EG/PDMS composite exhibited great stability after thermal heating at 100 °C for 2 hours. The deformable liquid droplets helped maintaining the composite structures under severe stretching conditions, and thus the stretched composite exhibited great transparency without any fractures or delamination. Ionic dyes, such as methylene blue and Congo red, can be added in the EG droplets to color the composite. Moreover, complex ions with thermochromic properties can also be used in the composite. Upon thermal heating, the reconfiguration of the complex ions in the liquid dispersed phase led to obvious color changes, and the color remained unchanged up to 50% tensile strain after more than 1000 stretch cycles.

Oral delivery of lycopene-loaded microemulsion for brain-targeting: preparation, characterization, pharmacokinetic evaluation and tissue distribution

Lycopene is considered as a promising neuroprotector with multiple bioactivities, while its therapeutic use in neurological disorders is restricted due to low solubility, instability and limited bioavailability. Our work aimed to develop lycopene-loaded microemulsion (LME) and investigate its potentials in improving bioavailability and brain-targeting efficiency following oral administration. The blank microemulsion (ME) excipients were selected based on orthogonal design and pseudo-ternary phase diagrams, and LME was prepared using the water titration method and characterized in terms of stability, droplet size distribution, zeta potential, shape and lycopene content. The optimized LME encompassed lycopene, (R)-(+)-limonene, Tween 80, Transcutol HP and water and lycopene content was 463.03 ± 8.96 µg/mL. This novel formulation displayed transparent appearance and satisfactory physical and chemical stabilities. It was spherical and uniform in morphology with an average droplet size of 12.61 ± 0.46 nm and a polydispersity index (PDI) of 0.086 ± 0.028. The pharmacokinetics and tissue distributions of optimized LME were evaluated in rats and mice, respectively. The pharmacokinetic study revealed a dramatic 2.10-fold enhancement of relative bioavailability with LME against the control lycopene dissolved in olive oil (LOO) dosage form in rats. Moreover, LME showed a preferential targeting distribution of lycopene toward brain in mice, with the value of drug targeting index (DTI) up to 3.45. In conclusion, the optimized LME system demonstrated excellent physicochemical properties, enhanced oral bioavailability and superior brain-targeting capability. These findings provide a basis for the applications of ME-based strategy in brain-targeted delivery via oral route, especially for poorly water-soluble drugs.

3,5,4'-Trimethoxy-trans-stilbene loaded microemulsion for cutaneous melanoma therapy by transdermal drug delivery

For therapy of skin cancer, transdermal administration has been a potential way to enhance chemotherapy. However, the drug delivery efficacy remained unsatisfactory because of the physiological barriers from the skin to the tumor, which hindered the effect of 3,5,4'-trimethoxy-trans-stilbene (BTM), a drug that has toxicity to cancer. Herein, we prepared an oil-in-water (O/W) microemulsion to load BTM (BTM-ME) for transdermal therapy of melanoma. BTM-ME was characterized by size, zeta potential, and polymer disperse index (PDI). B16F10 melanoma cell line was used for cell experiments and animal models. And cell uptake, viability assay, and flow cytometry were to test the cell internalization and the ability of BTM-ME to induce cancer cell apoptosis. Skin penetration testing was to detect its penetration efficiency to the skin. And tumor-bearing mice were used to prove the improvement of anti-cancer efficacy of BTM-ME with the combination of Taxol. BTM was successfully loaded in O/W microemulsion, with a drug loading capacity of 24.82 mg/mL. BTM-ME can penetrate the skin and increase the retention of BTM in the epidermis. And the combination of Taxol and BTM-ME effectively suppressed tumor growth and has lower toxicity to normal organs. BTM-ME provides adjuvant therapy to cutaneous melanoma and the combination of Taxol and BTM-ME has the clinical potential for skin cancer therapy. Graphical abstract.

