Dry Emulsion Research Articles

Preparation and Characterization of Isradipine as Surfactant-Free Dry Emulsion

Background: Oral anticoagulation medication, warfarin, and non-vitamin K antagonist oral anticoagulants (NOAC) may require long-term use which may affect patients’ satisfaction with their treatment and their quality of life (QOL). Objective: To compare the quality of life and treatment satisfaction among groups of patients using different anticoagulant therapies (warfarin and NOAC). Methods: A cross-sectional study was performed at Ibn Al-Bitar Hospital for cardiac surgery in Baghdad in the period from December 2022 to May 2023. The study population included a convenient sample of patients receiving either warfarin or non-vitamin k antagonist oral anticoagulants treatment. The Arabic version of the short form 12 (SF-12) questionnaire and the Anti-Coagulant Treatment Satisfaction Scale (ACTS) questionnaire were used to assess the quality of life and satisfaction with treatment respectively. Results: The study included 181 patients in total. The mean physical and mental quality of life scores for study participants were 42.3±9.92 and 52.6±10.36 respectively. There was no significant difference in the QOL between patients taking warfarin and those on non-vitamin k antagonist oral anticoagulant treatment. The mean total satisfaction score was 65.4±6.73. Patients receiving non-vitamin k antagonist oral anticoagulants had significantly higher satisfaction compared to those receiving warfarin. The physical score correlated significantly with gender, educational level, employment status, number of chronic medications, and number of chronic diseases. The total satisfaction score correlated significantly with gender, number of chronic medications, number of side effects, and duration of anticoagulation. There was a significant correlation between the QOL and treatment satisfaction. Conclusion: Treatment with non-vitamin K antagonist oral anticoagulants showed comparable QOL and higher treatment satisfaction than that of warfarin. Better treatment satisfaction can improve patients’ QOL which may ultimately enhance their adherence to treatment.

A Dual Emission Fluorescence Probe Based on Silicon Nanoparticles and Rhodamine B for Ratiometric Detection of Kaempferol.

In this paper, blue fluorescent silicon nanoparticles (SiNPs) with outstanding optical properties and robust stability were synthesized by a simple one-step hydrothermal method. By introducing red emissive rhodamine B (RhB) into SiNPs solution, a dual emission nanoprobe (SiNPs@RhB) was constructed, which showed excellent pH stability, salt resistance and photobleaching resistance. The SiNPs@RhB probe could emit two peaks at 444nm and 583nm under 365nm excitation. It was found that the fluorescence intensity of the two emission peaks decreased in different degrees with the addition of different concentrations of kaempferol (Kae). According to this phenomenon, a novel ratiometric fluorescence method was established for the detection of Kae via utilizing SiNPs@RhB as nanoprobe. The detection range and limit of detection (LOD) were 0.5 ~ 150 µM and 0.24 µM, respectively. The ratiometric fluorescence method exhibited the superiority of rapid detection, excellent stability, wide linear range and high sensitivity. The detection mechanism was studied by ultraviolet visible absorption spectra, fluorescence spectra and fluorescence lifetime. Furthermore, the method was applied to the detection of Kae in real samples (kaempferia powder, sea buckthorn granules and sea buckthorn dry emulsion).

Development and Evaluation of a Dry Emulsion of Ostrich Oil as a Dietary Supplement.

This study aimed to develop a high-quality dry emulsion incorporating omega-3, 6, and 9 fatty acid-rich ostrich oil for use as a dietary supplement. Extracted from abdominal adipose tissues using a low-temperature wet rendering method, the ostrich oil exhibited antioxidant properties, favorable physicochemical properties, microbial counts, heavy metal levels, and fatty acid compositions, positioning it as a suitable candidate for an oil-in-water emulsion and subsequent formulation as a dry emulsion. Lecithin was employed as the emulsifier due to its safety and health benefits. The resulting emulsion, comprising 10% w/w lecithin and 10% w/w ostrich oil, was stable, with a droplet size of 3.93 ± 0.11 μm. This liquid emulsion underwent transformation into a dry emulsion to preserve the physicochemical stability of ostrich oil, utilizing Avicel® PH-101 or Aerosil® 200 through a granulation process. Although Aerosil® 200 exhibited superior adsorption, Avicel® PH-101 granules surpassed it in releasing the ostrich oil emulsion. Consequently, Avicel® PH-101 was selected as the preferred adsorbent for formulating the ostrich oil dry emulsion. The dry emulsion, encapsulated with a disintegration time of 3.11 ± 0.14 min for ease of swallowing, maintained microbial loads and heavy metal contents within acceptable limits. Presented as granules containing butylated hydroxytoluene, the dry emulsion showcased robust temperature stability, suggesting the potential incorporation of animal fat into dry emulsions as a promising dietary supplement.

