Optimized Nanoemulsion Formulation Research Articles

Self-nanoemulsifying drug delivery system of persimmon leaf extract: Optimization and bioavailability studies

In current study, a self-nanoemulsifying drug delivery system (SNEDDS) of persimmon ( Diospyros kaki) leaf extract (PLE) was developed and characterized to compare its in vitro dissolution and relative bioavailability with commercially available tablets (Naoxinqing tablets). Pseudo-ternary phase diagrams were constructed by phase diagram by micro plate dilution (PDMPD) method, of which the evaluation method was improved to use Multiskan Ascent for identifying turbidity. The formulation of PLE-loaded SNEDDS was optimized by an extreme vertices experimental design. The optimized nanoemulsion formulation, loading with 44.48 mg/g PLE total flavonoids, consisted of Cremophor EL, Transcutol P, Labrafil M 1944 CS (56:34:10, w/w), and it remained stable after storing at 40 °C, 25 °C, 4 °C for at least 6 months. When diluted with water, the SNEDDS droplet size was 34.85 nm and the zeta potential was −6.18 mV. Compared with the commercial tablets, the AUC of both quercetin and kaempferol, which are representative active flavonoids of PLE, was increased by 1.5-fold and 1.6-fold respectively following oral administration of PLE-loaded SNEDDS in fasting beagle dogs. These results indicate that SNEDDS is a promising drug delivery system for increasing the oral bioavailability of PLE.

Oil based nanocarrier for improved oral delivery of silymarin: In vitro and in vivo studies

Silymarin, obtained from Silybum marianum is used for hepatoprotection and having poor aqueous solubility and low bioavailability. Therefore, it was thought to incorporate the drug into oil-in-water (o/w) based nanocarrier to increase its oral bioavailability. In the present study, o/w nanocarrier was prepared by titration method and was characterized for droplet size, viscosity, etc. In vitro drug release was carried out by dialysis membrane method. A pharmacokinetic study was performed to determine maximum plasma concentration ( C max), area under the curve (AUC), etc. and hepatoprotective activity was evaluated in terms of serum enzyme estimation. The optimized nanoemulsion formulation consisted of sefsol-218 as oil, tween 80 as a surfactant and ethanol as a co-surfactant having nano-droplet size and low viscosity. In vitro dissolution studies showed higher drug release from nanoemulsion as compared to bulk drug suspension. The AUC and C max of nanoemulsion after oral administration were 4-fold and 6-fold higher than those of drug suspension of silymarin. The results of pharmacokinetic studies showed better effects of developed nanoemulsion than drug suspension and marketed formulation. The present study showed that the nanoemulsion being a versatile technology has the potential to improve the biopharmaceutics properties of silymarin.

Formulation Design of Indomethacin-Loaded Nanoemulsion For Transdermal Delivery

The aim of the present study was to investigate the potential of nanoemulsion formulations for transdermal delivery of indomethacin (IND). Nanoemulsions formulations with different Surfactant: co surfactant ratios (S mix); F1-F6 (1:1, 2:2, 3:1, 4:1, 1:2 and 3:2) were prepared by the spontaneous emulsification method, and characterized for morphology using transmission electron microscopy (TEM), droplet size, and rheological characteristics. The ex vivo skin permeation studies were performed using Franz diffusion cell with rabbit skin as permeation membrane. A significant increase in the permeability parameters such as steady-state flux (Jss), permeability coefficient (Kp), and enhancement ratio (Er) was observed in nanoemulsion formulations compared with the conventional IND gel. The anti-inflammatory effects of nanoemulsion formulations showed a significant increase in percent inhibition value after 4 hours when compared with conventional IND gel on carrageenan-induced paw edema in rats. Significant increase in permeability parameters was observed in nanoemulsion formulations (P< 0.05). The steady-state flux (Jss) and permeability coefficient (Kp) for optimized nanoemulsion formulation (F1, 1:1 S mix were found to be 22.61±3.45 μg/ cm2/h and 0.22x10− 2 ±0.0003 cm/h, respectively), which were significant compared with conventional IND gel and (P< 0.001). Enhancement ratio (Er) was found to be 8.939 in optimized formulation F1 compared with IND gel. These results suggested that nanoemulsions can be used as potential vehicles for improved transdermal delivery of indomethacin as an approach to eliminate the side effect of the oral dose.

Design and Development of Oral Oil-in-Water Nanoemulsion Formulation Bearing Atorvastatin: In Vitro Assessment

The objective of the present investigation was to design a thermodynamically stable and dilutable nanoemulsion formulation of AT-Ca with minimum surfactant concentration that could improve its solubility as well as its oral bioavailability. The composition of optimized nanoemulsion formulation was Sefsol 218 and oleic acid (1:1) 10% w/w, as an oil phase, Tween-20 (19% w/w) as a surfactant, Carbitol (19% w/w) as a cosurfactant and distilled water (52% w/w) as an aqueous phase, containing 10 mg of AT. The optimized formulation showed higher% drug release (99.34%), lower droplet size (42.8 ± 0.42 nm) with low polydispersity index (0.237 ± 0.012), less viscosity (27.51 ± 1.01 cP) and infinite dilution capability. In vitro drug release from the nanoemulsion formulations was highly significant (p < 0.01) as compared to drug suspension.