Topical Delivery of Coenzyme Q10-Loaded Microemulsion for Skin Regeneration

The aim of this study was to develop a coenzyme Q10 (CoQ10) microemulsion system with improved solubility, penetration, and wound healing efficacy. Based on the pseudo-ternary diagram, microemulsions containing isopropyl myristate (IPM), Cremophor EL^®, and Transcutol^® HP were selected and confirmed to be nanosized (<20 nm) and thermodynamically stable based on the dilution and thermodynamic stability tests. The CoQ10-loaded microemulsion with a surfactant/co-surfactant (S/CoS) ratio of 2:1 (w/w %) demonstrated a higher permeation efficacy compared to microemulsions with S/CoS ratio of 3:1 or 4:1 (w/w %). Additionally, the CoQ10-loaded microemulsion with an S/CoS ratio of 2:1 demonstrated a relatively rapid wound healing effect in keratinocytes and fibroblasts. Overall, these data suggest that a microemulsion based on IPM, Cremophor EL^®, and Transcutol^® HP could be an effective vehicle for the topical administration of CoQ10 and could be utilized for the application of other therapeutic agents that have difficulty in penetrating the skin.

A comparative ex vivo permeation evaluation of a novel 5-Fluorocuracil nanoemulsion-gel by topically applied in the different excised rat, goat, and cow skin

AIM OF THE STUDY

5-Fluorouracil (5-FU) can't be given orally because of very low bioavailability and produces serious adverse effects. Therefore, the main objective of this research is to develop, evaluate, and comparative effects by different nanoformulations of topical application on chemoprevention of skin cancer in different types of skin.

MATERIAL AND METHODS

Castor oil (oil), Transcutol HP (surfactant), and Polyethylene glycol (PEG)-400 (co-surfactant) have taken on the basis of nonionic property and highest nanoemulsion (NE)-region. Aqueous micro titration method with ultra-sonication method (based on high energy) was used for the preparation of 5-FU-NE. Optimized-5-FU-NE was stable thermodynamically, and their characterizations was performed on the basis of globule size, zeta potential, refractive index, and viscosity. Optimized-NE has been converted into 5-FU-NE-Gel with the help of Carbopol® 934 and also performed their permeation studies in the different skins (cow, goat, and rat, ex vivo) using Logan transdermal diffusion cell (DHC-6T). Optimized-5-FU-NE and 5-FU-NE-Gel were evaluated cytotoxic studies (in vitro) on the melanoma cell lines.

RESULTS

The permeation of 5-FU from 5-FU-NE-Gel nanoformulation for rat skin model was 1.56 times higher than the 5-FU-NE and 12.51 times higher than the 5-FU-S for the cow and goat skin model. The values of steady state flux and permeability coefficient for 5-FU-NE-Gel of rat skin were higher i.e. 12.0244 ± 1.12 µgcm-2h-1 and 1.2024 ± 0.073 × 10-2 µg cm-2h-1, respectively. Optimized-5-FU-NE and 5-FU-NE-Gel nanoformulation were found to be physically stable. SK-MEL-5 cancer cells have showed the results based on cytotoxicity studies (in vitro) that 5-FU as Optimized-5-FU-NE-Gel is much more efficacious than 5-FU-NE followed by free 5-FU. Localization of 5-FU from 5-FU-NE-Gel was higher with higher permeation in rat skin.

CONCLUSION

5-FU-NE-Gel is found to be for the better to treatment of cutaneous malignancies. It can be developed 5-FU-NE-Gel could be a promising vehicle for the skin cancer chemoprevention.

Use of Nanomaterials in Food Science

The current global population is nearly 6 billion; due to this rapid population growth, there is a need to produce food in a more efficient, safe, and sustainable way, and it should be safe from the adverse effects of pathogenic organisms. A large proportion of population living in developing countries face daily food shortages as a result of environmental impacts or some other reasons like political instability, etc., while in the developed countries, food is surplus. For developing countries, the objective is to develop drought- and pest-resistant crops, with maximized yield. In developed countries, the food industry depends on consumer’s demand for fresher and healthier foodstuffs. The present chapter describes the use of nanoparticles in food science.