Enhancing the Retention and Oxidative Stability of Volatile Flavors: A Novel Approach Utilizing O/W Pickering Emulsions Based on Agri-Food Byproducts and Spray-Drying.

Spray-drying is a commonly used method for producing powdered flavors, but the high temperatures involved often result in the loss of volatile molecules. To address this issue, our study focused on a novel approach: developing O/W Pickering emulsions with agri-food byproducts to encapsulate and protect D-limonene during spray-drying and storage. Emulsions formulated with lupin hull, lupin-byproduct (a water-insoluble protein-fiber byproduct derived from the production of lupin protein isolate), and camelina press-cake were subjected to spray-drying at 160 °C. The results revealed that these emulsions exhibited good stability against creaming. The characteristics of the dry emulsions (powders) were influenced by the concentration of byproducts. Quantitative analysis revealed that Pickering emulsions enhanced the retention of D-limonene during spray-drying, with the highest retention achieved using 3% lupin hull and 1% camelina press-cake. Notably, lupin-stabilized emulsions yielded powders with enhanced oxidative stability compared to those stabilized with camelina press-cake. Our findings highlight the potential of food-grade Pickering emulsions to improve the stability of volatile flavors during both processing and storage.

Micronized dry emulsion with solid nanocore: A novel strategy to incorporate a large amount of ceramides

Conventional oil-in-water or water-in-oil emulsions that serve as carriers for drugs and other hydrophobic substances eventually break down and undergo phase separation, coalescence, creaming, and/or flocculation. To overcome this issue, we fabricated dry emulsions with solid cores that can encapsulate high amount of ceramides with high hydrophobicity (logP>9) via spray drying. Based on pseudo-ternary diagrams of 50 formulations, 5 nanoemulsions with an optimum particle size (∼200 nm) and good storage stability (4 weeks) were selected and used to fabricate core-shell-type dry emulsions with ceramides (cDEs). These cDEs were microsized spheres and incorporated 15-23 % (w/w) of ceramides in emulsions. The solid-core cDEs 5 and 6 well-reconstituted in water, presented good colloidal stability with low polydispersity (PDI<0.15), and were smaller than those of DEs with liquid cores. Moreover, the selected DEs exhibited particle sizes of 4–7 μm and reconstituted to a submicron size. We believe that our cDEs could be a tool to encapsulate poorly soluble ceramides and other insoluble bioactive compounds in commercial products.

Characterization of quinoa starch nanoparticles as a stabilizer for oil in water Pickering emulsion.

Quinoa starch nanoparticles (QSNPs) prepared by nanoprecipitation had a uniform particle size of 191.20nm. QSNPs with amorphous crystalline structure had greater contact angle than QS with orthorhombic crystalline structure, which can therefore be utilized to stabilize Pickering emulsions. QSNPs-based Pickering emulsions prepared by suitable formulations (QSNPs concentration of 2.0-2.5%, oil volume fraction of 0.33-0.67) exhibited good stability against pH of 3-9 and ionic strength of 0-200mM. The oxidative stability of the emulsions increased with increasing starch concentration and ionic strength. Microstructural and rheological results indicated that the structure of the starch interfacial film and the thickening effect of the water phase affected the emulsion stability. The emulsion had excellent freeze-thaw stability and can be produced as a re-dispersible dry emulsion using the freeze-drying technique. These results implied that the QSNPs had great potential for application in the preparation of Pickering emulsions.

Artesunate Dry Emulsion Formulation Combined with Antibiotics for Treatment of Helicobacter pylori Infections: In Vitro/In Vivo Evaluation.

