Fig 1.
Chemical scheme of synthetic pathways for synthesis of PEG-CUR (Step 1), formulation of PEG-CUR loaded ointment with Cremophore (Step 2).
Fig 2.
Phase solubility diagram of CUR in different molar concentrations of PEG 6000 and molar concentration of CUR showed that 3:1 PEG-CUR complex has maximum solubility of CUR represented as mean ± SD (n = 3).
Table 1.
Calculation of Gibbs free energy of curcumin.
Fig 3.
Comparative evaluation of effect of CUR and PEG-CUR (A) on solubility (B, C) antibacterial effect and (D) Cremophore as permeation enhancer for selection of ointment formulations.
Table 2.
Preparation of CUR and CUR-PEG ointments with oleaginous bases mineral oil (2.54 w/v) and white soft paraffin (6.44 w/v) in each formulation.
Fig 4.
FTIR-spectra of pure curcumin, PEG-Curcumin, PEG, PEG-CUR Ointment and PEG-CUR Ointment with cremophore.
Fig 5.
CUR absorption studies from ophthalmic mucous by using Transwell cells (A) and comparative ex-vivo mucous permeation of CUR-3 (■), PEG-CUR3 () PEG-CUR-C6 (
) ointment formulations via transwell plates at 150 rpm after 4 h of experiment.
Data is shown as mean ±SD (n = 3).
Fig 6.
Drug diffusion study of CUR-3 (■), PEG-CUR3 () PEG-CUR-C6 (
) ointment formulations via ussing cell (A) at 37°C. Graph in (B) showed increase in percentage permeability of PEG-CUR-C6 as compared to the Cur and PEG-CUR ointments across corneal membrane. Data is shown as mean ±SD (n = 3).
Fig 7.
Represents Caco-2 cell viability after 3h (black bar) and 24 h (grey bar) of incubation at 37°C of pure Curcumin, CUR-C6, PEG-Curcumin, PEG-CUR-C6 (0.5% and 1% w/v each) as compared to 2% triton X-100 (negative control) and MEM (positive control).
Data is shown as mean±SD (n = 3).
Fig 8.
Antimicrobial activity of ciprofloxacin (standard), curcumin, PEG-curcumin, CUR-3, CUR-C6, PEG-CUR3, PEG-CUR-C6 ointments in various concentration shown in (A) against (■) Staphylococcus aureus () Pseudomonas aeruginosa and graph shown in (B).
Test was performed in triplicate mean ± SD (n = 3).