Engineered mixed oxide-based polymeric composites for enhanced antimicrobial activity and sustained release of...

Here, pH-responsive engineered polymeric composites were fabricated from sodium alginate and mixed Cu/Zn oxides. The resulting alginate-Cu_xZn_1-xO composites were characterized by FTIR, SEM and XRD, then used as an efficient carrier for the antiretroviral drug (zidovudine, AZT) and exhibited remarkable antibacterial properties. The resulting polymeric composites had specific surface areas of 185.2-198.6 m²/g as confirmed by the Brunauer-Emmett-Teller analysis. The metal oxide distribution within the alginate matrix was confirmed from the X-ray diffraction and scanning electron microscopy analyses. The zidovudine, an antiretroviral drug was encapsulated in 30 mg of alginate-Cu_0.7Zn_0.3O with 68% encapsulation efficiency. The release of AZT in simulated intestinal fluid (pH 7.4) was studied, a slow and sustained release of AZT (~96.2%) was observed. The AZT release kinetics is sufficiently described by the Korsmeyer-Peppas model and follows the Fickian transport profile. Results herein demonstrated that A-Cu_0.7Zn_0.3O, A-Cu_0.3Zn_0.7O and Cu_0.5Zn_0.5O exhibited excellent bacterial devastation property. A dose of 8 μg/mL A-Cu_0.7Zn_0.3O and 13 μg/mL A-Cu_0.3Zn_0.7O are sufficient to completely killed E. coli DH5a and S. aureus NSUHS-151 within 24 h.