Helicobacter pylori is the primary pathogen responsible for causing gastroduodenal ulcers and stomach cancer. The standard treatment for H. pylori typically involves a combination of antibiotics and acid-reducing medications. However, the recurrence of ulcers is closely linked to the emergence of antibiotic resistance in H. pylori, necessitating the development of alternative drugs. This report focuses on the investigation of artesunate as a potential alternative to reduce antibiotic use and enhance effectiveness against H. pylori. Unfortunately, commercial artesunate is available in an acid form, which has poor solubility, especially in gastric acid fluid. The aim of this study is to utilize a water-soluble formulation of artesunate called dry emulsion formulation (ADEF) and combine it with amoxicillin to eradicate H. pylori. In vitro studies were conducted to evaluate the activity of ADEF against H. pylori and determine its inhibitory concentrations. In addition, pharmacokinetic parameters of orally administered ADEF and native artesunate were investigated in rats for in vivo studies. The results showed that when combined with amoxicillin and pantoprazole, ADEF exhibited effectiveness against H. pylori. It is worth noting that the solubility of ADEF in gastric acid appears to be a critical factor for achieving successful treatment. Consequently, ADEF could be considered a promising candidate for H. pylori therapy.

Enhanced Pharmacokinetics and Anti-inflammatory Activity of Curcumin Using Dry Emulsion as Drug Delivery Vehicle.

Many naturally available dietary molecules such as curcumin have not seen the market due to poor solubility, bioavailability, and photodegradability. Successful development of a lipid-based dry emulsion may overcome these issues and help in reaching the markets for natural dietary molecules such as curcumin. The current study aims to develop a dry emulsion formulation of curcumin using natural oil and evaluate its dissolution, photostability, pharmacokinetics, and anti-inflammatory activity. Dry emulsions were prepared using emu oil and corn oil as the lipid phase, Caproyl 90 and Cremophor RH 40 as surfactants, and dextrin as a hydrophilic carrier. Microscopic studies showed the formation of spherical porous particles, and solid-state characterization using differential scanning calorimetry and powder X-ray diffraction showed the conversion of curcumin to an amorphous form. About 80% drug release was observed from formulation, whereas pure drug showed only 50% drug release in 30min. Invivo pharmacokinetic studies showed fivefold improvement in the maximum concentration of curcumin in plasma (Cmax) and sevenfold improvement in the area under the concentration-timecurve of curcumin from emu oil formulation compared with pure curcumin. Significant differences were observed in the anti-inflammatory activity of curcumin dry emulsion and plain curcumin. Emu-oil-based formulations showed synergistic anti-inflammatory activity over corn-oil-based formulations with improved photostability. The present study suggests that the dry emulsion may enhance the bioavailability with synergistic anti-inflammatory activity and photostability of curcumin when given orally.

Comparison of different indirect approaches to design edible oleogels based on cellulose ethers

Growing public concern about the adverse health effects of overconsumption of saturated fat has contributed to the rising research interest in the field of using healthy oils to construct edible structured oils (oloegels) as fat-based alternatives. In this study two indirect methodologies (the emulsion template approach and the foam template approach) were investigated to prepare oleogels with hydroxypropyl methylcellulose and methylcellulose as gelling agent at three different oil concentrations. Microstructure, texture, rheology, and oil retention capacity were measured to evaluate the structural and physicochemical properties of oleogels. Results showed that the emulsion-based oleogel effectively inhibited the aggregation of droplets. The dry emulsion showed independent droplets and an oil retention capacity of 100%. In foam-type oleogels the oil retention rate was negatively correlated with the oil content. The oleogels prepared by both methods have excellent mechanical properties and gel strength, with a predominance of the elastic versus the viscous behavior. Hydroxypropyl methylcellulose and methylcellulose had different degrees of influence on the structure and mechanical properties of the two oleogels. The results of this paper provide guidance for the development and application of cellulose-based oleogels as healthy alternatives to saturated fat. • Different approaches result in different microstructure and oil retention capacity. • Oil content plays an important role in textural and rheological properties. • Oleogels present high gel strength and low dependence on frequency and temperature.

