Development of carvedilol-loaded transfersomes for intranasal administration to overcome poor nasal permeability and hepatic first pass effect so as to enhance its bioavailability. The purpose of this study was to develop carvedilol-loaded transfersomes containing different edge activators (EAs) then evaluating the in vivo behavior of the optimized formula in rabbits. The vesicles were prepared by incorporating different EAs including Span 20, Span 60, Tween 20, Tween 80, and sodium deoxycholate (SDC) in the lipid bilayer and each EA was used in three different ratios with respect to phosphatidylcholine (PC) including 95:5%, 85:15%, and 75:25% w/w (PC:EA). Evaluation of transfersomes was carried out in terms of shape, size, entrapment efficiency (EE), in vitro release, ex vivo permeation, confocal laser scanning microscopy (CLSM), and stability studies. The pharmacokinetic study of the optimized formula was conducted in rabbits. The mean diameter of the vesicles was in the range of 295-443 nm. Transfersomes prepared with 95:5% (w/w) (PC:EA) ratio showed highest EE% where Span 60 gave the highest values. Whereas those prepared using 85:15% w/w ratio showed highest percentages of drug release where SDC was superior to other EAs. The developed transfersomes exhibited significantly higher amounts of carvedilol permeated through nasal mucosa. CLSM of formula T14 containing SDC with 85:15% (w/w) (PC:EA) ratio revealed high permeation across the nasal mucosa. The nanotransfersomal vesicles were significantly more efficient in nasal delivery of carvedilol with absolute bioavailability of 63.4%.
Olanzapine (OL) is atypical antipsychotic drug which suffers from an extensive hepatic metabolism and poor bioavailability. In addition, it has low brain permeability due to efflux by P-glycoproteins. In the current investigation, surface modified niosomes containing OL were prepared for brain targeting of drug through nasal route. Spans were mixed with cholesterol at ratios of 1:1, 1:2, 1:3 and 1:4 of cholesterol to surfactant respectively to prepare niosomes. Chitosan (CS) coated vesicles were prepared by mixing optimum niosomal formula with CS solution (0.6%). Physicochemical and stability parameters and confocal laser scanning microscopy (CLSM) of developed vesicles were determined. Also, the brain targeting properties of the optimized formula were measured in rats. Niosomes had Entrapment efficiency (EE %) more than 90% and particle size (PS) ranging from 201.3 ± 2.4 nm to 1446 ± 9 nm. TEM photomicrographs of developed vesicles showed a clear shell surrounding the coated vesicles. The produced vesicles exhibited 2.46 folds increase in the amount of drug that permeated nasal mucosa and prolonged OL release compared to drug solution. Coated niosomes further improved drug permeation. CLSM of coated optimum formula showed high permeation across the nasal mucosa. Stability studies revealed non-significant changes in the physicochemical parameters of optimum formula over the storage period. The optimized nasal CS coated niosomes showed a three folds increase in OL concentration in the brain compared to the intranasal solution of the drug. In conclusion, the developed vesicles were efficient in nasal delivery of OL into the brain.
Carvedilol, a beta-adrenergic blocker, suffers from poor systemic availability (25%) due to first-pass metabolism. The aim of this work was to improve carvedilol bioavailability through developing carvedilol-loaded solid lipid nanoparticles (SLNs) for nasal administration. SLNs were prepared by emulsion/solvent evaporation method. A 23 factorial design was employed with lipid type (Compritol or Precirol), surfactant (1 or 2% w/v poloxamer 188), and co-surfactant (0.25 or 0.5% w/v lecithin) concentrations as independent variables, while entrapment efficiency (EE%), particle size, and amount of carvedilol permeated/unit area in 24 h (Q 24) were the dependent variables. Regression analysis was performed to identify the optimum formulation conditions. The in vivo behavior was evaluated in rabbits comparing the bioavailability of carvedilol after intravenous, nasal, and oral administration. The results revealed high drug EE% ranging from 68 to 87.62%. Carvedilol-loaded SLNs showed a spherical shape with an enriched core drug loading pattern having a particle size in the range of 66 to 352 nm. The developed SLNs exhibited significant high amounts of carvedilol permeated through the nasal mucosa as confirmed by confocal laser scanning microscopy. The in vivo pharmacokinetic study revealed that the absolute bioavailability of the optimized intranasal SLNs (50.63%) was significantly higher than oral carvedilol formulation (24.11%). Hence, we conclude that our developed SLNs represent a promising carrier for the nasal delivery of carvedilol.
1 November 2019 in Drug Delivery and Translational Research
The current study aimed to encapsulate fluvastatin sodium (FVS), a member of the statins family possessing pleiotropic effects in rheumatoid arthritis (RA), into spanlastic nanovesicles (SNVs) for transdermal delivery. This novel delivery could surmount FVS associated oral encumbrances such as apparent first-pass effect, poor bioavailability and short elimination half-life, hence, accomplishing platform for management of RA. To consummate this objective, FVS-loaded SNVs were elaborated by thin film hydration method, utilizing either Span 60 or Span 80, together with Tween 80 or Brij 35 as an edge activator according to full factorial design (24). Applying Design-Expert® software, the influence of formulation variables on SNVs physicochemical properties and the optimized formulation selection were explored. Additionally, the pharmacokinetic studies were scrutinized in rats. Furthermore, in Freund's adjuvant-induced arthritis, rheumatoid markers, TNF-α, IL-10, p38 MAPK, and antioxidant parameters were measured. The optimum SNVs were nano-scaled spherical vesicles (201.54 ± 9.16 nm), having reasonable entrapment efficiency (71.28 ± 2.05%), appropriate release over 8 h (89.45 ± 3.64%) and adequate permeation characteristics across the skin (402.55 ± 27.48 µg/cm2). The pharmacokinetic study disclosed ameliorated bioavailability of the optimum SNVs gel by 2.79- and 4.59-fold as compared to the oral solution as well as the traditional gel, respectively. Moreover, it elicited a significant suppression of p38 MAPK expression and also significant improvement of all other measured biomarkers. Concisely, the foregoing findings proposed that SNVs can be auspicious for augmenting FVS transdermal delivery for management of RA.