Cobalt Oxide-Infused Ofloxacin Nanocarriers: A Strategy to Overcome MDR Acinetobacter Baumannii Infections
Abstract
Multidrug resistant (MDR) Acinetobacter baumannii represents a critical healthcare challenge due to its ability to evade conventional antibiotics. In this work, we report the fabrication of ofloxacin loaded nanotherapeutics enhanced with cobalt oxide (CoO) metallic ions (Co²⁺) as a dual mechanism antibacterial agent against MDR A. baumannii. The nanotherapeutic system was prepared via a one pot co precipitation/adsorption method, yielding CoO–ofloxacin nanoparticles (CoO OFX NPs). Comprehensive physicochemical characterization showed: average particle size of 85 ± 10 nm (by dynamic light scattering, DLS), zeta potential of + 28.3 mV (indicating colloidal stability), a CoO incorporation of ~12.6 wt % (by inductively coupled plasma optical emission spectroscopy, ICP OES), and drug loading efficiency of ofloxacin at 68.1 % with a drug loading capacity of 132 µg/mg NP. Crystallinity was confirmed by X ray diffraction (XRD) showing peaks consistent with CoO (face centred cubic) and a slight broadening indicative of nanoscale dimensions; Fourier transform infrared spectroscopy (FTIR) revealed characteristic bands of ofloxacin and cobalt–oxygen interactions; transmission electron microscopy (TEM) images displayed spherical particles with a core–shell morphology (CoO core ~50 nm, ofloxacin shell ~15 nm). The in vitro release profile exhibited a sustained release of ofloxacin: ~35 % within 4 h, ~62 % at 24 h, and ~88 % at 72 h in phosphate buffered saline (pH 7.4, 37 °C). Antibacterial testing against a clinical MDR A. baumannii strain showed a minimum inhibitory concentration (MIC) of the CoO OFX NPs at 0.25 µg/mL (ofloxacin equivalent), compared to 2.0 µg/mL for free ofloxacin. A time kill assay demonstrated complete (>99.9 %) bacterial eradication within 6 h at 1× MIC of CoO OFX NPs, whereas free ofloxacin required 24 h at 4× MIC.
How to Cite
Madhu Bala, "Cobalt Oxide-Infused Ofloxacin Nanocarriers: A Strategy to Overcome MDR Acinetobacter Baumannii Infections", Vol. 3, Issue 4, 07-07-2025, pp. 50-56.