Preparation and Characterization of Nifedipine-Loaded Dry Medium Internal-Phase Emulsions (Dry MIPEs) to Improve Cellular Permeability.

A nifedipine (NP) dry emulsion was fabricated by the adsorption of medium internal-phase emulsions (MIPEs). Simple homogenizers were first used to mix conventional liquid MIPEs, and then a microfluidizer was used to reduce the resulting emulsions’ droplet sizes. The dry MIPEs (solid) were produced by adsorbing the emulsions onto solid carriers with a high surface area. The dry MIPEs were diluted in a simulated gastric fluid under gentle agitation to form emulsions. The diluted dry MIPEs were divided into three groups based on an NP content of 0.3%, 0.5%, and 0.7%, with sizes of 5026–5404 nm, 2583–3233 nm, and 1318–1618 nm in diameter, respectively. Powder X-ray diffraction (PXRD) measurements and differential scanning calorimetry (DSC) were used to characterize the physical properties of the dry MIPEs. The samples contained 0.5% or 0.7% drug, 2–4% surfactant, and 8–16% oil (5RH2/8, 7RH2/8, and 7RH4/16) and showed the characteristic peak for NP. No NP peak was observed in formulations with 0.3% NP and any oil-phase content (3RH2/8, 3RH4/16, and 3RH8/32). The formulations with 0.5% drug, 4–8% surfactant, 16–32% oil (5RH4/16 and 5RH8/32) and those with 0.7% drug, 8% surfactant, and 32% oil (7RH8/32) also did not show the peak for NP. These findings demonstrated that microfluidization improved the solubility of NP in the formulations. The subsequent drug dissolution results were consistent with the DSC thermogram and PXRD pattern results. 3RH2/8, 3RH4/16, 3RH8/32, 5RH4/16, 5RH8/32, and 7RH8/32 were completely dissolved and showed higher dissolved NP amounts than 5RH2/8, 7RH2/8, 7RH4/16, and NP powder. The lowest mean dissolution time was for 7RH8/32 (13.31 ± 0.87 min). Caco-2 cells were used to determine drug uptake, and 7RH8/32 showed the maximum intracellular uptake (10.89%). After storage under accelerated and normal conditions (3 and 6 months), the selected formulations remained stable. The developed formulations can be used to improve NP solubility and absorption.

Formulation and Evaluation of Fenofibrate Dry Emulsion Tablets by Freeze Drying Method

Fenofibrate (FF) is a lipid-lowering agent classified in the biopharmaceutics classification system (BCS) class II with lower solubility and higher permeability. This research work deals with developing FF containing liquid self-micro emulsifying drug delivery system (L-SMEDDS) and converting it into solid SMEDDS (S-SMEDDS) using a lyophilization technique followed by the manufacturing of tablets with enhanced solubility and dissolution rate. L-SMEDDS of FF were manufactured using Tween 80, oleic acid, and transcutol. With the help of the lyophilization technique, this L-SMEDDS was converted to S-SMEDDS using microcrystalline cellulose and finally, immediate-release tablets were developed using S-SMEDDS. The L-SMEDDS showed excellent stability due to zeta potential of -1.69 mV and a globule size of 250 μm. The lyophilized S-SMEDDS of FF showed nearly 58-fold solubility enhancement in distilled water in comparison to pure FF due to the formation of amorphous material confirmed in the X-ray diffraction (XRD) study. The F9 formulation showed 100% drug release within 40 minutes with enhanced dissolution properties compared to conventional tablets. The optimized formulation was robust and stable at the accelerated condition for 3 months. The current research work demonstrates lyophilization as a potential approach to convert the L-SMEDSS to a S-SMEDDS with an enhanced solubility and dissolution rate.

Pickering Dry Emulsion System for Improved Oral Delivery of Fenofibrate.

