Thermodynamic stability, in-vitro permeability, and in-silico molecular modeling of the optimal Elaeis guineensis leaves extract water-in-oil nanoemulsion.

Nanoemulsion is a delivery system used to enhance bioavailability of plant-based compounds across the stratum corneum. Elaeis guineensis leaves are rich source of polyphenolic antioxidants, viz. gallic acid and catechin. The optimal E. guineensis leaves extract water-in-oil nanoemulsion was stable against coalescence, but it was under significant influence of Ostwald ripening over 90 days at 25 °C. The in-vitro permeability revealed a controlled and sustained release of the total phenolic compounds (TPC) of EgLE with a cumulative amount of 1935.0 ± 45.7 µgcm-2 after 8 h. The steady-state flux and permeation coefficient values were 241.9 ± 5.7 µgcm-2 h-1 and 1.15 ± 0.03 cm.h-1, respectively. The kinetic release mechanism for TPC of EgLE was best described by the Korsmeyer-Peppas model due to the highest linearity of R2 = 0.9961, indicating super case II transport mechanism. The in-silico molecular modelling predicted that the aquaporin-3 protein in the stratum corneum bonded preferably to catechin over gallic acid through hydrogen bonds due to the lowest binding energies of - 57.514 kcal/mol and - 8.553 kcal/mol, respectively. Thus, the in-silico study further verified that catechin could improve skin hydration. Therefore, the optimal nanoemulsion could be used topically as moisturizer to enhance skin hydration based on the in-silico prediction.

Evaluation of the efficacy and safety of a new formulation-lipid emulsion-based PTX injection: Pharmacokinetics, tissue distributions and anticancer effect on human gastric cancer cells in vitro.

Paclitaxel (PTX) is one of the most widely used chemotherapeutic agents. The commercial PTX formulation was based on Cremophor EL and ethanol owing to its poor aqueous solubility. However, Cremophor EL has been shown to cause toxic effects such as life-threatening anaphylaxis. In our study, we diluted PTX in a commercially available 20% (w/v) lipid emulsion (Lip-PTX) in order to avoid Cremophor EL. The purpose of this study was to evaluate the pharmacokinetics and tissue distributions between Lip-PTX and PTX injection. We also investigated the effects of Lip-PTX and PTX injection on human gastric cancer cells HGC-27 by MTT assay. The apoptosis was detected by flow cytometry with Annexin V/propidium iodide (PI) double staining. Furthermore, the safety such as acute toxicity was also assessed. The results showed that PTX in Sprague-Dawley rats administered Lip-PTX exhibited extended half-life, increased clearance (P < 0.05) and smaller area under the concentration-time curve compared with PTX injection and there was little significant difference in the distribution of PTX in Sprague-Dawley rats or tumor-bearing mice between Lip-PTX and PTX injection. The cells treated with Lip-PTX had a higher percentage of apoptosis and a higher G2 /M phase ratio, which indicated that the anticancer effect of Lip-PTX was significantly better than that of PTX injection. Moreover, our study highlighted the safety of Lip-PTX. This study demonstrated the feasibility and potential advantages of Lip-PTX for clinical therapy.

A novel irinotecan-lipiodol nanoemulsion for intravascular administration: pharmacokinetics and biodistribution in the normal and tumor bearing rat liver.

