Nanoemulsions containing Garcinia mangostana L. pericarp extract for topical applications: Development, characterization, and in vitro percutaneous penetration assay.

A highly stable oil-in-water nanoemulsion for topical applications, containing mangostins extracted from the pericarp of mangosteen (Garcinia mangostana L.), is a promising strategy to protect mangostins as well as to improve penetration of these important antioxidants through the skins. Nanoemulsions consisted of virgin coconut oil as the oil phase, Tween-80 and Span-80 as surfactants, and xanthan gum as the thickening agent, were prepared using the high-energy and low-energy emulsification methods. The nanoemulsions that were stable up to 28 days had oil droplet diameter of 220 nm to 353 nm and zeta potential of -46.9 mV to -63.7 mV. The accelerated stability test showed that the most stable nanoemulsions were those prepared using the low-energy emulsification method with an estimated shelf life of eleven months, composed of 11% oil phase, 17% surfactant, and 72% aqueous phase. The in vitro percutaneous penetration test for the nanoemulsion with added xanthan gum provided high cumulative skin penetration of mangostins of up to 114 µg/cm2. The results of this study indicate that virgin coconut oil-based nanoemulsions containing mangostins, prepared using the low-energy emulsification method, stabilized by xanthan gum and mixed at 40°C can prospectively be used for topical applications.

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.

New potential application of hydroxypropyl-ß-cyclodextrin in solid self-nanoemulsifying drug delivery system and solid dispersion.

The purpose of this study was to use hydroxypropyl-ß-cyclodextrin (HP-ß-CD) as a novel carrier in solid SNEDDS and solid dispersions to enhance the solubility and oral bioavailability of poorly water-soluble dexibuprofen. The novel dexibuprofen-loaded solid SNEDDS was composed of dexibuprofen, corn oil, polysorbate 80, Cremophor® EL, and HP-ß-CD at a weight ratio of 45/35/50/15/100. This solid SNEDDS spontaneously formed a nano-emulsion with a size of approximately 120 nm. Unlike the conventional solid SNEDDS prepared with colloidal silica as a carrier, this dexibuprofen-loaded solid SNEDDS exhibited a spherical structure. Similar to the dexibuprofen-loaded solid dispersion prepared with HP-ß-CD, the transformation of the crystalline drug to an amorphous state with no molecular interactions were observed in the solid SNEDDS. Compared to the solid dispersion and dexibuprofen powder, solid SNEDDS significantly enhanced drug solubility and AUC. Therefore, HP-ß-CD is a novel potential carrier in SNEDDS for improving the oral bioavailability of dexibuprofen.

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.

Preparation, characterization, and evaluation of antioxidant activity and bioavailability of a self-nanoemulsifying drug delivery system (SNEDDS) for buckwheat flavonoids.

The self-nanoemulsifying drug delivery system has shown many advantages in drug delivery. In this study, a self-nanoemulsifying drug delivery system of buckwheat flavonoids was prepared for enhancing its antioxidant activity and oral bioavailability. A nanoemulsion of buckwheat flavonoids was developed and characterized, and its antioxidant, in vitro release, and in vivo bioavailability were determined. The nanoemulsion was optimized by the central composite design response surface experiment, and its particle size, polymer dispersity index (PDI), zeta potential, morphology, encapsulation efficiency, and stability were evaluated. The antioxidant activity was tested by measuring its 2,2-diphenyl-1-picrylhydrazyl scavenging activity, hydroxyl radical scavenging activity, and superoxide anion scavenging ability. In vitro release of buckwheat flavonoids nanoemulsion showed a higher cumulative release than the suspension, and the release fitting model followed the Ritger-Peppas and Weibull models. The effective concentration of the nanoemulsion was evaluated in vivo using a Wistar rat model, and the area under the plasma concentration-time curve of the buckwheat flavonoids nanoemulsion was 2.2-fold higher than that of the buckwheat flavonoid suspension. The Cmax of the nanoemulsion was 2.6-fold greater than that of the suspension. These results indicate that the nanoemulsion is a promising oral drug delivery system that can improve the oral bioavailability to satisfy the clinical requirements.

