ABSTRACT
Objective: To prepare the Lonicerae Japonicae Flos (LJF) extract supramolecular hydrogel and investigate its properties and release behavior in vitro. Methods: The LJF was extracted with 40% ethanol. Taking the content of phenolic acids as the quantitative index, N-(9-fluorenylmethoxycarbonyl)-L-phenylalanine was selected as the gelator to prepare LJF extract supramolecular hydrogels. The release behavior was studied by in vitro release experiment. Results: The addition of LJF extract not only did not affect the formation of supramolecular hydrogel, but also improved the stability of supramolecular hydrogel. The release behavior of LJF extract was related to its loading and pH value of release medium. When the drug loading of LJF extract was 0.5 mg/mL, the cumulative release rate was the highest. Moreover, the cumulative release rate increased with the pH value of the release medium, showing obvious controlled release characteristics. Conclusion: Supramolecular hydrogels as the release carrier for LJF extract have an obvious sustained and controlled release, which provides a new idea for the development and application of LJF in medicine.
ABSTRACT
Objective: The objective of the present investigation was to develop olive and soybean oil-based oleogels with Span 40 and/or Tween 80 (as gelator and/or surfactant) and determine the critical gelator concentration (CGC), characterise and compare the rheological, thermal properties and drug release profile of the gels formed for topical delivery. Methods: Olive and soybean oil-based Span 40 and Span 40/Tween 80 oleogel formulations were prepared by solid fiber mechanism and subjected to organoleptic evaluation, FT-IR spectroscopy, thermal analysis, rheological study, kinetic modeling of gelation and drug release. Results: The critical gelator (Span 40) concentration was found to be lower for olive oil (12% w/v) and depend on the type of oil. Tween 80 reduced CGC of soybean oleogels only. Soybean oil-based oleogel containing 18% w/v Span 40 was found to form more flexible, less viscous and thermally less stable formulation with better release of paracetamol as evident from lower melt flow index, Tg value, lower β and higher α value compared to olive oil-based oleogel with 12% w/v Span 40 (CGC). Surfactant addition can be assumed to modify the microarchitecture of the oleogels to a great extent to produce more flexible and thermally stable gels with even better drug release profile. Span-Tween based soybean oleogel formed a gel-matrix whereas matrix in olive oil-based oleogels containing Span only became slightly flexible to release the drug in zero-order fashion on the addition of surfactant cogelator. Conclusion: Nature of oil exerts profound influence on the rheological, thermal and release profile of oleogels containing Span 40 as gelator and/or Tween 80 as surfactant cogelator.