Simvastatin (SVA) is a well-prescribed drug for treating cardiovascular and hypercholesterolemia. Due to the extensive hepatic first-pass metabolism and poor solubility, its oral bioavailability is 5%. Solid lipid nanoparticles (SLNs) and hydrogel-coated SLNs were investigated to overcome the limited bioavailability of SVA. Four different lipids used alone or in combination with two stabilizers were employed to generate 13 SLNs. Two concentrations of chitosan (CS) and alginate (AL) were coating materials. SLNs were studied for particle size, zeta potential, in vitro release, rheology, and bioavailability. The viscosities of both the bare and coated SLNs exhibited shear-thinning behavior. The viscosity of F11 (Chitosan 1%) at 20 and 40 rpm were 424 and 168 cp, respectively. F11 had a particle size of 260.1 ± 3.72 nm with a higher release; the particle size of F11-CS at 1% was 524.3 ± 80.31 nm. In vivo studies illustrated that F11 had the highest plasma concentration when compared with the SVA suspension and coated chitosan (F11 (Chitosan 1%)). Greater bioavailability is measured as (AUC0→24), as compared to uncoated ones. The AUC for F11, F11-CS 1%, and the SVA suspension were 1880.4, 3562.18, and 272 ng·h/mL, respectively. Both bare and coated SLNs exhibited a significantly higher relative bioavailability when compared to that from the control SVA.

The present work reports the development, optimization and characterization of novel lipid based nanoformulations viz., Liquid crystalline nanoparticles (LCNP), solid lipid nanoparticles (SLN) and nanostructured lipid carriers (NLC) and liposomes loaded with Tacrolimus (Tac) for topical delivery. Different nanoformulations were developed after screening lipids and suitable surfactants depending upon emulsification ability. The various nanoformulations were then optimized (to achieve higher entrapment efficacy, lower particle size, PDI and zeta potential), characterized and loaded into gel. The gels loaded with nanoformulations were also characterized depending upon rheology and viscosity. The gels were analyzed for in vitro drug release, HaCaT cell lines studies and skin permeation studies. The in vivo efficacy studies were carried out using mouse tail model and skin irritation studies using Draize patch test and measurement of TEWL. The developed nanoformulations showed optimum particle size (<200 nm), polydispersity index (PDI < 0.3), zeta potential (≥-10 mV) and higher entrapment efficiency (>85%). The nanoformulations showed higher penetration of Tac into skin. Tac-LCNP, Tac-SLN, Tac-NLC and Tac-liposomes loaded gels showed 14, 11.5, 12.5 and 3.7 folds increment in dermal bioavailability respectively, in comparison to free Tac loaded gel and 2.5, 2 and ∼2 folds augmentation in dermal bioavailability respectively as compared to Tacroz™ Forte. In case of Tac-liposomes, the dermal bioavailability was lower as compared with the marketed formulation, Tacroz™ Forte. Despite, the increased bioavailability into the skin, the developed nanoformulations showed no significant skin irritation. The above mentioned nanoformulations were able to achieve greater penetration of Tac into the skin as compared to marketed ointment of Tac, Tacroz™ Forte.

This study aims at developing an optimised nanostructured lipid carrier (NLC) of lycopene for efficient absorption following oral administration. The optimised formulation showed an average particle size of 121.9 ± 3.66 nm, polydispersity index (PDI) 0.370 ± 0.97 and zeta potential -29.0 ± 0.83 mV. Encapsulation Efficiency (% EE) and drug loading (% DL) was found to be 84.50% ± 4.38 and 9.54% ± 2.65, respectively. In vitro release studies demonstrated the burst release within 4-9 h followed by sustained release over 48 h. The IC50 value of lycopene extract and optimised NLC for ABTS+• were found to be 172.37 μg Trolox equivalent and 184.17 μg Trolox equivalent whereas, for DPPH•, 117.76 μg Trolox equivalent and 143.08 μg Trolox equivalent respectively. Ex vivo studies and MTT assay revealed that the NLC had better permeation and cause sufficiently more cytotoxicity as compared to drug extract due to higher bioavailability and greater penetration.