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: Papp 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.

In Vitro Testing of Sunscreens for Dermal Absorption: A Platform for Product Selection for Maximal Usage Clinical Trials.

Sunscreen products contain UV filters as active ingredients for the protection of the skin against UVR. The US Food and Drug Administration (FDA) issued a new proposed rule in 2019 (84.FR.6204) for sunscreens and identified the need for additional safety data for certain UV filters including their dermal absorption data. Dermal absorption data reveal systemic exposure of UV filters in humans, which can be obtained from clinical maximal usage trials. FDA guidance recommends conducting in vitro skin permeation tests (IVPTs) to help select formulations for maximal usage clinical trials as IVPT results may be indicative of in vivo absorption. This case study reports in vitro methodologies used for the selection of sunscreen products for an FDA-sponsored proof-of-concept maximal usage clinical trial. An IVPT method was developed using human cadaver skin. Commercially available sunscreen products were tested to determine the skin absorption potential of common UV filters using the IVPT. All the studied sunscreen products demonstrated a certain degree of skin absorption of UV filters using IVPT, and a formulation rank order was obtained. These sunscreen products were also characterized for several formulation properties including the globule size in emulsions, which was found to be an indicator for the rank order.

Engineering of Long-Term Stable Transparent Nanoemulsion Using High-Gravity Rotating Packed Bed for Oral Drug Delivery.

BACKGROUND: Oil-in-water drug nanoemulsion forms drug delivery systems with high oral bioavailability. The conventional fabrication methods of nanoemulsion are low energy emulsification methods and high energy emulsification methods. However, both two methods are not ideal for industrial production. The problem of low energy emulsification methods is the high dosage of surfactant and co-surfactant which has potential biosecurity issues. What is more, high energy emulsification methods have some disadvantages, like the destruction of drug components, the price of equipment and the difficulties of industrial production. Hence, there have been a few commercial drug nanoemulsions so far. METHODS: In this work, we reported a novel method for the fabrication of stable and transparent drug nanoemulsion which contains hydrophilic drug rosuvastatin (ROS) calcium or hydrophobic drug silybinin (SYN) by using high-gravity rotating packed bed (RPB). The drug nanoemulsion was systematically characterized by droplet size, size distribution, stability and in vitro drug release as well as Caco-2 cells permeability. RESULTS: Compared with the self-emulsification method (SE), high-gravity technology could reduce 75% amount of mixed surfactants. The as-prepared nanoemulsion exhibited a very narrow droplet size distribution with a size of 13.53 ± 0.53 nm and a polydispersity index of 0.073 ± 0.018. Meanwhile, the drug nanoemulsion was physicochemically stable at 25°C and 4°C for one-year storage. Furthermore, both ROS and SYN nanoemulsion displayed higher cell permeability and in vitro dissolution than that of commercial formulations. CONCLUSION: These results demonstrate that RPB can be a potential device to facilitate the industrial production of drug nanoemulsion.

Time-of-flight resolved light field fluctuations reveal deep human tissue physiology.

Red blood cells (RBCs) transport oxygen to tissues and remove carbon dioxide. Diffuse optical flowmetry (DOF) assesses deep tissue RBC dynamics by measuring coherent fluctuations of multiply scattered near-infrared light intensity. While classical DOF measurements empirically correlate with blood flow, they remain far-removed from light scattering physics and difficult to interpret in layered media. To advance DOF measurements closer to the physics, here we introduce an interferometric technique, surmounting challenges of bulk motion to apply it in awake humans. We reveal two measurement dimensions: optical phase, and time-of-flight (TOF), the latter with 22 picosecond resolution. With this multidimensional data, we directly confirm the unordered, or Brownian, nature of optically probed RBC dynamics typically assumed in classical DOF. We illustrate how incorrect absorption assumptions, anisotropic RBC scattering, and layered tissues may confound classical DOF. By comparison, our direct method enables accurate and comprehensive assessment of blood flow dynamics in humans.

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.

