Hydrogel thickened microemulsion; a local cargo for the CO- delivery of cinnamaldehyde and berberine to treat acne vulgaris

ABSTRACT For the existence in an advancing world of antibiotics, bacteria struggle and make necessary changes at genetic level. This study was designed to deliver a combination of cinnamaldehyde (CA) and berberine chloride (BER) for the treatment of Propionibacterium acnes induced acne vulgaris. CA and BER were first loaded in a clove oil-based microemulsion and then the resultant microemulsion was converted into a hydrogel system using Carbopol 940. Selection of an appropriate concentration of Carbopol 940 was done based on the visual assessment and viscosity of developed formulations. Different concentration of CA and BER was ensured in CA-BER-ME-Gel and labelled them as F-1, F-2, and F-3. F-1 contained 0.5 %w/w CA and 0.108 %w/w BER. F-2 contained 0.75 %w/w CA and 0.162 %w/w BER. F-3 was composed of 1 %w/w CA and 0.217 %w/w BER. The % cumulative amount of drug permeated from F-1, F-2, and F-3 were found to be 62.16 ± 3.06 %, 64.9 ± 2.85 % and 68.34 ± 4% respectively after 8 h. The CA and BER loaded suspension gel showed significantly lesser permeation profile (27.14 ± 2.42 %) as compared to F-1, F-2 and F-3. The anti-acne potential of F-1, F-2, F-3 and Standard (1% w/w Clindamycin Phosphate gel) in terms of % change in ear thickness was found to be 115 ± 7.27 %, 55.18 ± 12.76 %, 41.85 ± 8.83 % and 30.18 ± 13.94 % respectively. These values were significantly better (p