Colorectal cancer is one of the most common cancers in the United States and treatment options are limited for patients who develop liver metastases. Several chemotherapeutic regimens have been used for transvascular liver-directed therapy in the treatment of colorectal liver metastases without clear evidence of superiority of one therapy over another. We describe the development of a novel nanoemulsion through combining irinotecan (IRI), a first line systemic agent used for the treatment of colon cancer, with lipiodol, an oily contrast medium derived from poppy seed oil, and evaluated its pharmacokinetic and biodistribution profile as a function of portal venous chemoembolization (PVCE) versus transarterial chemoembolization (TACE) delivery. The Tessari technique was used to create a stable emulsion (20 mg IRI mixed with 2 mL lipiodol) with resultant particle size ranging from 28.9 nm to 56.4 nm. Pharmacokinetic profile established through venous sampling in Buffalo rats demonstrate that the area under the curve (AUC0-∞) of IRI was significantly less after PVCE with IRI-lipiodol as compared to IRI alone (131 vs. 316 µg*min/mL, p-value = .023), suggesting significantly higher amounts of IRI retention in the liver with the IRI-lipiodol nanoemulsion via first-pass extraction. Subseqent biodistribution studies in tumor-bearing WAG/Rjj rats revealed more IRI present in the tumor following TACE versus PVCE (29.19 ± 12.33 µg/g versus 3.42 ± 1.62; p-value = .0033) or IV (29.19 ± 12.33 µg/g versus 1.05 ± 0.47; p-value = .0035). The IRI-lipiodol nanoemulsion demonstrated an acceptable hepatotoxicity profile in all routes of administration. In conclusion, the IRI-lipiodol nanoemulsion via TACE showed promise and warrants further investigation as an option for the treatment of metastatic colorectal cancer.

Role of antioxidants on physicochemical properties and in vitro bioaccessibility of ß-carotene loaded nanoemulsion under thermal and cold plasma discharge accelerated tests.

The effects of water soluble antioxidant (ascorbic acid and EDTA), fat soluble antioxidant (α-tocopherol) and amphiphilic antioxidant (ascorbyl palmitate; AP) on the chemical physics and bioaccessibility of ß-carotene loaded nanoemulsions (CNE) were investigated. During accelerated storage at 45 °C for 15 days, AP showed the highest protective actions against particle size growth, color fading, lipid oxidation, and ß-carotene degradation in CNE (p < 0.05). CNE with AP was then subjected to treat with cold plasma (CP) induced reactive species system under various powers and contact times compared to control. AP was able to protect physical and oxidative stabilities of CNE as well as ß-carotene integrity. The highest in vitro lipid digestibility, bioaccessibility and ß-carotene stability were found in CNE with AP (p < 0.05). However, those properties were lowered after CP exposure. The results indicated that AP was a promising antioxidant in improving physical stability, oxidative stability, ß-carotene retention, and ß-carotene bioaccessibility of CNE.

Intranasal administration of perillyl alcohol-loaded nanoemulsion and pharmacokinetic study of its metabolite perillic acid in plasma and brain of rats using ultra-performance liquid chromatography/tandem mass spectrometry.

Perillyl alcohol (POH) is a monocyclic terpene that has strong antitumor activity. Brain tumors are particularly difficult to treat with therapeutic agents, and clinical trials have shown their low tolerance through oral administration. We proposed the entrapment of POH into an oil-in-water chitosan nanoemulsion aiming its intranasal administration for brain targeting. An ultra-performance liquid chromatography/tandem mass spectrometry (UPLC-MS/MS) method was developed and validated for the quantitation of total metabolite perillic acid (PA) in plasma and brain of rats. The rat samples containing the metabolite were treated by liquid-liquid extraction with acetonitrile. The mobile phase was 0.1% formic acid in water (solvent A) and 0.1% formic acid in methanol (solvent B), at a flow rate of 0.3 mL min-1 in gradient elution. The chromatography was run for 10 min, and analytical curves were built in acetonitrile, plasma, and brain. The PA was detected in positive ion mode with multiple reaction monitoring. The method has shown high selectivity, sensitivity, and throughput. The low quantification limits of 162, 178, and 121 ng mL-1 for acetonitrile, brain, and plasma, respectively, indicate a good detectability of the method. The repeatability and precision observed were within the limits recommended in the literature. The accuracy of the method was verified through high recovery rates (106-118%). The validated method was successfully applied to the pharmacokinetic study of the metabolite PA after the intranasal administration of free or POH-loaded nanoemulsion in rats. The results showed that chitosan nanoemulsion improved the plasma and brain bioavailability of POH, representing a promising alternative to free POH treatment.

