Title : Experimental design of ciprofloxacin HCl-loaded nanoparticle formulation for an enhanced antimicrobial activity
Ciprofloxacin HCL is a second generation fluoroqinolone antibiotic, the most commonly used for the treatment of various infectious diseases like urinary tract infections against a wide range of Gram-positive and Gram-negative bacteria. However, many studies revealed that ciprofloxacin HCl has some disadvantages because of their poor intracellular accumulation and increasing resistance rate. Ciprofloxacin HCl entrapped nano-drug delivery systems may overcome these problems by decreasing the efflux of the antibiotic and increasing the antibiotic concentration on the target side.
The aim of this study was to develop and optimize ciprofloxacin HCl-loaded bovine serum albumin (BSA) nanoparticles utilizing full factorial design and to investigate the antimicrobial activity of the optimized formulation against urinary tract infections. Ciprofloxacin HCl-loaded BSA nanoparticles were fabricated using desolvation method and optimized utilizing 23 full factorial design (Design Expert 7.0 software). BSA concentration (%) (X1) and pH of aqueous BSA solution (X2) were selected as independent variables while particle size (nm) (Y1), zeta potential (mV) (Y2) and encapsulation efficiency (%) (Y3) were selected as dependent variables. During the optimization studies the formulation prepared at pH 8.60 by using 2% BSA concentration was determined as optimum formulation. The properties of the optimized ciprofloxacin HCl-loaded BSA nanoparticles predicted by the 23 factorial design approach correlated very well with the experimental determined particle size of 238.2 nm, zeta potential of -27,6 mV and encapsulation efficiency of 38.11%. The antimicrobial activity of the optimized formulation and unloaded nanoparticles was determined using conventional agar diffusion method against Escherichia coli ATCC 25922, Enterococcus faecalis ATCC 29212, Staphylococcus aureus ATCC 29213 and Pseudomonas aeruginosa ATCC 27853, as a zone of inhibition and results were evaluated according to European Committee on Antimicrobial Susceptibility Testing standards. In addition, the minimal inhibition concentration of the optimum formulation was evaluated by broth microdilution method. The antimicrobial activity studies demonstrated that the optimized ciprofloxacin HCl-loaded albumin nanoparticle formulation had an enhanced antimicrobial activity against the bacteria.