The current study reports a Pickering dry emulsion (PDE) system for improved oral delivery of fenofibrate, a poorly water-soluble model drug. The silica nanoparticles were modified by surface modifiers and explored as a stabilizer for emulsion. The wetting property of modified silica nanoparticles was evaluated by contact angle study. Emulsion was spray-dried to obtain PDE. PDE was evaluated for particle size analysis, drug loading, TGA, DSC, XRPD, FEG-SEM, in vitro dissolution study, and in vivo pharmacodynamic study. The particle size of liquid emulsion was found within the range of 0.3-0.6 μm; after spray drying, the particles agglomerated and exhibited an increase in particle size (1.5 μm). The high drug loading (13% w/w) was found in PDE. DSC and XRD study confirmed the amorphous form of fenofibrate. SEM study showed the formation of a spherical porous microcapsule structure. In vitro dissolution exhibited significant enhancement in drug release for the PDE system as compared to plain fenofibrate. The PDE significantly lowered serum lipid level as compared to plain fenofibrate in a Triton-based hypercholesterolemia model in rats, which ultimately confirmed the enhancement in bioavailability. Thus, the PDE system has good potential in the drug delivery area.

Self-Nano Emulsifying Drug Delivery Systems

Lipid-based medication conveyance frameworks are widely announced in the writing for improving medication solvency, penetrability, and bioavailability. These frameworks incorporate straightforward oil arrangements, coarse, numerous, and dry emulsions, complex self-emulsifying, miniature emulsifying, or nano emulsifying drug conveyance frameworks. Self-emulsifying frameworks, further named self-miniature emulsifying drug conveyance frameworks (SMEDDS) and self-nano emulsifying drug conveyance frameworks (SNEDDS), are the most overall and economically feasible oil-based methodology for drugs that display low disintegration rate and insufficient retention. Since the time the advancement of SNEDDS, they attracted the interest of scientists request to manage the difficulties of inadequately water-solvent medications. SNEDDS is a demonstrated strategy for improving the dissolvability and bioavailability of lipophilic mixtures. Considering the simplicity of huge scope creation and the heartiness of SNEDDS, a few definitions methods are industrially accessible. The steadiness of SNEDDS can be additionally upgraded by cementing fluid SNEDDS. Controlled delivery and supersaturated SNEDDS got patient consistence with bigger medication stacking. The presence of biodegradable fixings and "medication focusing on valuable open doors" work with SNEDDS' clear legitimacy and differentiation among accessible dissolvability improvement strategies. In this article, an endeavour was made to introduce an outline of SNEDDS, their component, definition excipients, and possibilities of SNEDDS, late progressions, benefits, and inconveniences of SNEDDS details. The article additionally centers around assessing the use of SNEDDS in improving the bioavailability of antihypertensive medications. Keywords: Flavonoid, Therapeutic efficacy, Traditional medicine, Neuroprotective effect, Alternative therapy.

Relative bioavailability enhancement of simvastatin via dry emulsion systems: Comparison of spray drying and fluid bed layering technology

Comprehensive comparisons of similar lipid based drug delivery systems produced by different technologies are scarce. Spray drying and fluid bed layering technologies were compared with respect to the process and product characteristics of otherwise similar simvastatin loaded dry emulsion systems. Fluid bed layering provided higher process yield (83.3% vs 71.5%), encapsulation efficiency (80.0% vs 68.4%), relative one month product stability (93.8% vs 85.5%), larger and more circular particles (336 µm vs 56 µm) and lower median oil droplet size after product reconstitution in water (2.85 µm vs 4.27 µm), compared to spray drying. However, spray dried products exhibited higher drug content (22.2 mg/g vs 9.34 mg/g). An in-vivo pharmacokinetic study in rats was performed and a pharmacokinetic model was developed in order to compare the optimised simvastatin loaded dry emulsion systems, a simvastatin glyceride mimetic loaded in the dry emulsion and a simvastatin loaded SMEDDS with a reference physical mixture. Of the formulation tested, fluid bed layered pellets excelled and provided a 115% relative increase in bioavailability. Among the two technologies, fluid bed layering provided dry emulsion products with higher relative bioavailability and better product characteristics for further processing into final dosage forms.