Avocado-derived polyols for use as novel co-surfactants in low energy self-emulsifying microemulsions.

Avocado (Persea americana Mill.; Lauraceae) seed-derived polyhydroxylated fatty alcohols (PFAs) or polyols (i.e., avocadene and avocadyne) are metabolic modulators that selectively induce apoptosis of leukemia stem cells and reverse pathologies associated with diet-induced obesity. Delivery systems containing avocado polyols have not been described. Herein, natural surface active properties of these polyols are characterized and incorporated into self-emulsifying drug delivery systems (SEDDS) that rely on molecular self-assembly to form fine, transparent, oil-in-water (O/W) microemulsions as small as 20 nanometers in diameter. Mechanistically, a 1:1 molar ratio of avocadene and avocadyne (i.e., avocatin B or AVO was shown to be a eutectic mixture which can be employed as a novel, bioactive, co-surfactant that significantly reduces droplet size of medium-chain triglyceride O/W emulsions stabilized with polysorbate 80. In vitro cytotoxicity of avocado polyol-SEDDS in acute myeloid leukemia cell lines indicated significant increases in potency and bioactivity compared to conventional cell culture delivery systems. A pilot pharmacokinetic evaluation of AVO SEDDS in C57BL/6J mice revealed appreciable accumulation in whole blood and biodistribution in key target tissues. Lastly, incorporation of AVO in SEDDS significantly improved encapsulation of the poorly water-soluble drugs naproxen and curcumin.

Efficacy and Pharmacokinetic Considerations of Loratadine Nanoformulations and its Combinations for Pancreatic Cancer Chemoprevention.

PURPOSE: Pancreatic cancer (PC) is predicted to become the second leading cause of cancer associated deaths by 2020. Earlier, we confirmed the development and efficacy of our novel Loratadine Self-Microemulsifying-Drug-Delivery-System - Sulforaphane (LOR SMEDDS -SFN) nanoformulation in PC chemoprevention. In this report, we extend our studies to evaluate the PC chemoprevention efficacy of LOR SMEDDS - SFN. METHODS: The nanoformulation was subjected to in vitro colony formation assays, in vivo oral pharmacokinetics and stability studies. RESULTS: The colony formation assay using Panc-1 PC cells demonstrated a survival fraction of 0.74 with LOR-SFN (p < 0.001) which further reduced to 0.35 with LOR SMEDDS-SFN treatment (p < 0.0001) confirming the synergistic chemoprevention efficacy of the nanoformulation. Further, the oral pharmacokinetic studies of LOR SMEDDS-SFN showed 4-fold and 9-fold increase in Cmax (503.2 ± 5.8 ng/mL) and oral bioavailability (20,274.8 ± 3711.0 ng·h/mL) for LOR compared to LOR-SFN combination respectively assuring the enhanced performance by the SMEDDS. Additionally, the formulation exhibited statistically non-significant alteration in globule size, zeta potential, drug content and in vitro drug release during stability studies confirming its stability and pharmaceutical acceptability. CONCLUSION: Our studies have demonstrated a potential of LOR SMEDDS-SFN nanoformulation as an effective PC chemoprevention strategy.

Fabrication of pea protein-tannic acid complexes: Impact on formation, stability, and digestion of flaxseed oil emulsions.

There is growing interest in the identification of plant-based functional ingredients for utilization within the food industry. Complexes were fabricated from pea protein (PP) and tannic acid (TA) and then their ability to act as antioxidant emulsifiers in flaxseed oil-in-water emulsions was studied. PP-TA complex formation was investigated using isothermal titration calorimetry and turbidity analysis, which suggested hydrogen bonding and hydrophobic interactions were important in their assembly. PP-TA-stabilized emulsions containing small droplets could be formed at relatively high TA levels. Moreover, PP-TA complexes had strong antioxidant activity, which extended the shelf life of flaxseed oil emulsions. The composition of the PP-TA complexes impacted the aggregation state of the lipid droplets under simulated gastric conditions, which affected the rate and extent of lipid digestion. This study shows PP-TA complexes can be used for fabricating flaxseed oil delivery systems with enhanced oxidative stability and good digestibility.

