Development and characterization of PEGylated ofloxacin and ciprofloxacin loaded sandbox oil based nanoemulsion and its potential for transdermal drug delivery

Abstract

The aim of this study is to develop a colloidal system for percutaneous delivery of drugs. Emulsification was achieved by mechano-chemical process and characterized by Cryo-TEM, FTIR and Zetasizer. Antimicrobial activities were measured using agar well diffusion method and skin corrosion study using Wistar rats. Significant difference in zone of inhibition (ZI) values of  Cp (ciprofloxacin), OF (ofloxacin), DOab+Cp (Cp-loaded sandbox oil based emulsion) and DOab+OF (OF-loaded sandbox oil based emulsion) was noted at p < 0.05 on both the standard and isolate strains of S. aureus. The Minimum Inhibitory Concentration (MIC) of 15.07 µg/mL was recorded for both drug-loaded emulsions on the clinical isolates. Minimum Bactericidal Concentration (MBC) of 125 µg/mL was observed for both Cp and OF while MBC values of 62.50 µg/mL were noted for DOab+Cp and DOab+OF. Cryo-TEM micrographs showed spherical morphology of the emulsions. The mean polydispersity index (PDI)/charge of 0.78/-7.03±0.008, 0.279/-8.96±0.007, and 0.380/- 12.4±0.136 mV were recorded for DOab, DOab+Cp and DOab+OF with droplet sizes of 291.20, 229.0, and 226.30 nm, respectively. The FTIR shows no drug-excipient interaction with prominent peaks at 3570-3200 cm-1 for OH and 3050-2895 cm-1 for CH3 and CH2. An effective voltage charge/conductivity values of 146.6/0.136, 147.1/0.427 and 147.1 mScm-1/0.383 V were recorded for DOab, DOab+Cp, and DOab+OF, respectively. 14 days of corrosion evaluation study recorded zero for skin damage. Drug absorption study values of 0.738 and 0.8877 µg/mL were noted in the skin and plasma for DOab+Cp, 0.9671 and 0.5176 µg/mL were recorded in skin and plasma for DOab+OF.  The outcome of this study shows that the emulsion improved the therapeutic value of the drugs and posed no threat to delicate tissues of the skin.Keywords:Enzymatic-degradation; Nanoemulsion; Encapsulation;Transdermopharmaceutical; Morphological