Distribution of benzalkonium chloride into the aqueous phases of submicron dispersed systems: emulsions, aqueous lecithin dispersion and nanospheres.

Partitioning of benzalkonium chloride (BAC) into the aqueous phases of submicron dispersed systems such as submicron emulsions, aqueous lecithin dispersion (WLD), and suspension of nanospheres (NLC) was studied. The aqueous phases of the investigated systems were obtained by ultracentrifugation and subsequently were subjected to ultrafiltration, which procedure allowed distinguishing between the fractions of free benzalkonium chloride (w) and those incorporated in the liposomal and micellar region (wlm). The fractions present in the oily phase and in the interphase of submicron emulsions were calculated. Despite the various composition of the investigated formulations and the initial concentration of BAC, w values were very small at 0.2-8.0%. The wlm value in submicron emulsions was increased by increasing the total concentration of preservative from 29.0 to 42.0%. Using polysorbate 80 instead of lecithin resulted in a distribution of BAC to aqueous-liposomal-micellar phase that was twice as high. The very low concentration of antimicrobial active form of benzalkonium chloride was analyzed in the aqueous phase of emulsions stabilized with lecithin as well as in aqueous lecithin dispersion and nanospheres (below 3%). Replacement of lecithin with polysorbate 80 in emulsions with polysorbate significantly increase (up to 8%) the fraction of benzalkonium chloride in the aqueous phase where microbial growth occurs.

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.

Formulation, characterization and in vitro evaluation of antifungal activity of Nystatin micro emulsion for topical application.

The current research aims at development and assessment of o/w nystatin microemulsion. The pseudoternary phase diagrams were developed to determine microemulsion existence regions by water titration method. Nystatin was liquefied in the blend of oil phase, surfactant and cosurfactant. Microemulsion was made by deliberate mixing of water and stirring in this blend. The S-mix (surfactant-cosurfactant mixtures) of the ratio 1:2 was found better than 1:1 and 2:1 S-mix ratios. In vitro permeation studies by Franz diffusion cell revealed faster rate of nystatin release from such microemulsion (5.37µg/cm2/h) as compared to nystrin (4.79µg/cm2/h), a commercially available aqueous suspension. Kinetic modeling demonstrated zero order drug release and release mechanism found to be anomalous i.e. superposition of dispersion and swelling controlled drug release. Antifungal activity was performed using well diffusion method in vitro against Candida albicans cultures grown on Sabouraud's dextrose agar. The results also confirmed the high diffusion rate of drug from microemulsion as compared to aqueous suspension. The outcomes of this study propose that topical microemulsion of nystatin provides better antifungal activity as compared to emulsion gels or aqueous suspensions.

Preparation, Optimization, and Evaluation of Hyaluronic Acid-Based Hydrogel Loaded with Miconazole Self-Nanoemulsion for the Treatment of Oral Thrush.

Miconazole nitrate (MZ) is a BCS class II antifungal poorly water-soluble drug with limited dissolution properties and gastrointestinal side effects. Self-nanoemulsifying delivery system-based gel of MZ can improve both solubility and oral mucosal absorption with enhanced antifungal activity. The study aims to formulate MZ self-nanoemulsion (MZ-NE) and combine it within hyaluronic acid-based gel. MZ solubility in various oils, surfactants, and cosurfactant used in NE formulations were evaluated. Mixture design was implemented to optimize the levels of NE components as a formulation variable to study their effects on the mean globule size and antifungal inhibition zones. Further, the optimized MZ-NE was loaded into a hyaluronic acid gel base. Rheological behavior of the prepared gel was assessed. Ex vivo permeability of optimized formulation across buccal mucous of sheep and inhibition against Candida albicans were examined. Mixture design was used to optimize the composition of MZ-NE formulation as 22, 67, and 10% for clove oil, Labrasol, and propylene glycol, respectively. The optimized formulation indicated globule size of 113 nm with 29 mm inhibition zone. Pseudoplastic flow with thixotropic behavior was observed, which is desirable for oral gels. The optimized formulation exhibited higher ex vivo skin permeability and enhanced antifungal activity by 1.85 and 2.179, respectively, compared to MZ-SNEDDS, and by 1.52 and 1.72 folds, respectively, compared to marketed gel. Optimized MZ-NE hyaluronic acid-based oral gel demonstrated better antifungal activity, indicating its potential in oral thrush pharmacotherapy.

