Title:Formulation and Characterisation of Cilnidipine Microsponge Loaded
Hydrogels for Antihypertensive Activity
Volume: 13
Issue: 1
Author(s): Shreya Shirodkar and Raghuvir Pissurlenkar*
Affiliation:
- Department of Pharmaceutical Chemistry, Goa College of Pharmacy, Panaji, Goa, 403001, India
Keywords:
Microsponge, cilnidipine, topical delivery, antihypertensive, sustained release, drug permeation, skin irritation, in vitro studies.
Abstract:
Background: Owing to presystemic metabolism following oral drug delivery, most antihypertensive
medications have a low bioavailability. Cilnidipine is a calcium channel blocker used
to treat mild to moderate hypertension. Cilnidipine's bioavailability is reduced by 13% due to substantial
presystemic metabolism.
Objective: The study aimed to fabricate non-irritant and stable microsponge-based hydrogel to enhance
the bioavailability of cilnidipine, a weakly water-soluble medication. In addition, the goal
was to enhance the permeation rate and retention time at the site of application.
Methods: Formulation was developed by using a two-level factorial design with Design Expert
software version 13 (14-day free trial). Microsponges were formulated by the emulsion solvent diffusion
method, followed by evaluating responses, such as particle size, percentage entrapment efficiency,
in vitro drug release, and surface morphology. In addition, X-ray diffraction (XRD) and fourier
transform infrared spectroscopy (FT-IR) were performed. Viscosity, swelling behaviour,
spreadability, in vitro diffusion, skin irritancy using Wistar albino rats, and in vitro permeation using
goat skin were assessed, and stability studies were performed after incorporating the finest formulation
into the gel base.
Results: Fabricated microsponges were found to be within the required micro dimensions having
the necessary porous morphology as demonstrated by scanning electron microscopy studies. Drug
entrapment efficiency was found to be in the range of 75-88%. The extended medicament release
duration of up to 8 hours was observed. The diffusion data showed controlled release, as demonstrated
by Higuchi’s plot. In vitro permeation studies displayed enhanced medicament retention and
permeation rate at the site of application.
Conclusion: The fabricated microsponge drug delivery system was found to be stable, non-irritant,
and having enhanced permeation rate and retention time.