In-vitro and in-vivo evaluation of taste-masked ibuprofen formulated in oral dry emulsions

Objective The aim of this study was to develop a paediatric oral preparation for ibuprofen. Significance Ibuprofen is widely used for defervescence in children, but medication compliance is poor due to its bitter taste. Dry emulsions possess good stability and can be transported and stored in solid form; they can be dispersed into liquid emulsions with water and easily administered to children. Methods In this study, a dry emulsion excipient was prepared by spray drying: a mixture of orange peel and corn oils (3:7, w/w) were used as the oil phase and solvent for ibuprofen; gum arabic and gum tragacanth were chosen as emulsifiers; and maltodextrin was used as a solid carrier. Results The particle sizes of the liquid and reconstituted emulsions were 5.75 μm and 6.11 μm, respectively; the average particle size distribution of the dry emulsion powder was 8.13 μm; scanning electron microscopy showed that the dry emulsion powder was composed of evenly distributed smooth spheres. At a drug loading of 36.52 ± 1.15 mg/g, 90% of ibuprofen was released from the dry emulsion excipient within 30 min. Sensory evaluations using human volunteers, rats and an electronic tongue demonstrated that the emulsion had a taste-masking effect on ibuprofen.It was further corroborated by in vivo studies using rat model that highlighted a 1.76-fold increase in ibuprofen absorption when the drug was administered as a emulsion compared with granules. Conclusions These results indicate that the dry emulsion for taste-masking is promising and valuable in the development of ibuprofen for pediatrics.

The Potential of Macroporous Silica-Nanocrystalline Cellulose Combination for Formulating Dry Emulsion Systems with Improved Flow Properties: A DoE Study.

The objective of this study was to explore the possible use of a new combination of two excipients, i.e., nanocrystalline cellulose (NCC) and macroporous silica (MS), as matrix materials for the compounding of dry emulsion systems and the effects these two excipients have on the characteristics of dry emulsion powders produced by the spray drying process. A previously developed liquid O/W nanoemulsion, comprised of simvastatin, 1-oleoyl-rac-glycerol, Miglyol 812 and Tween 20, was employed. In order to comprehend the effects that these two matrix formers have on the spray drying process and on dry emulsion powder characteristics, alone and in combination, a DoE (Design of Experiment) approach was used. The physicochemical properties of dry emulsion samples were characterised by atomic force microscopy, scanning electron microscopy, mercury intrusion porosimetry, energy-dispersive X-ray spectroscopy and laser diffraction analysis. Additionally, total release and dissolution experiments were performed to assess drug release from multiple formulations. It was found that the macroporous silica matrix drastically improved flow properties of dry emulsion powders; however, it partially trapped the oil—drug mixture inside the pores and hindered complete release. NCC showed its potential to reduce oil entrapment in MS, but because of its rod-shaped particles deposited on the MS surface, powder flowability was deteriorated.

Formulation and evaluation of raloxifene hydrochloride dry emulsion tablet using solid carrier adsorption technique.

Aim: The present study focused on the development of a dry emulsion tablet of raloxifene hydrochloride (RXF) using a solid carrier adsorption technique to enhance oral bioavailability. Methods: An oil-in-water emulsion was formulated and converted into dry powder using HPMC K4M plus Aerosil 200, then compressed into tablets. Results: The prepared emulsion was evaluated for globule size, drug content and zeta potential. In vitro release study revealed significantly higher release from emulsion. The prepared tablets possessed acceptable hardness, friability, weight variation, disintegration time, thickness, etc. In vivo pharmacokinetic studies indicated a more than sevenfold increase in oral bioavailability. Stability studies indicated good physical and chemical stability of the developed formulation. Conclusion: The authors successfully formulated dry emulsion tablets with enhanced oral bioavailability.

Enhancement of Aqueous Solubility and Oral Bioavailability of Bcs Class II Drug by Dry Emulsion