Extraction, formulation and characterization of an in vitro and ex-vivo evaluation of Thymus serpyllum L. (Thymus oil) from topical preparations using dialysis cellulose membrane and natural rabbit skin.

Herbal remedies like the Thymus serpyllum L. is useful in traditional medicine for the treatment of many diseases especially congestion, and bronchitis. The purpose of this study was to formulate a micro-emulsion, a gel and an ointment containing the plant hydro distilled thymus oil extracted from Thymus serpyllum L. collected from Ziarat, Balochistan. The prepared formulations were subjected to in-vitro and ex vivo study release, High performance Liquid Chromatography (HPLC), Thin Layer Chromatography (TLC), to justify their suitability for topical use. The in-vitro and ex-Vivo release was studied using Franz Cells and using two different kinds of membrane synthetic dialysis cellulose membrane and natural rabbit skin and the amount of drug released was determined by HPLC at λ 274nm. The three formulations result obtained through dialysis cellulose membrane showed the faster release than the natural rabbit skin. However, the micro-emulsion, gel formulation showed the same release except ointment. The release from the above mentioned formulation can be arranged in the following descending order. micro-emulsion > Gel > Ointment. The best fit of release kinetics was achieved by Krosmeyer- Peppas, the TLC and HPLC identifies the Thymol, isolation and quantification of the marker. This study demonstrates that it is necessary to assess the impact of release and permeability pattern of different formulations. In vitro and ex-vivo diffusion cell experiments can be utilized to develop formulations of traditional medicines identifies.

Hydroxytyrosol encapsulated in biocompatible water-in-oil microemulsions: How the structure affects in vitro absorption.

Over the last years, the incorporation of natural antioxidants in food and pharmaceutical formulations has gained attention, delaying or preventing oxidation phenomena in the final products. In order to take full advantage of their properties, protection in special microenvironments is of great importance. The unique features of the natural phenolic compound hydroxytyrosol (HT) - including antioxidant, anti-inflammatory, antiproliferative and cardioprotective properties - have been studied to clarify its mechanism of action. In the present study novel biocompatible water-in-oil (W/O) microemulsions were developed as hosts for HT and subsequently examined for their absorption profile following their oral uptake. The absorption of HT in solution was compared with the encapsulated one in vitro, using a coculture model (Caco-2/TC7 and HT29-MTX cell lines). The systems were structurally characterized by means of Dynamic Light Scattering (DLS) and Electron Paramagnetic Resonance (EPR) techniques. The diameter of the micelles remained unaltered after the incorporation of 678 ppm of HT but the interfacial properties were slightly affected, indicating the involvement of the HT molecules in the surfactant monolayer. EPR was used towards a lipophilic stable free radial, namely galvinoxyl, indicating a high scavenging activity of the systems and encapsulated HT. Finally, after the biocompatibility study of the microemulsions the intestinal absorption of the encapsulated HT was compared with its aqueous solution in vitro. The higher the surfactants' concentration in the system the lower the HT concentration that penetrated the constructed epithelium, indicating the involvement of the amphiphiles in the antioxidant's absorption and its entrapment in the mucus layer.

Comparison of ocular pharmacokinetics of etoposide and its nanoemulsion after subtenon administration in rabbits.