Synergistic interaction between exogenous and endogenous emulsifiers and its impact on in vitro digestion of lipid in crowded medium.

Control of lipid digestibility by various food components has received great attention in recent decades. However, there is limited literature on investigating the synergistic effect of exogenous emulsifiers and endogenous sodium cholate (SC) on lipid digestion in a simulated physiological crowded medium. In this work, the synergistic interaction of Tween80 and SC according to the regular solution theory, and the hydrolysis of lipid emulsions containing tricaprylin, glyceryltrioleate or soybean oil in crowding medium was studied. The results show that emulsions stabilized by a combination of Tween80 and SC showed higher digestion rate and transformation than those with Tween80 or SC. The digestion rate could be increased by polyethylene glycols (PEGn) with varying crowding degree. The denaturation temperature of the lipase was increased in macromolecular crowded medium. This work allows for better understanding of the interaction between the amphiphiles and the macromolecular crowding effect on lipase digestion in the physiological environment.

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.

Preparation and Pharmacokinetics Evaluation of Solid Self-Microemulsifying Drug Delivery System (S-SMEDDS) of Osthole.

The study was performed aiming to enhance the solubility and oral bioavailability of poorly water-soluble drug osthole by formulating solid self-microemulsifying drug delivery system (S-SMEDDS) via spherical crystallization technique. Firstly, the liquid self-microemulsifying drug delivery system (L-SMEDDS) of osthole was formulated with castor oil, Cremophor RH40, and 1,2-propylene glycol after screening various lipids and emulsifiers. The type and amount of polymeric materials, good solvents, bridging agents, and poor solvents in S-SMEDDS formulations were further determined by single-factor study. The optimal formulation contained 1:2 of ethyl cellulose (EC) and Eudragit S100, which served as matrix forming and enteric coating polymers respectively. Anhydrous ethanol and dichloromethane with a ratio of 5:3 are required to perform as good solvent and bridging agent, respectively, with the addition of 0.08% SDS aqueous solution as poor solvent. The optimized osthole S-SMEDDS had a high yield (83.91 ± 3.31%) and encapsulation efficiency (78.39 ± 2.25%). Secondly, osthole L-SMEDDS was solidified to osthole S-SMEDDS with no significant changes in terms of morphology, particle size, and zeta potential. In vitro release study demonstrated a sustained release of the drug from osthole S-SMEDDS. Moreover, in vivo pharmacokinetic study showed that the Tmax and mean residence time (MRT(0-t)) of osthole were significantly prolonged and further confirmed that osthole S-SMEDDS exhibited sustained release effect in rabbits. Comparing with osthole aqueous suspension and L-SMEDDS, osthole S-SMEDDS increased bioavailability by 205 and 152%, respectively. The results suggested that S-SMEDDS was an effective oral solid dosage form, which can improve the solubility and oral bioavailability of poorly water-soluble drug osthole.

Determination of oral bioavailability of curcuminoid dispersions and nanoemulsions prepared from Curcuma longa Linnaeus.

