Formulation of biodegradable alginate-based nano-carriers for in-vitro drug delivery and antibacterial activity

Evaluation of the controlled release of ciprofloxacin (CIP.HCl) and the antibacterial efficacy of alginate (ALG)-based nanocarriers constitute the primary objectives of the current work. Herein, ALG-based nano-structures were prepared by the co-precipitation method and thoroughly analyzed using different characterization techniques, i.e., fourier transform infrared (FT-IR), powder X-ray diffraction (PXRD), scanning electron microscopy (SEM) and zeta potential (ZP). The intense peaks emerged at 500, 545, and 750 cm^-1 due to the CeO bond. Peaks that appeared at 550-600 cm^-1 and 525 cm^-1 are due to the stretching vibrations of FeO and ZnO bonds, respectively. Lowering of the peaks from 1640 to 1630 cm^-1 and 1420 to 1384 cm^-1 were observed in ALG-based nanocomposite (NC) due to the interaction of ALG with metal oxides (MO), which confirmed the formulation of CeO₂/ZnFe₂O₄/ALG nanocomposite. The diffraction peaks at 28.6^°, 56.6^°, 76.5^°, 37^°, 47.9^°, 62.3^°, 74^°, 13^°, 21^° confirmed the synthesis of MO (crystallite size 15.74 nm) and CeO₂/ZnFe₂O₄/ALG (12 nm). In accordance with morphological studies, CeO₂/ZnFe₂O₄ oxides had a uniform distribution throughout the relatively smooth and permeable surface of the ALG-based NC. Ciprofloxacin (CIP) was used as a model drug. Negative values of ZP revealed that CIP-loaded nanocomposite (CeO₂/ZnFe₂O₄/ALG/CIP) had more stability than CeO₂/ZnFe₂O₄/ALG. The maximum percentage of loading around 25 % on ALG NC was examined using the optical density (OD) method at pH 5.5. Correlation coefficients from the first order (0.971), Korsmeyer (0.9858), and Hixson (0.9021) models show the best-fitted models of the release profile in all circumstances. The release mechanism was investigated using various kinetics models. The controlled drug released was observed around 17 % at 40 °C after 3 h at pH 7.4, which is almost identical to the body temperature of a human, which is 37 °C. Similarly, after 24 h, sustained and controlled in-vitro release of the drug was studied, and it was 37, 72, and 74 % at pH 2.2, 7.4, and 9.4, respectively. Thus, prepared ALG-based NC is suitable for the controlled in-vitro release of (CIP.HCl). Metal oxides (CeO₂/ZnFe₂O₄) and ALG-based nanocomposite (CeO₂/ZnFe₂O₄/ALG) showed great antibacterial activity against Staphylococcus aureus (S. aureus) like 15 mm and 14 mm than Escherichia coli (E. coli).