Background Subtenon anticancer drugs are given as an adjunct to systemic chemotherapy for conditions like retinoblatoma. This study evaluated the ocular kinetics of nano-emulsion formulation of etoposide (NanoEt) and compared it with an equal dose of commercially available alcohol-based etoposide formulation in healthy rabbits. Methods A nanoemulsion formulation of NanoEt was developed and then evaluated for its ocular kinetics by subtenon administration in healthy rabbits. After the sterile subtenon administration of the drug, the eyes were enucleated after CO2 euthanasia at time intervals of 2 h, 6 h, 12 h, and 24 h, and ocular tissues, blood, and plasma were separated. The concentration of etoposide in the ocular tissues and blood was quantified using liquid chromatography tandem mass spectrometry (LC MS/MS). Results This study found that subtenon injection of NanoEt showed 24 times higher concentration in rabbit retina compared to an equal dose of conventional marketed formulation. Based on the ocular tissue bioavailability calculations (AUC0-24), the present study revealed that the formulation enhanced 90% ocular bioavailability of etoposide, when it was injected in the form of nano-emulsion in most of the tissues. Conclusions NanoEt has better bioavailability compared to the commercial alcohol-based formulation for subtenon injection. Low systemic exposure showed further advantage for its projected use in retinoblastoma (Rb) as an adjunct therapy. Further studies in Rb animal models are required to evaluate its safety and efficacy, for its clinical utility.

Novel cuminaldehyde self-emulsified nanoemulsion for enhanced antihepatotoxicity in carbon tetrachloride-treated mice.

OBJECTIVES: Cuminaldehyde self-emulsified nanoemulsion (CuA-SEN) was prepared and optimised to improve its oral bioavailability and antihepatotoxicity. METHODS: Cuminaldehyde self-emulsified nanoemulsion was developed through the self-nanoemulsification method using Box-Behnken Design (BBD) tool while appropriate physicochemical indices were evaluated. The optimised CuA-SEN was characterised via droplet size (DS), morphology, polydispersity index (PDI), zeta potential (ZP), entrapment efficiency, in-vitro release, and pharmacokinetic studies while its antihepatotoxicity was evaluated. KEY FINDINGS: Cuminaldehyde self-emulsified nanoemulsion with acceptable characteristics (mean DS-48.83 ± 1.06 nm; PDI-0.232 ± 0.140; ZP-29.92 ± 1.66 mV; EE-91.51 ± 0.44%; and drug-loading capacity (DL)-9.77 ± 0.75%) was formulated. In-vitro drug release of CuA-SEN significantly increased with an oral relative bioavailability of 171.02%. Oral administration of CuA-SEN to CCl4 -induced hepatotoxicity mice markedly increased the levels of superoxide dismutase, glutathione and catalase in serum. Also, CuA-SEN reduced the levels of tumour necrosis factor-alpha and interleukin-6 in both serum and liver tissues while aspartate aminotransferase, alanine aminotransferase and malonaldehyde levels were significantly decreased. CONCLUSIONS: These findings showed that the improved bioavailability of cuminaldehyde via SEN provided an effective approach for enhancing antioxidation, anti-inflammation and antihepatotoxicity of the drug.

HPLC-UV method for temozolomide determination in complex biological matrices: Application for in vitro, ex vivo and in vivo studies.

A high-performance liquid chromatography method for temozolomide (TMZ) determination in complex biological matrices was developed and validated for application in in vitro, ex vivo and in vivo studies of new nanotechnology-based systems for TMZ nasal delivery. The method was able to quantify TMZ in nanoemulsions, following cellular uptake, in the porcine nasal mucosa and in mouse plasma and brain. Analyses were performed on a C18 column at 35°C, under UV detection at 330 nm. The mobile phase was methanol-acetic acid 0.5% (30:70, v/v), eluted at an isocratic flow rate of 1.1 mL/min. The method was found to be specific, precise, accurate, robust and linear (0.05 to 5 µg/mL) for TMZ determination in all matrices. No interference of TMZ degradation products was found under various stress conditions such as acidic, alkaline, oxidative, light and thermal exposure, demonstrating stability. The method was applied for the quantification of TMZ in different matrices, i.e. the efficiency of nanoemulsions in vitro in increasing TMZ cellular uptake, ex vivo TMZ permeation and retention in the porcine nasal mucosa tissue, and for in vivo TMZ quantification in mouse brain following intranasal nanoemulsion administration compared with free TMZ.

Effects of nano-sizing on lipid bioaccessibility and ex vivo bioavailability from EPA-DHA rich oil in water nanoemulsion.