Liquid emulsions have distinct advantages over other dosage forms by improving oral bioavailability as well as by reducing the side effects. On contrary, liquid emulsion exhibit lack of physicochemical stability and compliance issues. To overcome these problems, dry emulsion formulation recommended. Dry emulsions are formulated by spray drying, evaporation and rotary evaporation. The aim of the present investigation is to improve the dissolution and oral bioavailability of poorly water soluble drug Olmesartan medoxomil by preparing dry emulsion. Olmesartan medoxomil is poorly soluble drug used for treatment of high blood pressure, showing absorption window at stomach and upper part of small intestine. Dry emulsion was ready by victimisation purgative during which drug is very soluble, using poloxamer188 as water soluble carrier and aerosil 200 as an adsorbent. The preferred oils were castor oil, olive oil, soybean oil and isopropyl myristate and polymers were PEG400, Eudragit EPO and Poloxamer 188. Dry emulsion was prepared by spray drying. Dry emulsion was evaluated for drug content, percentage moisture content, aqueous solubility, dissolution study and in-vivo bioavailability study. In vitro drug release of dry emulsion was studied by using USP type II paddle dissolution apparatus. The solubility of the drug was increased with surfactant and polymer at 1:1 ratio. Probable mechanisms of improved solubility were characterized by particle size determination, Differential Scanning Calorimetry (DSC), Powder X-ray Diffractometry (PXRD) and Scanning Electron Microscopy (SEM). This study revealed that solid dry emulsion technique could prove promising for improvement of solubility, dissolution rate and oral bioavailability of Olmesartan medoxomil.

A Comprehensive Review on Self-Nano Emulsifying Drug Delivery Systems: Advancements and Applications

Lipid-based drug delivery systems are extensively reported in literature for enhancing the drug solubility, permeability and bioavailability. These systems include simple oil solutions, coarse, multiple and dry emulsions, complex self-emulsifying, microemulsifying or nanoemulsifying drug delivery systems. Self-emulsifying systems are further classified as self-microemulsifying drug delivery systems (SMEDDS) and self-nanoemulsifying drug delivery systems (SNEDDS) are most prevailing and commercially viable oil based approach for drugs that exhibit low dissolution rate and inadequate absorption. Ever since the progress of SNEDDS, they drew the interest of researchers in order to deal with the challenges of poorly water-soluble drugs. SNEDDS is a proven method for enhancing solubility and bioavailability of lipophilic compounds. Considering the ease of large-scale production and the robustness of SNEDDS, several formulations techniques are commercially available. The stability of SNEDDS can be further enhanced by solidifying liquid SNEDDS. Controlled release and supersaturated SNEDDS received patient compliance with larger drug loading. Presence of biodegradable ingredients and ‘drug-targeting opportunities’ facilitate SNEDDS a clear merit and distinction amongst available solubility enhancement techniques. In this article attempt was made to present an overview of SNEDDS, their mechanism, formulation excipients and potentials of SNEDDS, recent advancements, advantages and disadvantages of SNEDDS formulations. The article also focuses on reviewing the application of SNEDDS in enhancing bioavailability of antihypertensive drugs.

Dry Emulsions based on Alpha Cyclodextrin and Vegetable Oils for Buccal Delivery of Lipophilic Drugs

Background: Buccal delivery of drugs can be used as an alternative administration route to conventional oral route avoiding the liver first-pass effect and improving patient compliance. Objective: The goal of this work was to develop dry emulsions for buccal delivery of ketoprofen, used as a lipophilic model drug. The influence of two vegetable oils, olive oil or wheat germ oil, in the presence of α-cyclodextrin and different drying techniques on the dry emulsion properties was evaluated. Methods: Emulsions were prepared by adding olive oil or wheat germ oil to an aqueous solution of α-cyclodextrin and subsequently dried through an oven, freeze-dryer or spray-dryer. Dry emulsions were characterized in terms of yield, encapsulation efficiency, morphology and drug solid-state. In vitro drug release and permeation studies were carried out to evaluate dry emulsion ability to release the drug and to allow its permeation through the esophageal porcine epithelium. Results: The formation of stable and milky emulsion was assured by cyclodextrin ability to interact with oil components obtaining an inclusion complex with amphiphilic property able to act as a surfaceactive agent. The drying process influenced the yield and the encapsulation efficiency, while no significant differences were observed between olive oil and wheat germ oil. Freeze-dried emulsions, selected as the best formulations, resulted in fast release of drug thereby ensuring its permeation across the epithelium. Conclusion: Dry emulsions prepared with a simple and easy method, using natural ingredients and avoiding synthetic surfactants and organic solvents, could be used for buccal delivery of lipophilic drugs.