Transdermal delivery of anticancer drug caffeine from water-in-oil nanoemulsions

Recently caffeine has been investigated for the treatment of various types of cancers upon oral administration. There is also some evidence that dermally applied caffeine can protect the skin from skin cancer caused by sun exposure. Therefore nanoemulsion formulation of caffeine for transdermal drug delivery was developed and evaluated in the present investigation. Different w/o nanoemulsion formulations of caffeine were prepared by oil phase titration method. Thermodynamically stable nanoemulsions were characterized for morphology, droplet size, viscosity and refractive index. The in vitro skin permeation studies were performed on Franz diffusion cell using rat skin as permeation membrane. The in vitro skin permeation profile of optimized formulation was compared with aqueous solution of caffeine. Significant increase in permeability parameters was observed in nanoemulsion formulations ( P < 0.05) as compared to aqueous solution of caffeine. The steady-state flux ( J ss) and permeability coefficient ( K p) for optimized nanoemulsion formulation (C12) were found to be 147.55 ± 8.21 μg/cm 2/h and 1.475 × 10 −2 ± 0.031 × 10 −2 cm/h, respectively. Enhancement ratio ( E r) was found to be 17.37 in optimized formulation C12 compared with other formulations. Overall these results suggested that w/o nanoemulsions are good carriers for transdermal delivery of caffeine.

Investigation of true nanoemulsions for transdermal potential of indomethacin: characterization, rheological characteristics, and ex vivo skin permeation studies

The aim of the present study was to investigate the potential of true nanoemulsions for transdermal delivery of indomethacin. Thermodynamically stable true nanoemulsions were characterized for morphology using transmission electron microscopy (TEM), droplet size, rheological characteristics, and refractive index. The rheological behavior for all true nanoemulsions was found to be Newtonian as viscosity was unchanged by increasing the rate of shear. The ex vivo skin permeation studies were performed using Franz diffusion cell with rat skin as permeation membrane. The ex vivo skin permeation profile of optimized formulation was compared with marketed Indobene gel and nanoemulsion gel. Significant increase in permeability parameters was observed in nanoemulsion formulations (P < 0.05). The steady-state flux (Jss) and permeability coefficient (Kp) for optimized nanoemulsion formulation were found to be 73.96 ± 2.89 μg/cm2/h and 1.479 × 10−2 ± 0.289 × 10− 2 cm/h, respectively, which were significant compared with Indobene gel and nanoemulsion gel (P < 0.05). Enhancement ratio (Er) was found to be 7.88 in optimized formulation F6 compared with other formulations. These results suggested that nanoemulsions can be used as potential vehicles for improved transdermal delivery of indomethacin.

Accelerated stability testing of celecoxib nanoemulsion containing Cremophor-EL

Celecoxib (CXB), a selective cyclooxygenase-2 inhibitor has been recommended for the treatment of arthritis and osteoarthritis upon oral administration. However, long term oral administration of celecoxib cause serious gastrointestinal adverse effects. Therefore the aim of the present study was to enhance CXB’s physical and chemical stability using nanoemulsion formulation in order to eliminate gastrointestinal adverse effects of its oral administration. Optimized nanoemulsion formulation was prepared by spontaneous emulsification method. Nanoemulsion was characterized by droplet size, viscosity and refractive index. Stability studies were performed for the period of 3 months. Droplet size, viscosity and refractive index were determined every month. Shelf-life of nanoemulsion formulation was also determined by accelerated stability testing. It was found that droplet size, viscosity and refractive index were slightly increased at refrigerator and room temperature in 3 months period. However, the changes in these parameters were not statistically significant (p ≥ 0.05). The shelf-life of optimized nanoemulsion formulation was found to be 2.38 years at room temperature. These results indicated that both physical as well as chemical stability of celecoxib can be enhanced in nanoemulsion formulation using Cremophor-EL as surfactant. Key words: Nanoemulsion, celecoxib, shelf life, cremophor-EL.

Nanoemulsions as vehicles for transdermal delivery of aceclofenac.

The aim of the present study was to investigate the potential of a nanoemulsion formulation for transdermal delivery of aceclofenac. Various oil-in-water nanoemulsions were prepared by the spontaneous emulsification method. The nanoemulsion area was identified by constructing pseudoternary phase diagrams. The prepared nanoemulsions were subjected to different thermodynamic stability tests. The nanoemulsion formulations that passed thermodynamic stability tests were characterized for viscosity, droplet size, transmission electron microscopy, and refractive index. Transdermal permeation of aceclofenac through rat abdominal skin was determined by Franz diffusion cell. The in vitro skin permeation profile of optimized formulations was compared with that of aceclofenac conventional gel and nanoemulsion gel. A significant increase in permeability parameters such as steady-state flux (J(ss)), permeability coefficient (K(p)), and enhancement ratio (E(r)) was observed in optimized nanoemulsion formulation F1, which consisted of 2% wt/wt of aceclofenac, 10% wt/wt of Labrafil, 5% wt/wt of Triacetin, 35.33% wt/wt of Tween 80, 17.66% wt/wt of Transcutol P, and 32% wt/wt of distilled water. The anti-inflammatory effects of formulation F1 showed a significant increase (P < .05) in percent inhibition value after 24 hours when compared with aceclofenac conventional gel and nanoemulsion gel on carrageenan-induced paw edema in rats. These results suggested that nanoemulsions are potential vehicles for improved transdermal delivery of aceclofenac.