The physiological efficacy of nutraceuticals is dependent on their physicochemical nature and bioavailability across biological barriers. In the present work, effects of nano-sizing of emulsion-based delivery vehicle on the bioavailability of polyunsaturated fatty acids rich fish oil have been investigated via three-step experimental design; ex vivo rat everted intestinal sac model, cellular lipid uptake and the bioactivity in rat PBMCs. Nanoemulsion in comparison to the conventional emulsion has shown significant higher rate of uptake of polyunsaturated fatty acids in three segments of small intestine. The time-kinetics of such uptake was correlated with appearance of short-chain fatty acids in basal side of the everted sac. The bioavailability of the formulated fish oil and its inhibitory response against lipopolysaccharide-induced nitric oxide production in rat PBMCs were positively correlated. This formulation with nano-sized droplets can be utilized as smart delivery vehicles for designing oral therapies in future.

Improving maraviroc oral bioavailability by formation of solid drug nanoparticles.

Oral drug administration remains the preferred approach for treatment of HIV in most patients. Maraviroc (MVC) is the first in class co-receptor antagonist, which blocks HIV entry into host cells. MVC has an oral bioavailability of approximately 33%, which is limited by poor permeability as well as affinity for CYP3A and several drug transporters. While once-daily doses are now the favoured option for HIV therapy, dose-limiting postural hypotension has been of theoretical concern when administering doses high enough to achieve this for MVC (particularly during coadministration of enzyme inhibitors). To overcome low bioavailability and modify the pharmacokinetic profile, a series of 70 wt% MVC solid drug nanoparticle (SDN) formulations (containing 30 wt% of various polymer/surfactant excipients) were generated using emulsion templated freeze-drying. The lead formulation contained PVA and AOT excipients (MVCSDNPVA/AOT), and was demonstrated to be fully water-dispersible to release drug nanoparticles with z-average diameter of 728 nm and polydispersity index of 0.3. In vitro and in vivo studies of MVCSDNPVA/AOT showed increased apparent permeability of MVC, compared to a conventional MVC preparation, with in vivo studies in rats showing a 2.5-fold increase in AUC (145.33 vs. 58.71 ng h ml-1). MVC tissue distribution was similar or slightly increased in tissues examined compared to the conventional MVC preparation, with the exception of the liver, spleen and kidneys, which showed statistically significant increases in MVC for MVCSDNPVA/AOT. These data support a novel oral format with the potential for dose reduction while maintaining therapeutic MVC exposure and potentially enabling a once-daily fixed dose combination product.

Effects of D-α-tocopherol polyethylene glycol succinate-emulsified poly(lactic-co-glycolic acid) nanoparticles on the absorption, pharmacokinetics, and pharmacodynamics of salinomycin sodium.

Although salinomycin sodium (SS) has shown in-vitro potential to inhibit cancer stem cell growth and development, its low water solubility makes it a poor candidate as an oral chemotherapeutic agent. To improve the bioavailability of SS, SS was encapsulated here using D-α-tocopherol polyethylene glycol succinate (TPGS)-emulsified poly(lactic-co-glycolic acid) (PLGA) nanoparticles and compared with its parent SS in terms of absorption, pharmacokinetics, and efficacy in suppressing nasopharyngeal carcinomas stem cells. The pharmacokinetics of SS and salinomycin sodium-loaded D-α-tocopherol polyethylene glycol succinate-emulsified poly(lactic-co-glycolic acid) nanoparticles (SLN) prepared by nanoprecipitation were analyzed in-vivo by timed-interval blood sampling and oral administration of SS and SLN to rats. Sensitive liquid chromatography-mass spectrometry (LC-MS) was developed to quantify plasma drug concentrations. SS and SLN transport in Caco-2 cells was also investigated. The therapeutic efficacy of SS and SLN against cancer stem cells was determined by orally administering the drugs to mice bearing CNE1 and CNE2 nasopharyngeal carcinoma xenografts and then evaluating CD133 cell proportions and tumorsphere formation. The in-vivo trial with rats showed that the Cmax, AUC(0-t), and Tmax for orally administered SLN were all significantly higher than those for SS (P<0.05). These findings were corroborated by a Caco-2 cell Transwell assay showing that relative SLN absorption was greater than that of SS on the basis of their apparent permeability coefficients (Papp). Significantly, therapeutic SLN efficacy against nasopharyngeal carcinoma stem cells was superior to that of SS. TPGS-emulsified PLGA nanoparticles effectively increase SS solubility and bioavailability. SLN is, therefore, promising as an oral chemotherapeutic agent against cancer stem cells.