Topical Delivery of Meloxicam using Liposome and Microemulsion Formulation Approaches

The aim of this study is to develop, characterize and compare conventional liposome, deformable liposome (transfersome) and microemulsion formulations as potential topical delivery systems for meloxicam. Liposomes were characterized in terms of vesicle size, zeta potential and entrapment efficiency. For microemulsions, particle size, electrical conductivity and viscosity studies were performed to assess the structure of the investigated systems. An ex vivo skin permeation study has been conducted to compare these formulations. The dermal and transdermal delivery of meloxicam using these formulations can be a promising alternative to conventional oral delivery of non-steroidal anti-inflammatory drugs (NSAIDs) with enhanced local and systemic onset of action and reduced side effects.

Enhanced bioavailability and antihypertensive activity of nisoldipine loaded nanoemulsion: optimization, cytotoxicity and uptake across Caco-2 cell line, pharmacokinetic and pharmacodynamic studies

Objective: The present study explored the antihypertensive activity of nisoldipine in oil in water nanoemulsion to improve its oral bioavailability via intestinal lymphatic uptake.Methods: Nanoemulsion was prepared by ultrasonication technique using Peceol, Cremophor EL and Transcutol HP as oil, surfactant and cosurfactant respectively. Optimization was done employing 3² full factorial design. The developed formulation was assessed for in vitro,cell line, ex vivo and in vivo studies.Results: The experimental results indicated homogeneity of the nanoemulsion with globule size of 62.35 ± 2.55 nm and PDI value of 0.108 ± 0.01 with negative zeta potential (-26.2 ± 3.6 mV). Transmission electron microscopy showed spherical oil globules morphology. The in vitro diffusion study showed significant increase in drug release from NE formulations (98.51 ± 2.64%) as compared to plain drug dispersion (29.73 ± 2.15%) in 0.1 N HCl + 0.5% SLS medium. Moreover, higher quantitative and qualitative uptake of nanoemulsion via Caco-2 cells showed superior intestinal absorption and improved therapeutic activity of nisoldipine when compared to drug dispersion. Pharmacokinetic and pharmacodynamic study confirmed significantly (p ˂ 0.05) greater bioavailability and antihypertensive activity of nisoldipine nanoemulsion when compared to its dispersion. These results are visualized in abstract figure.Conclusion: Thus, prepared nanoemulsion showed potential as oral delivery system for nisoldipine with superior oral bioavailability and therapeutic efficacy over drug dispersion.

Etoricoxib-loaded bio-adhesive hybridized polylactic acid-based nanoparticles as an intra-articular injection for the treatment of osteoarthritis

Osteoarthritis is a major problem in elder people. Etoricoxib-loaded bio-adhesive hybridized nanoparticles were prepared using polylactic acid (PLA) and chitosan hydrochloride (CS-HCl) in presence of Captex®200 as a liquid oil, polyvinyl alcohol (PVA) and Tween®80 as surfactants. The study aimed to present a new intra-articular treatment of osteoarthritis with anti-inflammatory as well as bone rebuilding effects. Hybridized nanoparticles were fabricated applying the emulsion solvent evaporation technique then assessed for particle size, zeta potential, entrapment efficiency and in-vitro drug release. Furthermore, FT-IR and DSC in addition to morphological examination were done. Results revealed that the formulation composed of PLA:Captex®200 in ratio 1:2 (w/w), 1%w/v Tween®80, 0.3% w/v CS-HCl and 3%w/v PVA possessed the smallest particle size and the most sustained drug release, thus was sorted for further analyses. The selected formulation ability to interact with the negatively charged sodium fluroscein was evaluated to predict its binding with the naturally occurring hyaluronic acid in the knee joint where promising results were obtained. Results showed the cytocompatibility of the formulation when tested using MC3T3-E1 normal bone cell line, enhanced ALP activity and increased calcium ion deposition and binding. Results suggested that the presented formulation can be considered as an innovative approach for osteoarthritis.