Formulation Designing and Optimization of Loteprednol-loaded spanlastic Nanocarriers for Treatment of Ocular Inflammation

Abstract

Objective: The objective of this scientific work was focused on formulation, optimization and evaluation of
loteprednol-loaded spanlastic nanocarriers for effective treatment of ocular inflammation with enhanced
transcorneal drug permeation, prolonged corneal residence time, and sustained drug release profile.
Materials and Methods: The spanlastic nanocarriers of loteprednol was prepared by ethanol injection method
using Span 60 and Tween 80 as vesicular components. A 23 factorial design was employed in the optimization studies
selecting independent variables such as Span 60, Tween 80, and drug content, whereas, the response variables such
as particle size, polydispersity index, zeta potential, entrapment efficiency, and cumulative % drug release. The
optimized formulation was evaluated for various in vitro and ex vivo parameters. Results and Discussion: The
optimized formulation of spanlastic nanocarriers of loteprednol was found to have 207.4 nm particle size, 0.41
polydispersity index, −0.62 mV zeta potential, and 58.23% entrapment efficiency. The cumulative % drug release
was 98.45% during 8-h period exhibiting sustained release and Korsmeyer-Peppas model release kinetics. The
ex vivo drug permeation study across goat eye cornea exhibited apparent permeability (Papp) of 11.95 cm/min-1
and steady-state flux (Jss)of 19.45 mg/cm2 min-1which was >5 times higher than marketed product. The developed
formulation maintained its physical characteristics and possessed all desired product quality attributes in the
ideal range. Conclusion: The developed loteprednol loaded spanlastic nanocarriers demonstrated all the quality
parameters very close to the software predicted values and also exhibited enhanced transcorneal drug permeation
which would lead to higher ocular drug bioavailability and need of less frequent drug administration in effective
management of ocular inflammation.