Development, Characterization, and Pharmacokinetic Evaluation of a CRV431 Loaded Self-Microemulsifying Drug Delivery System.

PURPOSE: The objective of this study was to develop a self-microemulsifying drug delivery system (SMEDDS) formulation for the oral delivery of CRV431, a non-immunosuppressive analogue of cyclosporine A. Relative to cyclosporine A, CRV431 is poorly soluble in lipid solvents and thusly presents a challenge for the development of a formulation of sufficient oral bioavailability for clinical use. METHODS: The solubility of CRV431, a cyclosporine derivative, was determined in a range of commonly used surfactants, oils and co-solvents. A pseudo-ternary phase diagram was constructed from the most soluble excipients and prototype formulations, SERIES 1 and SERIES 2 were developed. The pharmacokinetics, following single oral doses of 1 and 3 mg/kg of CRV431 SMEDDS, was studied in healthy human volunteers using liquid chromatography-electrospray ionization-mass spectrometry (LC-ESI-MS). RESULTS: The maximum drug load for the SERIES 1 formulations was less than 40 mg/ml. Manipulation of the excipient ratios allowed for the development of SERIES 2 formulations, which had higher drug loading capacity and stability for CRV431 compared to SERIES 1. Further improvements allowed for the development of an optimized SMEDDS formulation containing up to 90 mg/ml CRV431 and which generated a microemulsion mean particle size of 25 nm when dispersed into aqueous media. The pharmacokinetics of the optimized CRV431 SMEDDS displayed excellent total body exposure and dose-proportional effects in humans, and high drug levels in the liver of rats. CONCLUSIONS: The developed SMEDDS formulation should allow for effective clinical development of CRV431, targeted to the treatment of liver diseases including hepatitis B (HBV), fibrosis, and hepatocellular carcinoma.

Nano-sized Droplets of Self-Emulsifying System for Enhancing Oral Bioavailability of Chemotherapeutic Agent VP-16 in Rats: A Nano Lipid Carrier for BCS Class IV Drugs.

PURPOSE: The purpose of this study was to investigate the ability of a self-nano-emulsifying drug delivery system (SNEDDS) to enhance the oral bioavailability of a BCS class IV drug, etoposide (VP-16). METHOD: A series of SNEDDS formulations with VP-16 were prepared consisting of medium chain triglycerides, polysorbate 80, diethylene glycol monoethyl ether and propylene glycol monolaurate type-1.  Based on an obtained ternary phase diagram, an optimum formulation was selected and characterized in terms of size, zeta potential, loading, morphology and in vitro drug release. The pharmacokinetic parameters and oral bioavailability of VP-16 suspension and VP-16 in SNEDDS was assessed using 30 Male Sprague-Dawley rats and compared with the commercial product (VePesid®). RESULTS: Pharmacokinetic data showed that the mean values for AUC0-t of VP-16 in SNEDDS was 6.4 fold higher compared to a drug suspension and 2.4-folds higher than VePesid®. Similarly, the mean value for Cmax of VP-16 in SNEDDS (1.13± 0.07 µg/ml µg.h/mL) was higher than VePesid® (0.62± 0.09 µg/mL) and drug suspension (0.13± 0.07 µg/mL). CONCLUSION: The SNEDDS formulation was able to enhance the oral bioavailability of the BCS Class IV chemotherapeutic agent VP-16 by increasing the dissolution and absorption of the drug. A good in vitro in vivo correlation was found between the in vitro dissolution and in vivo absorption data of VP-16 SNEDDS preparation. Therefore, SNEDDS formulations might be a very promising approach for BCS Class IV drugs.