BACKGROUND: Curcuminoid from Curcuma longa Linnaeus has been demonstrated to be effective in anti-cancer and anti-inflammation. The objectives of the present study were to prepare curcuminoid dispersion and nanoemulsion from C. longa and determine their oral bioavailabilities in rats. RESULTS: After curcuminoid extraction using 99.5% ethanol, bisdemethoxycurcumin (BDMC), demethoxycurcumin (DMC) and curcumin were separated within 10 min by high-performance liquid chromatography using an Eclipse XDB-C18 column (Agilent, Palo Alto, CA, USA) and a gradient mobile phase of 0.1% aqueous formic acid and acetonitrile, with a flow rate of 1 mL min-1 , column temperature of 35 °C and detection wavelength of 425 nm. Curcuminoid nanoemulsion at a particle size of 12.1 nm and encapsulation efficiency 98.8% was prepared using lecithin, Tween 80 and water. A pharmacokinetic study in rats revealed that the parameters including Tmax , Cmax , t1/2 and the area under the curve were higher for curcuminoid nanoemulsions than for curcuminoid dispersion at the same dose employed for gavage administration, whereas, for intravenous injection, an opposite trend was shown. The oral bioavailabilities of BDMC, DMC, curcumin and total curcuminoids in nanoemulsion and dispersion were 34.39 and 4.65%, 39.93 and 5.49%, 47.82 and 9.38%, and 46 and 8.7%, respectively. CONCLUSION: The results of the present study demonstrate a higher oral bioavailability after incorporation of curcuminoid into nanoemulsion, facilitating its application as a botanic drug. © 2017 Society of Chemical Industry.

A comparison study between lycobetaine-loaded nanoemulsion and liposome using nRGD as therapeutic adjuvant for lung cancer therapy.

To achieve tumor-selective drug delivery, various nanocarriers have been explored using either passive or active targeting strategies. Despite the great number of studies published annually in the field, only nanocarriers using approved excipients reach the clinical stage. In our study, two classic nanoscale formulations, nanoemulsion (NE) and liposome (Lipo) were selected for the encapsulation of lycobetaine (LBT). To improve the lipid solubility of LBT, oleic acid (OA) was used to complex (LBT-OA) with lycobetaine (LBT). Besides, PEGylated lecithin was used to enhance the circulation time. The release behaviors of LBT from non-PEGylated and PEGylated NE and Lipo were compared. PEGylated LBT-OA loaded Lipo (LBT-OA-PEG-Lipo) exhibited a sustained release rate pattern, and in vivo pharmacokinetic profiles showed the extended circulation compared nanoemlusions. Besides, LBT-OA-PEG-Lipo showed an enhanced anti-tumor effect in the mice xenograft lung carcinoma model. Moreover, a multi-target peptide nRGD was co-administered as a therapeutic adjuvant with LBT-OA loaded formulations, which demonstrated improved tumor penetration and enhanced extravasation of formulations. Also, co-administration of nRGD significantly improved the in vivo antitumor efficacy of different formulations, likely due to the depletion of tumor-associated macrophages (TAMs). Thus, LBT-OA-PEG-Lipo+nRGD may represent a promising strategy for cancer chemotherapy against lung carcinoma.

Fabrication and Optimization of Self-Microemulsions to Improve the Oral Bioavailability of Total Flavones of Hippophaë rhamnoides L.

The purpose of this work was to improve the oral bioavailability of a poorly soluble functional food ingredient, the total flavones of Hippophaë rhamnoides L. (TFH). A self-microemulsion drug delivery system (SMEDDS) was developed to overcome the problems of poor absorption of TFH in vivo. The optimal SMEDDS significantly enhanced the solubility of TFH up to 530 times compared to that in water. The mean droplet size was 61.76 nm with uniform distribution. And the loaded system was stable at 25 °C for 3 mo with transparent appearance. The in vitro release of TFH from SMEDDS was faster and more complete than that from suspension. After oral administration of TFH-SMEDDS in rats, the relative bioavailability of TFH was dramatically improved for 3.09 times compared with the unencapsulated form. The investigation indicated the potential application of SMEDDS as a vehicle to improve the oral bioavailability of TFH. PRACTICAL APPLICATION: The lipid-based nanotechnology, namely self-microemulsion drug delivery system (SMEDDS) was used to improve the bioavailability and oral delivery of total flavones of Hippophaë rhamnoides L. (TFH). The relevant bioavailability of TFH could be remarkably 3-fold improved by the optimized SMEDDS. The SMEDDS produced via a simple one-step process for poorly soluble TFH to achieve a significant improvement in the bioavailability, may endorse the promising utilization of TFH in functional foods as well as pharmaceutical fields with an enhanced absorption in vivo.