In vitro and ex-vivo evaluation of topical formulations designed to minimize transdermal absorption of Vitamin K1.

Topical application of Vitamin K1 has been demonstrated to effectively treat papulopustular skin rash, a serious and frequently encountered side effect of Epidermal Growth Factor Inhibitors (EGFRIs). Systemic absorption of vitamin K1 from skin and the resultant consequence of antagonizing EGFRIs anticancer effects jeopardizes the clinical acceptability of this rather effective treatment. The purpose of the present study was to rationally formulate and evaluate the release rate and transdermal absorption of a wide range of Vitamin K1 dermal preparations with a variety of physiochemical properties. A library of 33 formulations with were compounded and tested for Vitamin K1 permeation using hydrophobic membranes and porcine skin mounted in a Fran diffusion cells. Our results demonstrate the lowest diffusion for water-in-oil emulsions, which also demonstrated a negligible transdermal absorption. The statistical analysis showed a significant correlation between in vitro and ex vivo results. While viscosity did not have a significant impact on the diffusion or absorption of vitamin K1, an increase in the lipid content was correlated with an increase in transmembrane diffusion (not with transdermal absorption). Overall, formulation design significantly impacts the release rate and transdermal absorption of vitamin K1, and confirms the possibility of minimal systemic distribution of this vitamin for this specific purpose.

Enhanced oral absorption of pemetrexed by ion-pairing complex formation with deoxycholic acid derivative and multiple nanoemulsion formulations: preparation, characterization, and in vivo oral bioavailability and anticancer effect.

OBJECTIVE: The current study sought to design an oral delivery system of pemetrexed (PMX), a multitargeted antifolate antimetabolite, by enhancing its intestinal membrane permeability. MATERIALS AND METHODS: PMX was ionically complexed with a permeation enhancer such as Nα-deoxycholyl-l-lysyl-methylester (DCK) and prepared as an amorphous solid dispersion by mixing with dispersants such as 2-hydroxypropyl-beta-cyclodextrin (HP-beta-CD) and poloxamer 188 (P188), forming an HP-beta-CD/PMX/DCK/P188; the complex was incorporated into multiple water-in-oil-in-water nanoemulsions in a supersaturated state (HP-beta-CD/PMX/DCK/P188-NE). RESULTS: After complex formation, the partition coefficient and in vitro membrane permeability of PMX were markedly increased, but it showed similar cytotoxic and inhibitory effects on cancer cell proliferation/migration. Furthermore, the intestinal membrane permeability and epithelial cell uptake of PMX were synergistically improved after HP-beta-CD/PMX/DCK/P188 was incorporated into a nanoemulsion with a size of 14.5±0.45 nm. The in vitro permeability of HP-beta-CD/PMX/DCK/P188-NE across a Caco-2 cell monolayer was 9.82-fold greater than that of free PMX, which might be attributable to the partitioning of PMX to the epithelial cells being facilitated via specific interaction of DCK with bile acid transporters, as well as the enhanced lipophilicity accompanied by surfactant-induced changes in the intestinal membrane structure and fluidity. Therefore, the oral bioavailability of HP-beta-CD/PMX/DCK/P188-NE in rats was evaluated as 26.8%±2.98% which was 223% higher than that of oral PMX. Moreover, oral HP-beta-CD/PMX/DCK/P188-NE significantly suppressed tumor growth in Lewis lung carcinoma cell-bearing mice, and the tumor volume was maximally inhibited by 61% compared with that in the control group. CONCLUSION: These results imply that HP-beta-CD/PMX/DCK/P188-NE is an effective and promising delivery system for enhancing the oral absorption of PMX. Thus, there is the potential for new medical applications, including applications in metronomic cancer treatment.